| 单词 | multicellular |
| 例句 | All across Yazd, people faced the qibla to pray, a titanic multicellular entity focused on the same moment in space-time. Darius the Great Is Not Okay 2018-08-28T00:00:00Z With this, we were off to an explosive developmental stage in which great varieties of respiring life, including the multicellular forms, became feasible. The Lives of a Cell 1974-01-01T00:00:00Z Eventually the dimming will reverse itself, but scientists predict all multicellular life on Earth will perish long before that occurs. We Are the Ants 2016-01-19T00:00:00Z These formed single-celled life, which, he says, inevitably led to multicellular life, and eventually all animals and plants. Ask a grown-up: what is the answer to life, the universe and everything? 2012-11-09T23:00:38Z At a mere 0.14mm in length they are also the smallest multicellular animals. New to Nature No 88: Euryplatea nanaknihali 2012-10-13T23:05:52Z As such, it has been around since the origins of multicellular life. How microbes in food can impact your body’s defenses against cancer 2023-02-28T05:00:00Z For multicellular cooperation to work, cells must engage in behaviors that serve the collective. How microbes in food can impact your body’s defenses against cancer 2023-02-28T05:00:00Z Every human body is a symphony of multicellular cooperation. How microbes in food can impact your body’s defenses against cancer 2023-02-28T05:00:00Z Thirty trillion cells cooperate and coordinate with each other to make us viable multicellular organisms. How microbes in food can impact your body’s defenses against cancer 2023-02-28T05:00:00Z "The bias against one division we observed in Chlamydomonas was very likely present in direct ancestors of its multicellular relatives and was further amplified as they evolved greater size and complexity," speculates Umen. New discovery on how green algae count cell divisions illuminates key step needed for the evolution of multicellular life 2023-11-13T05:00:00Z Environmental conditions were unsuitable for large multicellular organisms due to low oxygen levels. Our Evolutionary Past Can Teach Us about AI’s Future 2023-11-07T05:00:00Z Mishina believes that as we find more examples of horizontal gene transfer between multicellular organisms, we will gain insight into this phenomenon as well as evolution in general. Stolen genes allow parasitic control of behavior 2023-10-19T04:00:00Z This makes a quarter of a billion years simply too far into the future to forecast fates for mammals—or most any other kind of multicellular life, for that matter. Will the Next Supercontinent Really Drive Mammals to Extinction? 2023-10-17T04:00:00Z Most are microscopic, single-celled organisms like amoebas, algae, and diatoms, but larger multicellular protists exist -- such as kelp, slime moulds, and red algae. The end of genes: Routine test reveals unique divergence in genetic code 2023-10-05T04:00:00Z This unexpected bias against a single division has important implications for understanding the evolution of multicellular life and provides a new avenue for engineering algal cells for improved yields of biofuel and high value products. New discovery on how green algae count cell divisions illuminates key step needed for the evolution of multicellular life 2023-11-13T05:00:00Z The evolution of multicellularity led to the Cambrian explosion, a period more than 500 million years ago when large multicellular animals appeared in great diversity. Our Evolutionary Past Can Teach Us about AI’s Future 2023-11-07T05:00:00Z In the early embryonic development of multicellular organisms, gastrulation plays a key role. Did animal evolution begin with a predatory lifestyle? 2023-09-29T04:00:00Z C. elegans was the first multicellular organism to have its entire genome and nervous system mapped. Worm Brains, Decoded like Never Before, Could Shed Light on Our Own Mind 2023-08-21T04:00:00Z The lungs of patients who died from severe COVID-19 are often riddled with large, multicellular structures called syncytia, which scientists believe may contribute to the respiratory symptoms of the disease. Could fused neurons explain COVID-19’s ‘brain fog’? 2023-06-06T04:00:00Z This enables a single cell to rapidly produce a whole new multicellular individual with hundreds or even thousands of cells, an ability that is critical for fitness and survival. New discovery on how green algae count cell divisions illuminates key step needed for the evolution of multicellular life 2023-11-13T05:00:00Z If it’s behind us, then it may have occurred when life spontaneously emerged, for example, or when single-cell organisms transitioned to multicellular ones. Most Aliens May Be Artificial Intelligence, Not Life as We Know It 2023-06-01T04:00:00Z To understand—and perhaps ultimately to control—the forms of multicellular structures, we need to figure out these behavioral rules. Synthetic Morphology Lets Scientists Create New Life-Forms 2023-05-31T04:00:00Z It focuses specifically on benthic metazoans — multicellular animals living at the bottom of the ocean. Thousands of New Creatures Discovered in Deep-Sea Mining Zone 2023-05-26T04:00:00Z Members of this subgroup range in size from single-celled diatoms to the massive and multicellular kelp. Fundamentals of Biology 2015-01-01T00:00:00Z In most multicellular organisms, cells combine to make tissues, which are groups of similar cells carrying out the same function. Concepts of Biology 2013-04-25T00:00:00Z With their multicellular bodies, animals evolved into a staggering range of forms, like whales that weigh 200 tons, birds that soar six miles into the sky and sidewinders that slither across desert dunes. Bizarre Sea Creatures Illuminate the Dawn of the Animal Kingdom 2023-05-17T04:00:00Z An even more striking example of this apparent “overall vision” of multicellular structures is found in primitive flatworms called planarians. Synthetic Morphology Lets Scientists Create New Life-Forms 2023-05-31T04:00:00Z These strange snowflakes are at the heart of experiments exploring what might have happened millions of years ago when single-celled creatures first banded together to become multicellular. An Experiment Repeated 3,000 Times Finds Hints to Evolution’s Secrets 2023-05-10T04:00:00Z The brown algae are primarily marine, multicellular organisms that are known colloquially as seaweeds. Fundamentals of Biology 2015-01-01T00:00:00Z When the haploid spore germinates, it generates a multicellular gametophyte by mitosis. Concepts of Biology 2013-04-25T00:00:00Z A quick refresher from your sex-ed class: Normally, an embryo — in everything from humans down to the simplest multicellular animal — develops after a sperm fertilizes an egg. Scientists discover bizarre type of sex in this ‘crazy’ ant 2023-04-06T04:00:00Z Over a couple of days the cells clumped into little clusters that began behaving like multicellular microorganisms, sprouting cilia, hairlike protrusions that beat in a synchronized way to propel the clusters through the fluid. Synthetic Morphology Lets Scientists Create New Life-Forms 2023-05-31T04:00:00Z The finding suggests that feeding all the cells in a cluster is a crucial part of the trade-offs an organism faces as it goes multicellular. An Experiment Repeated 3,000 Times Finds Hints to Evolution’s Secrets 2023-05-10T04:00:00Z However, the individual sperm and egg themselves never become multicellular beings. Fundamentals of Biology 2015-01-01T00:00:00Z Animals are complex multicellular organisms that require a mechanism for transporting nutrients throughout their bodies and removing wastes. Concepts of Biology 2013-04-25T00:00:00Z Seaweed and fossils of some other multicellular organisms were identified in the black shale. Study explains how primordial life survived on 'Snowball Earth' 2023-04-04T04:00:00Z Some of the earliest work on multicellular synthetic biology also used bacteria. Synthetic Morphology Lets Scientists Create New Life-Forms 2023-05-31T04:00:00Z The first two have evolved in sync over the past 3.7 billion years and resulted in every surviving multicellular species alive today. Opinion | Weakening the public health system is a recipe for disaster 2023-03-13T04:00:00Z Most plants exhibit alternation of generations, which is described as haplodiplodontic: the haploid multicellular form, known as a gametophyte, is followed in the development sequence by a multicellular diploid organism: the sporophyte. Fundamentals of Biology 2015-01-01T00:00:00Z Figure 7.1 Each of us, like these other large multicellular organisms, begins life as a fertilized egg. Concepts of Biology 2013-04-25T00:00:00Z The findings support the idea that it was more of a "Slushball Earth" where the earliest forms of complex life - basic multicellular organisms - endured even at mid-latitudes previously thought to have been frozen solid. Study explains how primordial life survived on 'Snowball Earth' 2023-04-04T04:00:00Z Another demonstration of the versatility of cells in multicellular structures is provided by so-called chimeric embryos, which contain cells from more than one type of organism. Synthetic Morphology Lets Scientists Create New Life-Forms 2023-05-31T04:00:00Z Scientists have sequenced and studied thousands of human and microbial genomes, but the complete deciphering of the DNA of other multicellular organisms has lagged. Eleven science stories likely to make big news in 2023 2023-01-04T05:00:00Z Some green algae are single cells, such as Chlorella and Chlamydomonas, which adds to the ambiguity of green algae classification, because plants are multicellular. Fundamentals of Biology 2015-01-01T00:00:00Z While many single-celled organisms and a few multicellular organisms can produce genetically identical clones of themselves through mitotic cell division, many single-celled organisms and most multicellular organisms reproduce regularly using another method. Concepts of Biology 2013-04-25T00:00:00Z The appearance of multicellular organisms was a key evolutionary advance for life on Earth. Odd cave bacterium forms a multicellular ‘body,’ like plants and animals 2022-10-18T04:00:00Z Microbes are known to swap genes all the time, helping them adapt to new conditions, but multicellular organisms seemed to borrow genes only rarely. Genes for seeds arose early in plant evolution, ferns reveal 2022-09-22T04:00:00Z Success in the lab would pave the way for genetic engineering not yet possible in most multicellular bioluminescent organisms, Hensley says. How the sea fireflies of the Caribbean are shining new light on evolution 2022-08-24T04:00:00Z In the multicellular Ulva, a sporophyte grows by mitosis after fertilization. Fundamentals of Biology 2015-01-01T00:00:00Z In multicellular organisms, the new diploid cell will then undergo mitotic cell divisions to develop into an adult organism. Concepts of Biology 2013-04-25T00:00:00Z Plants and animals are the textbook examples of multicellular life, but some microbes, too, exhibit a few simple aspects of group behavior. Odd cave bacterium forms a multicellular ‘body,’ like plants and animals 2022-10-18T04:00:00Z In multicellular organisms, cells send and receive chemical messages constantly to coordinate the actions of distant organs, tissues, and cells. Biology for AP Courses 2022-06-09T00:00:00Z In fact, sneezing doesn’t even require a nervous system, let alone a nose, and dates back to some of the first multicellular animals: sponges. Sneeze by Sneeze, Sponges Fill the Seas With Their Mucus 2022-08-10T04:00:00Z Additionally, mosses are anchored to the substrate—whether it is soil, rock, or roof tiles—by multicellular rhizoids. Fundamentals of Biology 2015-01-01T00:00:00Z Most fungi and algae employ a life-cycle strategy in which the multicellular “body” of the organism is haploid. Concepts of Biology 2013-04-25T00:00:00Z In her mind, the cells of a true multicellular organism can only survive and reproduce as part of a larger organism—which isn’t the case for HS-3. Odd cave bacterium forms a multicellular ‘body,’ like plants and animals 2022-10-18T04:00:00Z The ability of cells to communicate through chemical signals originated in single cells and was essential for the evolution of multicellular organisms. Biology for AP Courses 2022-06-09T00:00:00Z Others form multicellular organisms—plants, animals, and fungi. Miller & Levine Biology 2018-01-01T00:00:00Z All animals are eukaryotic, multicellular organisms, and almost all animals have a complex tissue structure with differentiated and specialized tissues. Fundamentals of Biology 2015-01-01T00:00:00Z The haploid multicellular plants are called gametophytes because they produce gametes. Concepts of Biology 2013-04-25T00:00:00Z And she and others stress that multicellular larger organisms must be sensitive to natural selection. Odd cave bacterium forms a multicellular ‘body,’ like plants and animals 2022-10-18T04:00:00Z Why is signaling in multicellular organisms more complicated than signaling in single-celled organisms? Biology for AP Courses 2022-06-09T00:00:00Z In multicellular organisms, cells are specialized and usually work together to perform specific tasks. Miller & Levine Biology 2018-01-01T00:00:00Z Germination of the spores results in the formation of a multicellular mycelium. Fundamentals of Biology 2015-01-01T00:00:00Z Most protists are microscopic and unicellular, but some true multicellular forms exist. Concepts of Biology 2013-04-25T00:00:00Z Thus, to her, “The cave bacterium is another example for a prokaryote with a transient multicellular stage.” Odd cave bacterium forms a multicellular ‘body,’ like plants and animals 2022-10-18T04:00:00Z Even though all cells of a multicellular organism have the same set of genes, the set of proteins produced in different tissues is different and dependent on gene expression. Biology for AP Courses 2022-06-09T00:00:00Z The cells of humans and other multicellular organisms do not live on their own. Miller & Levine Biology 2018-01-01T00:00:00Z Conidiospores are unicellular or multicellular spores that are released directly from the tip or side of the hypha. Fundamentals of Biology 2015-01-01T00:00:00Z These species have both haploid and diploid multicellular organisms as part of their life cycle. Concepts of Biology 2013-04-25T00:00:00Z Organisms containing more than one cell are said to be multicellular. Environmental Biology 2018-09-06T00:00:00Z Figure 19.1 Living things may be single-celled or complex, multicellular organisms. Biology for AP Courses 2022-06-09T00:00:00Z The cells of multicellular organisms are specialized for specific tasks and communicate with one another to maintain homeostasis. Miller & Levine Biology 2018-01-01T00:00:00Z The haploid gametophyte produces the male and female gametes by mitosis in distinct multicellular structures. Fundamentals of Biology 2015-01-01T00:00:00Z Even though all cells in a multicellular organism have the same set of genes, the set of proteins produced in different tissues is different and dependent on gene expression. Concepts of Biology 2013-04-25T00:00:00Z Unlike the other domains, Domain Eukarya contains multicellular organisms, in addition to unicellular species. Environmental Biology 2018-09-06T00:00:00Z The solution to producing larger organisms is for them to become multicellular. Biology for AP Courses 2022-06-09T00:00:00Z A lichen is a symbiotic association between a multicellular fungus, a yeast, and a photosynthetic organism. Miller & Levine Biology 2018-01-01T00:00:00Z One of the megaspores divides to form the multicellular female gametophyte, while the others divide to form the rest of the structure. Fundamentals of Biology 2015-01-01T00:00:00Z Whether in a simple unicellular organism or in a complex multicellular organism, each cell controls when and how its genes are expressed. Concepts of Biology 2013-04-25T00:00:00Z Kingdom Fungi includes multicellular and unicellular, heterotrophic fungi. Environmental Biology 2018-09-06T00:00:00Z Every cell of the multicellular offspring has copies of the original two sets of homologous chromosomes. Biology for AP Courses 2022-06-09T00:00:00Z Ancestors of land plants lived in water, like green algae, and most were unicellular, though some were multicellular. Miller & Levine Biology 2018-01-01T00:00:00Z In most multicellular organisms, cells combine to make tissues, which are groups of similar cells carrying out similar or related functions. Fundamentals of Biology 2015-01-01T00:00:00Z Cells in multicellular organisms are specialized; cells in different tissues look very different and perform different functions. Concepts of Biology 2013-04-25T00:00:00Z As a group, protists are very diverse and include unicellular, multicellular, heterotrophic, and autotrophic organisms. Environmental Biology 2018-09-06T00:00:00Z Haploid dominant life cycles have a multicellular haploid stage, as in fungi. Biology for AP Courses 2022-06-09T00:00:00Z Animals are multicellular, heterotrophic, eukaryotic organisms with cells that lack cell walls. Miller & Levine Biology 2018-01-01T00:00:00Z Most fungi produce a large number of spores, which are haploid cells that can undergo mitosis to form multicellular, haploid individuals. Fundamentals of Biology 2015-01-01T00:00:00Z Another feature that makes studying the mitochondrial genome interesting is that in most multicellular organisms, the mitochondrial DNA is passed on from the mother during the process of fertilization. Concepts of Biology 2013-04-25T00:00:00Z UV-B cannot penetrate multicellular organisms very far and thus tends to only affect cells near the surface, such as in the skin of animals. Environmental Biology 2018-09-06T00:00:00Z In a diploid dominant cycle, a multicellular haploid stage is present, as in humans. Biology for AP Courses 2022-06-09T00:00:00Z Cloned colonies of bacteria and other microorganisms are easy to grow, but this is not always true of multicellular organisms, especially animals. Miller & Levine Biology 2018-01-01T00:00:00Z Dimorphic fungi can change from the unicellular to multicellular state depending on environmental conditions. Fundamentals of Biology 2015-01-01T00:00:00Z The ancestors of today’s multicellular eukaryotes are thought to have evolved about 1.5 billion years ago. Concepts of Biology 2013-04-25T00:00:00Z DNA is the genetic material found in all organisms, ranging from single-celled bacteria to multicellular mammals. Environmental Biology 2018-09-06T00:00:00Z In a haploid dominant life cycle, a multicellular diploid stage is present, as in fungi. Biology for AP Courses 2022-06-09T00:00:00Z All multicellular animals are placed in the kingdom Animalia. Miller & Levine Biology 2018-01-01T00:00:00Z Other protists have multicellular stages in both haploid and diploid forms, a strategy called alternation of generations that is also used by plants. Fundamentals of Biology 2015-01-01T00:00:00Z Not all protists are microscopic and single-celled; there exist some very large multicellular species, such as the kelps. Concepts of Biology 2013-04-25T00:00:00Z Kingdom Animalia is comprised of multicellular, heterotrophic organisms. Environmental Biology 2018-09-06T00:00:00Z In a haploid dominant life cycle, a multicellular haploid stage is present, as in plants. Biology for AP Courses 2022-06-09T00:00:00Z Members of the kingdom Animalia are multicellular and heterotrophic, and lack cell walls. Miller & Levine Biology 2018-01-01T00:00:00Z When the haploid spore germinates in a hospitable environment, it generates a multicellular gametophyte by mitosis. Fundamentals of Biology 2015-01-01T00:00:00Z A few protists live as colonies that behave in some ways as a group of free-living cells and in other ways as a multicellular organism. Concepts of Biology 2013-04-25T00:00:00Z In multicellular organisms, such as animals, molecules can interact to form cells that combine to form tissues, which make up organs. Environmental Biology 2018-09-06T00:00:00Z After all, prokaryotes are but single cells exposed directly to their environment, whereas the sex cells of multicellular organisms are usually sequestered in protected parts of the body. Biology for AP Courses 2022-06-09T00:00:00Z No multicellular organism by itself can break down the cellulose molecules found in leaves. Miller & Levine Biology 2018-01-01T00:00:00Z Like other multicellular organisms, plants grow through a combination of cell growth and cell division. Fundamentals of Biology 2015-01-01T00:00:00Z Most plants exhibit alternation of generations, which is described as haplodiplontic: the haploid multicellular form known as a gametophyte is followed in the development sequence by a multicellular diploid organism, the sporophyte. Concepts of Biology 2013-04-25T00:00:00Z These combinations continue until entire multicellular organisms are formed. Environmental Biology 2018-09-06T00:00:00Z It follows from this idea that the gene transfers between multicellular eukaryotes should be more difficult. Biology for AP Courses 2022-06-09T00:00:00Z Gene regulation in eukaryotes is more complex than in prokaryotes because of the way in which genes are expressed in a multicellular organism. Miller & Levine Biology 2018-01-01T00:00:00Z Like other multicellular organisms, plants grow through a combination of cell growth and cell division. Fundamentals of Biology 2015-01-01T00:00:00Z Only a single surviving haploid cell will develop into a female multicellular gametophyte that encloses an egg. Concepts of Biology 2013-04-25T00:00:00Z This eon marks the proliferation of multicellular animals with hard body parts, such as shells, which are preserved in the geological record as fossils. An Introduction to Geology 2017-01-01T00:00:00Z Prokaryotes have been on Earth since long before multicellular life appeared. Biology for AP Courses 2022-06-09T00:00:00Z Cell differentiation requires genetic specialization, yet most of the cells in a multicellular organism carry the same DNA in their nucleus. Miller & Levine Biology 2018-01-01T00:00:00Z Both the gametophyte and sporophyte stages are multicellular. Fundamentals of Biology 2015-01-01T00:00:00Z In fact, approximately one-quarter of the world’s photosynthesis is conducted by protists, particularly dinoflagellates, diatoms, and multicellular algae. Concepts of Biology 2013-04-25T00:00:00Z For example, multicellular protists, ancient eukaryotes, do not have cells organized into tissues. Anatomy and Physiology 2013-06-19T00:00:00Z The tissues of multicellular, complex animals are four primary types: epithelial, connective, muscle, and nervous. Biology for AP Courses 2022-06-09T00:00:00Z Research shows the first animals evolved from ancestors shared with living choanoflagellates, with the oldest evidence of multicellular life coming from 600-million-year-old microscopic fossils. Miller & Levine Biology 2018-01-01T00:00:00Z The red and green algae include unicellular, multicellular, and colonial forms. Fundamentals of Biology 2015-01-01T00:00:00Z The sporangium, the multicellular sexual reproductive structure, is present in bryophytes. Concepts of Biology 2013-04-25T00:00:00Z The multicellular exocrine glands known as serous glands develop from simple epithelium to form a secretory surface that secretes directly into an inner cavity. Anatomy and Physiology 2013-06-19T00:00:00Z Even the simplest multicellular eukaryotes like sponges and cnidarians have developed cells that specialize in immune defenses to protect against disruptions to homeostasis. Biology for AP Courses 2022-06-09T00:00:00Z Each specialized cell in a multicellular organism contributes to homeostasis in the organism. Miller & Levine Biology 2018-01-01T00:00:00Z Some protists are unicellular in the haploid form and multicellular in the diploid form, a strategy employed by animals. Fundamentals of Biology 2015-01-01T00:00:00Z All multicellular organisms use cell division for growth, and in most cases, the maintenance and repair of cells and tissues. Concepts of Biology 2013-04-25T00:00:00Z Other multicellular exocrine glands release their contents through a tubular duct. Anatomy and Physiology 2013-06-19T00:00:00Z Cell-surface receptors are involved in most of the signaling in multicellular organisms. Biology for AP Courses 2022-06-09T00:00:00Z In a multicellular organism, specialized cells are organized into tissues. Miller & Levine Biology 2018-01-01T00:00:00Z The sporangium—the multicellular sexual reproductive structure—is present in bryophytes and absent in the majority of algae. Fundamentals of Biology 2015-01-01T00:00:00Z The first genomes to be sequenced, such as those belonging to viruses, bacteria, and yeast, were smaller in terms of the number of nucleotides than the genomes of multicellular organisms. Concepts of Biology 2013-04-25T00:00:00Z In multicellular organisms, including humans, all cells, tissues, organs, and organ systems of the body work together to maintain the life and health of the organism. Anatomy and Physiology 2013-06-19T00:00:00Z Trillions of cell divisions subsequently occur in a controlled manner to produce a complex, multicellular human. Biology for AP Courses 2022-06-09T00:00:00Z Cell growth and cell division are highly controlled in multicellular organisms. Miller & Levine Biology 2018-01-01T00:00:00Z Putting the studies together, Gibbons concludes the genomes of “domesticated prokaryotes and microbial eukaryotes are very similar” to each other and to multicellular domesticated organisms. Humans tamed the microbes behind cheese, soy, and more 2022-06-28T04:00:00Z Some fungi are dimorphic because they can go from being unicellular to multicellular depending on environmental conditions. Concepts of Biology 2013-04-25T00:00:00Z All living cells in multicellular organisms contain an internal cytoplasmic compartment, and a nucleus within the cytoplasm. Anatomy and Physiology 2013-06-19T00:00:00Z All multicellular organisms use cell division for growth, maintenance, and repair of tissues. Biology for AP Courses 2022-06-09T00:00:00Z In multicellular organisms, cells must be differentiated and specialized. Miller & Levine Biology 2018-01-01T00:00:00Z Until now, the packing of a cell’s DNA inside a membrane-bound nucleus, like the seed of an avocado, was thought to be strictly limited to cells of more complex, multicellular organisms. Scientists baffled by discovery of bacteria that ought to be too big to function 2022-06-23T04:00:00Z All animals are eukaryotic, multicellular organisms, and almost all animals have specialized tissues. Concepts of Biology 2013-04-25T00:00:00Z Despite differences in structure and function, all living cells in multicellular organisms have a surrounding cell membrane. Anatomy and Physiology 2013-06-19T00:00:00Z How does this regulatory outcome benefit a multicellular organism? Biology for AP Courses 2022-06-09T00:00:00Z Gene regulation also allows multicellular organisms to reproduce. Miller & Levine Biology 2018-01-01T00:00:00Z We humans are multicellular organisms, our bodies made up of about 30 trillion cells. You Don’t Need a Microscope to See the Biggest Bacteria Ever Found 2022-06-23T04:00:00Z As multicellular organisms, most animals develop specialized cells that group together into tissues with specialized functions. Concepts of Biology 2013-04-25T00:00:00Z And for almost all species of multicellular animals, procreation requires that sperm meets egg. A microscopic arms race is happening between sperm 2022-06-19T04:00:00Z Many unicellular organisms, such as yeast, and a few multicellular organisms, such as sponges, can produce genetically identical clones of themselves through cell division. Biology for AP Courses 2022-06-09T00:00:00Z Some homologous Hox genes are found in almost all multicellular animals, from fruit flies to humans. Miller & Levine Biology 2018-01-01T00:00:00Z They span 15 phyla, ranging from microscopic, barely multicellular blobs to 130-foot-long tapeworms snuggly coiled inside whale guts—species as phylogenetically different from one another as humans are from insects and jellyfish. The Scientists Fighting for Parasite Conservation 2022-05-18T04:00:00Z The multicellular bodies of animals consist of tissues that make up more complex organs and organ systems. Concepts of Biology 2013-04-25T00:00:00Z Still, she puts her all into creating that multicellular burrow in the ground. Why you should plant a garden that’s wasp-friendly 2022-04-19T04:00:00Z However, many single-celled organisms and most multicellular organisms reproduce regularly using a method requiring two parents. Biology for AP Courses 2022-06-09T00:00:00Z Many green algae form colonies, and they provide a hint about how the first multicellular plants may have evolved. Miller & Levine Biology 2018-01-01T00:00:00Z Previous research indicated branching networks of hyphae, of which multicellular fungi called mycelia are composed, conduct electrical signals comparable to the neurons. It's not a bad trip: Mushrooms may be "talking" to each other, new study finds 2022-04-13T04:00:00Z The organ systems of an animal maintain homeostasis within the multicellular body. Concepts of Biology 2013-04-25T00:00:00Z Then, almost miraculously, over the course of just a few tens of millions of years, it regained its strength—just in time for the sudden profusion of complex multicellular life known as the Cambrian explosion. Scientists are probing the secrets of Earth’s inner core—and how it saved life on our planet 2022-03-30T04:00:00Z The spores develop into multicellular, haploid plants called gametophytes because they produce gametes. Biology for AP Courses 2022-06-09T00:00:00Z Researchers have long divided life into two groups: prokaryotes, which include bacteria and single-cell microbes called archaea, and eukaryotes, which include everything from yeast to most forms of multicellular life, including humans. Largest bacterium ever discovered has unexpectedly complex cells 2022-02-23T05:00:00Z Sponges have been around for at least 600 million years and were likely the first multicellular organisms on Earth. These sponges survive the deep sea by feeding on remains of long-dead animals 2022-02-08T05:00:00Z “That could indicate that by being a multicellular animal, you depend on having periods during which the tissues can repair and regenerate.” ‘If it’s alive, it sleeps.’ Brainless creatures shed light on why we slumber 2021-10-27T04:00:00Z Scientific evidence from astrobiology suggests that simple life — composed of individual cells, or small multicellular organisms — is ubiquitous in the universe. Analysis | Intelligent life probably exists on distant planets — even if we can’t make contact, astrophysicist says 2021-06-18T04:00:00Z Some organisms consist of a single cell and others are multicellular. Biology for AP Courses 2022-06-09T00:00:00Z No-one knows for sure, but a clue may reside in the staggering intricacy of gene expression that multicellular life had to master. It’s time to consign the “selfish gene” to the history books 2021-05-30T04:00:00Z In the past, they were successfully able to use the frog skin cells to shape little multicellular beings with the help of a complex computer algorithm. Frog stem cell research changes what we know about how organisms are built 2021-04-16T04:00:00Z Eventually, this led to multicellular organisms, animals, and us. The first organism to use oxygen may have appeared surprisingly early 2021-02-25T05:00:00Z This means that, among other things, scientists are not going to be looking for skeletons or the types of fossils associated with multicellular organisms like animal and plant life. If Perseverance finds life on Mars, this is what it will look like 2021-02-25T05:00:00Z Another feature that makes studying the mitochondrial genome interesting is that the mitochondrial DNA in most multicellular organisms is passed on from the mother during the process of fertilization. Biology for AP Courses 2022-06-09T00:00:00Z That set the stage for complex multicellular organisms, and eventually, humans to arise, Brunet and King suggest. Bizarre, bloblike motion of microscopic creature may give clues to early animal movement 2021-02-24T05:00:00Z The research also might shed new light on how multicellular organisms arose in the first place. Frog stem cell research changes what we know about how organisms are built 2021-04-16T04:00:00Z A slightly more sophisticated version of that experiment uses not cells but organoids — multicellular in vitro tissue with a structure that reflects the complexity of a full-scale organ. How much protein function needs to be restored in cystic fibrosis? 2020-07-28T04:00:00Z Corals — multicellular marine invertebrates belonging to the class Anthozoa of the phylum Cnidaria — usually live in compact colonies composed of individual structures called polyps. Model system might reveal how coral cells take up and evict algae 2020-06-16T04:00:00Z In a multicellular organism, different cell types will have different proteomes, and these will vary with changes in the environment. Biology for AP Courses 2022-06-09T00:00:00Z It’s unlikely that multicellular life would survive such irradiation, Lingam says. No star, no problem: Radioactivity could make otherwise frozen planets habitable 2020-04-01T04:00:00Z Although that might not seem so extraordinary from your privileged position in Kingdom Animalia, this multicellular microbe is not an animal. Marine Microbe Performs Animal Trick 2020-03-08T05:00:00Z Long before plants, fish, or dinosaurs, life at this time consisted of simple, multicellular organisms. The world’s oldest asteroid strike in Western Australia may have triggered a global thaw 2020-01-21T05:00:00Z This surprising finding that cell death supports the survival of senescent cells highlights the complexity of cell-death regulation in multicellular animals. Senescent cells feed on their neighbours 2019-10-27T04:00:00Z All living cells are bathed in liquid, whether they are in a single-celled organism or a multicellular one. Biology for AP Courses 2022-06-09T00:00:00Z Such changes in cGAS activity and cGAMP levels in response to viral infection also occur in a range of multicellular organisms, including humans. Bacterial twist to an antiviral defence 2019-10-07T04:00:00Z Microbes and larger multicellular organisms covered much of the seafloor in an organic mat similar to pond scum. Ancient, Pancake-Shaped Marine Animals Were on the Move 2019-09-27T04:00:00Z This period is known for the appearance of very early multicellular life forms. Early animal had 'complex behaviour' 2019-09-04T04:00:00Z Some argue the first multicellular organism was probably a sedentary filter feeder, like a microscopic sponge. The world’s first animal was probably a carnivore 2019-08-30T04:00:00Z It is hypothesized that phosphorylation of tyrosine residues is needed to control the more sophisticated functions of development, differentiation, and cellular communication used in multicellular organisms. Biology for AP Courses 2022-06-09T00:00:00Z "Tardigrades are ideal to include because they are microscopic, multicellular, and one of the most durable forms of life on planet Earth," Nova said. The indestructible 'water bears' stuck on the moon 2019-08-07T04:00:00Z In multicellular organisms, cells usually communicate with each other in a peaceful manner. Flower power as human cancer cells compete with normal cells 2019-07-23T04:00:00Z The regrowth of centuries-old mosses suggests that glaciers and permafrost are not merely graveyards for multicellular life, but they could instead help organisms withstand ice ages. Ancient life awakens amid thawing ice caps and permafrost 2019-07-05T04:00:00Z The first multicellular animal was probably a meat eater, the team reports this month in Evolution Letters. The world’s first animal was probably a carnivore 2019-08-30T04:00:00Z The four categories of signaling in multicellular organisms are paracrine signaling, endocrine signaling, autocrine signaling, and direct signaling across gap junctions. Biology for AP Courses 2022-06-09T00:00:00Z Ultimately, Extavour hopes that her mission to scrutinize the eggs, embryos and reproductive systems of insects will help her to understand the rules governing the evolution of the first multicellular organisms. The biologist overturning evolutionary doctrine 2019-07-02T04:00:00Z Tentative evidence for horizontal gene transfer emerged almost a century ago, but only in the past few decades have biologists recognized its influence on the evolution of multicellular organisms as well as Archaea and bacteria. Was Darwin Wrong? 2019-06-15T04:00:00Z These ice age zombies range from simple bacteria to multicellular animals, and their endurance is prompting scientists to revise their understanding of what it means to survive. Ancient life awakens amid thawing ice caps and permafrost 2019-07-05T04:00:00Z On 16 June, a team he leads will launch a $180 million global effort to identify more than 2 million new species of multicellular creatures. $180 million DNA 'barcode' project aims to discover 2 million new species 2019-06-06T04:00:00Z Figure 11.1 Each of us, like these other large multicellular organisms, begins life as a fertilized egg. Biology for AP Courses 2022-06-09T00:00:00Z Others range from unicellular eukaryotes to multicellular seaweeds many metres long. A brief history of slime 2019-06-02T04:00:00Z Our multicellular bodies and our genomes are full of parts that are remarkably cooperative because by cooperating they produce the most effective composite individual, and it’s the individual that reproduces. Be Careful with Occam’s Razor, You Might Cut Yourself 2019-05-19T04:00:00Z Just as different species compete for limited resources and space, so cells in a multicellular organism compete for a niche, and less-fit cells are eliminated to keep tissues and organs ‘youthful’. Elimination of unfit cells in young and ageing skin 2019-04-02T04:00:00Z The ranch contains about 60 species from the Ediacaran, the period when Earth’s first multicellular creatures arose some 560 million years ago. Top stories: The true cost of cash bail, tuft cells, and a fossil-saving Australian farmer 2019-03-29T04:00:00Z However, multicellular organisms that exclusively depend on asexual reproduction are exceedingly rare. Biology for AP Courses 2022-06-09T00:00:00Z Michael like some open-air diorama: the weird forms of Earth's first multicellular creatures, frozen in rock for 560 million years. This Australian farmer is saving fossils of some of the planet’s weirdest, most ancient creatures 2019-03-28T04:00:00Z These amoebozoans—a phylum of single-celled eukaryotes—spend most of their lives as individual organisms, but will gather into motile multicellular formations to search for food and reproduce. Did Crawling Critters Leave These Cracks? The Answer Could Rewrite Evolutionary History 2019-02-26T05:00:00Z Humans and all other multicellular eukaryotes, including plants, have specialized reproductive cells, such as sperm or eggs or their stem cells, and only bacterial genes picked up by those cells could be passed on. Plants and animals sometimes take genes from bacteria, study of algae suggests 2019-01-29T05:00:00Z And then there are fungi — perhaps the most mysterious kingdom of multicellular life. When Fungi Fight Back 2019-01-15T05:00:00Z Species with alternation of generations have both haploid and diploid multicellular organisms as part of their life cycle. Biology for AP Courses 2022-06-09T00:00:00Z There are even some fungi and multicellular organisms, like insects and worms, living deep below ground. Deep Beneath Your Feet, They Live in the Octillions 2018-12-19T05:00:00Z But the key to how multicellular ecosystems developed seems to lie in sandstones left by those chilly seas, in an ecosystem much more diverse than previously suspected. 600 Million Years Ago, the First Scavengers Lurked in Dark Ocean Gardens 2018-11-30T05:00:00Z Could it be used to track spatio-temporal changes in gene-expression profiles in multicellular systems and shed light on the development of animal and plant tissues and organs? CRISPR tool puts RNA on the record 2018-10-02T04:00:00Z Like animals, plants are eukaryotes — multicellular organisms — that split from a common ancestor called Luca billions of years ago. Watch Plants Light Up When They Get Attacked 2018-09-13T04:00:00Z The haploid multicellular plants are called gametophytes, because they produce gametes from specialized cells. Biology for AP Courses 2022-06-09T00:00:00Z Touched off by the initial transition from one cell to many, a cycle of increasing complexity took hold, and the richness of multicellular life today is the result. The momentous transition to multicellular life may not have been so hard after all 2018-06-28T04:00:00Z The few multicellular organisms grazed slowly on the congealed mats or sat atop them, using different body shapes to pluck nutrients from the currents. 600 Million Years Ago, the First Scavengers Lurked in Dark Ocean Gardens 2018-11-30T05:00:00Z It took 3 billion years for life to evolve from single to multicellular organisms. Review | A journey through billions of years that nails home the point: Life is a miracle 2018-06-22T04:00:00Z Back in the Proterozoic, a few million years after multicellular life appeared on the planet, the moon was about 211,825 miles away from Earth—about 21,000 miles closer than it is today. This Summer Solstice, Earth's Days Are Longer Than Ever 2018-06-20T04:00:00Z Compare the three main types of life cycles in multicellular organisms and give an example of an organism that employs each. Biology for AP Courses 2022-06-09T00:00:00Z A decade ago, a radical theory of cancer emerged: that this plague of multicellular organisms arises when their cells rewind the evolutionary clock and revert to acting like unicellular life. The momentous transition to multicellular life may not have been so hard after all 2018-06-28T04:00:00Z Nicol’s The Curious Life of Krill takes the reader deep into the Southern Ocean to look at the most abundant multicellular marine organism by weight. Sea changes: whales, krill and human exploitation 2018-06-12T04:00:00Z Ostracods have been around for almost 500 million years – not long after multicellular life first bloomed on Earth. When evolution’s path leads to a dead end 2018-06-08T04:00:00Z The creatures, made up of individual zooids - small, multicellular organisms - normally reside in warmer waters, like the tropics, and usually don’t travel farther north than the waters off southern California. Pyrosome population growing again off of Oregon coast 2018-04-22T04:00:00Z In a diploid dominant cycle, the multicellular diploid stage is present, as in humans. Biology for AP Courses 2022-06-09T00:00:00Z Cancers seem to "undo the molecular constraints and controls that evolved to enable multicellular life," Goode says. The momentous transition to multicellular life may not have been so hard after all 2018-06-28T04:00:00Z But Chitwood’s study showed that gene expression in the unicellular seaweed varies in ways that echo gene expression in similar structures in multicellular plants—suggesting that the dividing cell needn’t always dictate morphology. The Lost Art of Looking at Plants 2018-01-24T05:00:00Z But Chitwood’s study showed that gene expression in the unicellular seaweed varies in ways that echo gene expression in similar structures in multicellular plants — suggesting that the dividing cell needn’t always dictate morphology. The lost art of looking at plants 2018-01-22T05:00:00Z Two other types of microfossils had the same carbon ratios as microbes known as archaea that depend on methane as their energy source—and that played a pivotal role in the development of multicellular life. Life may have originated on Earth 4 billion years ago, study of controversial fossils suggests 2017-12-18T05:00:00Z In a diploid dominant cycle, a multicellular diploid stage is present, as in algae. Biology for AP Courses 2022-06-09T00:00:00Z Larger, multicellular organisms—with multiple flagella—were better at sweeping water past their cell membranes to harvest oxygen. The momentous transition to multicellular life may not have been so hard after all 2018-06-28T04:00:00Z Biologists study them to understand how unicellular organisms evolved to become the earliest multicellular animals. Bacterial 'aphrodisiac' sends single-celled organism into mating frenzy 2017-09-05T04:00:00Z Those creatures would be as small and unsatisfying to a complex multicellular organism as a flea would be to a tiger. The first animals evolved during the absolute worst time on Earth 2017-08-17T04:00:00Z I think what we all remember is simply that anything multicellular was able to survive at all. Are Tardigrades Really That Tough? 2017-07-23T04:00:00Z DNA is the genetic material found in all living organisms, ranging from single-celled bacteria to multicellular mammals. Biology for AP Courses 2022-06-09T00:00:00Z Studies of Volvox, an alga that forms beautiful, flagellated green balls, shows that multicellular organisms also found new ways to use existing functions. The momentous transition to multicellular life may not have been so hard after all 2018-06-28T04:00:00Z “It’s a fleshy organ, rich in nerve endings, taste buds, and multicellular glands,” Finucci says. Mysterious Ghost Sharks' Sex Habits Revealed 2017-06-12T04:00:00Z Researchers on Tuesday described the tiny, multicellular fossils as two types of red algae, one thread-like and the other bulbous, that lived in a shallow marine environment alongside mats of bacteria. Fossils from 1.6 billion years ago may be oldest-known plants 2017-03-14T04:00:00Z Plants and insects are the most diverse multicellular organisms on Earth, and they provide the foundation for most terrestrial food webs. How long did it take for life to rebound after the death of the dinosaurs? 2016-11-07T05:00:00Z The evolution of cellular communication is an absolute necessity for the development of multicellular organisms, and this innovation is thought to have required approximately 2.5 billion years to appear in early life forms. Biology for AP Courses 2022-06-09T00:00:00Z Instead, features and functions seen in single-celled organisms are rearranged in time and space in their multicellular relatives, says Corina Tarnita, a theoretical biologist at Princeton University. The momentous transition to multicellular life may not have been so hard after all 2018-06-28T04:00:00Z When you consider the biology of cancer, it is no surprise to find it in early hominins or any form of multicellular life. The Known: Cancer Is Really, Really Old. The Unknown: How Common It Was. 2016-08-22T04:00:00Z The fossils also represent the oldest-known advanced multicellular organisms in the broad category called eukaryotes that includes plants, fungi and animals, indicating complex life flourished much earlier than previously assumed, the researchers said. Fossils from 1.6 billion years ago may be oldest-known plants 2017-03-14T04:00:00Z Over millions of years, they might evolve into multicellular organisms, and, perhaps eventually, plants and animals. Q&A: Should we seed life on alien worlds? 2016-09-09T04:00:00Z The zygote will undergo multiple rounds of mitosis to produce a multicellular offspring. Biology for AP Courses 2022-06-09T00:00:00Z Within 2 months, multicellular clusters began to appear, as newly formed daughter cells stuck to their mothers and formed branching structures. The momentous transition to multicellular life may not have been so hard after all 2018-06-28T04:00:00Z Yet, though a few multicellular animals do predate 575m years ago, all those discovered so far are microscopic. Time capsules 2016-07-28T04:00:00Z It’s well known that the transfer of mitochondrial DNA from mother to offspring, often called maternal inheritance, occurs in humans and most multicellular organisms. Why Do We Inherit Mitochondrial DNA Only From Our Mothers? 2016-06-23T04:00:00Z Perhaps the most intriguing, indirect evidence for the rise of eukaryotic predators was the appearance of simple, multicellular organisms. You May Owe Your Existence to Tiny Vampires 2016-06-09T04:00:00Z The haploid cells that make up the tissues of the dominant multicellular stage are formed by mitosis. Biology for AP Courses 2022-06-09T00:00:00Z Only after oxygen levels rose about 1 billion years ago could larger, multicellular organisms arise. The momentous transition to multicellular life may not have been so hard after all 2018-06-28T04:00:00Z Truly multicellular creatures display three-dimensional form in which only some cells are in direct contact with the environment. Complex life on Earth began billion years earlier than previously thought, study argues 2016-05-17T04:00:00Z In Thompson’s analogy, the Warburg effect can be thought of as a social failure: a breakdown of the nutrient-sharing agreement that single-celled organisms signed when they joined forces to become multicellular organisms. An Old Idea, Revived: Starve Cancer to Death 2016-05-12T04:00:00Z These early, multicellular colonies enabled the evolution of more complex plants and animals, including us. You May Owe Your Existence to Tiny Vampires 2016-06-09T04:00:00Z The zygote will undergo many rounds of mitosis and give rise to a diploid multicellular plant called a sporophyte. Biology for AP Courses 2022-06-09T00:00:00Z The evolutionary histories of some groups of organisms record repeated transitions from single-celled to multicellular forms, suggesting the hurdles could not have been so high. The momentous transition to multicellular life may not have been so hard after all 2018-06-28T04:00:00Z Another researcher, Abderrazak El Albani of the University of Poitiers in France, said the level of detail in the study was “ absolutely insufficient to tell us if these organisms were multicellular, eucaryotes or complex”. Complex life on Earth began billion years earlier than previously thought, study argues 2016-05-17T04:00:00Z "If you're a multicellular organism, all of your cells are cooperating, behaving altruistically, working together for the benefit of the whole," Durand said. This gene helps prevent cancer. Did it also give rise to all complex life? 2016-04-26T04:00:00Z The animals in question are descendants of some of Earth's oldest multicellular life forms. The secret lives of jellyfish 2016-03-21T04:00:00Z Figure 11.10 Plants have a life cycle that alternates between a multicellular haploid organism and a multicellular diploid organism. Biology for AP Courses 2022-06-09T00:00:00Z If, as she and others believe, choanoflagellates offer a glimpse of the one-celled ancestor of animals, that organism was already well-equipped for multicellular life. The momentous transition to multicellular life may not have been so hard after all 2018-06-28T04:00:00Z “They are not the oldest eukaryotes, but they are certainly the oldest demonstrably multicellular eukaryotes,” he said. Complex life on Earth began billion years earlier than previously thought, study argues 2016-05-17T04:00:00Z Cancer has probably existed ever since our first multicellular ancestors appeared on Earth hundreds of millions of years ago. Scientists Ponder the Prospect of Contagious Cancer 2016-02-22T05:00:00Z That places the black hole merger in very deep space; the signal that arrived in September came from an event that happened before there were any multicellular organisms on Earth. Cosmic breakthrough: Physicists detect gravitational waves from violent black-hole merger 2016-02-11T05:00:00Z After 60 generations of repeated selection, yeast became multicellular. Biology for AP Courses 2022-06-09T00:00:00Z The same goes for algae: Red, brown, and green algae all evolved their own multicellular forms over the past billion years or so. The momentous transition to multicellular life may not have been so hard after all 2018-06-28T04:00:00Z They resurrected ancient molecules that once helped single-celled organisms thrive, then recreated the mutations that helped them build multicellular bodies. Genetic Flip Helped Organisms Go From One Cell to Many 2016-01-07T05:00:00Z Such life signatures did not require multicellular organisms, let alone intelligent creatures. Beyond 550 astronomical units : Nature : Nature Publishing Group 2015-12-01T05:00:00Z But when they starve, they aggregate and form a multicellular body that crawls toward light and ultimately coalesces into a structure called a fruiting body. The Woman Who Stared at Wasps 2015-12-01T05:00:00Z Specialization in multicellular animals contributes to efficiency in cell processes. Biology for AP Courses 2022-06-09T00:00:00Z "What this group of algae has taught us is some of the steps involved in the evolution of a multicellular organism," says Matthew Herron, an evolutionary biologist at the Georgia Institute of Technology in Atlanta. The momentous transition to multicellular life may not have been so hard after all 2018-06-28T04:00:00Z The transition from our single-celled ancestors to the first multicellular animals occurred about 800 million years ago, but scientists aren’t sure how it happened. Genetic Flip Helped Organisms Go From One Cell to Many 2016-01-07T05:00:00Z That includes the 'Cambrian explosion' in multicellular diversity and the first discoverable remains of animal ancestral phyla. 500-Million-Year-Old Brains and Life in the Universe 2015-11-13T05:00:00Z But if the Dictyostelium cells in that multicellular body aren’t all genetically identical, are some sacrificing themselves for others with whom they have nothing in common? The Woman Who Stared at Wasps 2015-12-01T05:00:00Z When genome-editing tools are applied to multicellular embryos, only some of the cells may be altered, resulting in a genetic mosaic of edited and unedited cells. CRISPR: A path through the thicket 2015-11-09T05:00:00Z The gulf between unicellular and multicellular life seems almost unbridgeable. The momentous transition to multicellular life may not have been so hard after all 2018-06-28T04:00:00Z Other adaptations were needed in order to grow multicellular bodies. Genetic Flip Helped Organisms Go From One Cell to Many 2016-01-07T05:00:00Z That was a conundrum: although the US investigators knew about the man's tapeworm infection, the invading cells did not look like they should belong to a complex, multicellular organism such as a tapeworm. The tapeworm that turned into a tumour 2015-11-03T05:00:00Z Neither plant nor animal, these single-cell amoebas feed on bacteria but aggregate when their food source becomes scarce to form glossy, bulbous, shape-shifting multicellular plasmodia that develop fruiting bodies. 'Creeping Garden' documentary covers slime mold with style instead of substance 2015-10-27T04:00:00Z Since multicellular life clearly is possible, some sort of repair mechanism must exist. Wisdom, ancient and modern 2015-10-07T04:00:00Z Likewise, fossil spores suggest multicellular plants evolved from algae at least 470 million years ago. The momentous transition to multicellular life may not have been so hard after all 2018-06-28T04:00:00Z They cooperated instead, sharing resources and responsibilities and so giving rise to multicellular creatures — plants, animals and eventually us. Cellular Cheaters Give Rise to Cancer 2015-07-27T04:00:00Z Fundamental new patterns are emerging that may be compared, say, with the change, half a billion years ago, when a biosphere consisting only of microbes gave way to one dominated by multicellular animals. The Earth stands on the brink of its sixth mass extinction and the fault is ours 2015-06-20T04:00:00Z The process involves identifying "key architectural and compositional elements" of the targeted tissue and creating a specially formulated "bio-ink," or multicellular building block, for it. L'Oreal partners with bioprinting company to 3D print human skin 2015-05-18T04:00:00Z It is the most ancient of animal perceptions, most likely evolved from the earliest days of multicellular life. Book Review: “Tasty: The Art and Science of What We Eat” 2015-05-15T04:00:00Z One of the most striking examples is a moment in the development of Volvox, a kind of algae that forms one of the simplest multicellular organisms. Birth? Trivial Next to Cellular Doughnut-Making Process 2015-05-04T04:00:00Z What is clear from the abundance of examples is that multicellular life is a continual struggle between competition and cooperation. Cellular Cheaters Give Rise to Cancer 2015-07-27T04:00:00Z The centre also changed its Japanese name to “centre for research into the formation of multicellular systems”, although it kept its original English name. Collateral damage: How one misconduct case brought a biology institute to its knees 2015-04-28T04:00:00Z And we have them living in our guts, in our intestines, in our stomachs, and so does every multicellular life form. Harnessing the Power of Human Waste to Survive 2015-03-08T05:00:00Z How likely is it that simple, microbial life will evolve into complex, multicellular organisms and eventually into creatures with large brains? Is there life beyond Earth? Do we even want to know? 2015-02-28T05:00:00Z The really interesting thing is, as more complex life evolves – that is, multicellular life with mouths, brains, and internal organs – taste and smell play a central role. How the Sense of Taste has Shaped Who We Are 2015-01-13T05:00:00Z It was the shift to eukaryotism, sometime between two billion and one billion years ago, that opened the path to complex, multicellular life and thus, eventually, to human beings. Nuclear reaction 2014-11-06T05:00:00Z A class on the emergence of life might start with photosynthesis before moving on to eukaryotes and multicellular organisms and the genius of Charles Darwin and James Watson. So Bill Gates Has This Idea for a History Class . . . 2014-09-05T04:00:00Z The new organisms are multicellular but mostly non-symmetrical, with a dense layer of gelatinous material between the outer skin cell and inner stomach cell layers. Deep sea 'mushroom' is a breed apart 2014-09-03T04:00:00Z In multicellular organisms, transcription factors bind at cis-regulatory elements in the genome to mediate diverse gene expression programs with exquisite spatiotemporal control1, 2, 3. Regulatory analysis of the C. elegans genome with spatiotemporal resolution : Nature : Nature Publishing Group 2014-08-26T04:00:00Z But the low rate of carbon fixation by microbes might provide too little food for multicellular life. Lakes under the ice: Antarctica’s secret garden 2014-08-19T04:00:00Z But most of the living things on the planet are microorganisms, with us large multicellular animals forming a thin layer on the top. Back to the future with antibiotic resistance 2014-07-21T04:00:00Z In a 2011 Nature paper, Strother and his co-investigators reported direct evidence that multicellular structures may have dominated freshwater terrestrial settings by 1 billion years ago, half a billion years before the Cambrian explosion. Death Valley's First Life Came by Land, Not by Sea 2014-04-28T20:40:00Z Because trogocytosis is seen in both amoebae and humans, this might be evolutionarily ancient, "dating back well before multicellular organisms evolved," Petri said. Amoeba Takes Bites of Human Cells to Kill Them 2014-04-09T19:38:00Z On the other hand, consider that, at a few hundred micrometers long, this complex multicellular arthropod is roughly the same size as some large single-celled microbes like amoebae. New Worm-Like Mite Features Extraordinary Upholstery 2014-03-31T21:06:12Z In multicellular organisms, morphogen signaling proteins move from “signaling centers” where they are produced to target cells whose growth and patterning they regulate. [Research Article] Cytoneme-Mediated Contact-Dependent Transport of the Drosophila Decapentaplegic Signaling Protein 2014-02-20T19:25:43.644Z For instance, all multicellular life may possess cellular junctions — basically, doors between cells — that help the cells in a single organism talk to each other and coordinate their activities. An Illustration of the Many Ways to Be Multicellular on Planet Earth 2014-02-19T16:08:13Z He is also convinced that multicellular oxygen breathers — the ancestors of modern animals — may well have lived in and fed upon photosynthesizing microbes that were spewing millions of tons of oxygen into the atmosphere. Death Valley's First Life Came by Land, Not by Sea 2014-04-28T20:40:00Z In multicellular organisms, biological function emerges when heterogeneous cell types form complex organs. [Report] Massively Parallel Single-Cell RNA-Seq for Marker-Free Decomposition of Tissues into Cell Types 2014-02-13T19:26:01.362Z From circuits to multicellular behaviors: a bottom-up synthesis of hierarchy. [Research Article] Secreting and Sensing the Same Molecule Allows Cells to Achieve Versatile Social Behaviors 2014-02-06T19:26:19.049Z A much more reasonable assumption is that until proved otherwise, many, if not all, multicellular organisms experience and pleasure and can see and hear the sights and sounds of life. Is Consciousness Universal? 2014-01-01T05:45:00.400Z Biologists don’t actually agree on what it means to be a multicellular organism, which you might define simply as being an organism made up of more than one cell. An Illustration of the Many Ways to Be Multicellular on Planet Earth 2014-02-19T16:08:13Z The result of the earth's remarkable oxygenation over geological time is nothing less than our planet's rich biosphere of complex, multicellular life. Book Review: Oxygen 2013-12-27T13:45:02.073Z The phenomenon, called mechanotaxis, helps create multicellular structures such as our organs. Bacteria Could Be Living Structural Sensors 2013-12-26T13:15:00.462Z Our first-principles approach may be generalized to reveal relationships between the structures of other fundamental cell-signaling circuits and the multicellular behaviors that they enable. [Research Article] Secreting and Sensing the Same Molecule Allows Cells to Achieve Versatile Social Behaviors 2014-02-06T19:26:19.049Z Cassandra Extavour: As a developmental biologist — a devo, if you will — I am intrigued by how cells become eggs and sperm in multicellular creatures. Debate on Evolution of Multicellular Organisms Starts to Gain Focus 2013-09-30T22:45:00.843Z How many ways are there to be multicellular on Earth? An Illustration of the Many Ways to Be Multicellular on Planet Earth 2014-02-19T16:08:13Z Then in stage two, about 500 million years ago, he says earth had an onset of lots of multicellular complex life. Oxygen's Ancient Rise Still One Of Earth's Biggest Mysteries 2013-09-01T00:50:00Z The work is part of a multi-university research project, financed by the National Science Foundation, to develop multicellular devices with applications in health care, security and other fields. Printing Out a Biological Machine 2013-08-18T18:13:04Z They begin life as swimming multicellular larvae made of individual cells as other sponges do. Glass Sponges Poriferify -- and Beautify -- Impoverished Antarctic Neighborhood 2013-08-08T22:45:13.887Z To be clear: There is no conscious goal or direction or systemic intentionality built into the evolutionary trajectory of a given entity, be it unicellular or multicellular. Debate on Evolution of Multicellular Organisms Starts to Gain Focus 2013-09-30T22:45:00.843Z Back then, most of the world's multicellular creatures lived in the sea. Tiny Plants That Once Ruled the Seas (preview) 2013-05-15T11:15:00.233Z In animals, the resulting diploid cell — a zygote — goes on to divide asexually many times, forming the multicellular organism. Mosses Make Two Different Plants From the Same Genome, and a Single Gene Can Make the Difference 2013-05-12T19:45:00.233Z In addition, there are plenty of multicellular species that we know exist in the human microbiome. Ten Predictions for the Future of Your (Microbial) Health 2013-03-19T12:45:03.283Z Many fewer microbes share the species name mirabilis than multicellular organisms, but one is—in my opinion—particularly remarkable. The Taxonomy of Wonder 2013-03-01T14:45:05.380Z I grant, though, that biologists must be fascinated by the evolution of multicellularity, because we are multicellular creatures. Debate on Evolution of Multicellular Organisms Starts to Gain Focus 2013-09-30T22:45:00.843Z The ability of some to regenerate tissue is generally considered to be an ancient quality of all multicellular animals. Newt Finding Might Set Back Efforts to Regrow Human Limbs 2013-02-21T22:15:02.213Z In this lifestyle, a single copy of the genome produces one multicellular organism. Mosses Make Two Different Plants From the Same Genome, and a Single Gene Can Make the Difference 2013-05-12T19:45:00.233Z As multicellular life developed, these early life forms were outcompeted and restricted to fewer and fewer places. Scientist at Work Blog: Diving an Antarctic Time Capsule Filled With Primordial Life 2013-01-31T17:54:18Z Here is an organism that is both solitary and fully, suicidally social, a nearly perfect model creature for understanding how multicellular life emerged from the amoebae. What is it? Social Cells 2013-01-26T05:45:00.240Z The division of reproductive labor in a multicellular entity requires that cells work together to maximize the reproductive potential of the entity of which they are a part. Debate on Evolution of Multicellular Organisms Starts to Gain Focus 2013-09-30T22:45:00.843Z But most multicellular fungi, the assumption goes, don’t senesce. Studying Seemingly Immortal Lichens, in a Place for the Dead 2012-12-31T19:13:21Z A multicellular slug of sorts, the group grows into a spore-making tower, a beacon for broadcasting amoebae out to richer grounds. Starving to be Social: The Odd Life of Dictyostelium Slime Molds 2012-11-26T21:15:00.210Z Added to which, cells inside a multicellular organism don’t really need to sense what’s going on, they get told what’s going on by the surrounding cells and circulating hormones. How the animals lost their sensors 2012-11-25T17:45:00.383Z It is so fundamental to life and multicellular systems that it can't not be involved in cancer'.” Mechanics: The forces of cancer 2012-11-23T15:20:56.230Z Extavour's special expertise is in tracking the development of germ cells, the cells created in an embryo that contain the genetic code for reproducing multicellular organisms. Debate on Evolution of Multicellular Organisms Starts to Gain Focus 2013-09-30T22:45:00.843Z Early in his career, Leonard untangled the taxonomic mess of similar-looking, but only distantly related, fungi with multicellular dark spores that were causing disease in grains such as corn. Fungal Meningitis Pathogen Discovers New Appetite for Human Brains 2012-11-12T11:45:00.180Z Here is an organism that is both solitary and fully, suicidally social, a near perfect model creature for understanding how multicellular life emerged from the amoebae. Starving to be Social: The Odd Life of Dictyostelium Slime Molds 2012-11-26T21:15:00.210Z Since, in a multicellular organism, different cells need different genes to be active, such regulation is vital. Epigenetics and health: Grandma’s curse 2012-11-01T16:03:12Z For more complex, multicellular life, scientists often adhere to the biological definition of a species—two groups become so genetically distinct they cannot interbreed. See Change: Rapid Emergence of New Sea Star Species Illustrates Evolution's Power 2012-08-10T15:45:02.653Z Eventually, some of those individuals teamed up and became complex multicellular organisms. The Evolution Of Human Systems 2012-07-31T14:02:17Z They became eukaryotic cells, the kind of cells that all multicellular animals are made from. The origin of breathing: how bacteria learnt to use oxygen 2012-07-29T22:15:00.207Z Over the next few billion years, single-celled organisms fused and became multicellular; body plans diversified and radiated, exploding into an array of invertebrates. Evolution: Out Of The Sea 2012-07-29T03:15:04.080Z Single-celled organisms incorporated these trace metals into metal-binding proteins that ultimately enabled the diversification of multicellular life, the researchers speculate online this month in Geology. You Owe Your Life to Rock 2012-06-15T19:48:11Z Like all multicellular animals, insects fuel their metabolism by taking in oxygen. Where Have the Hawk-Sized Insects Gone? 2012-06-04T20:02:00Z The Bacteria that Commit Honourable Suicide In multicellular organisms it is essential that every cell behaves and does the job it was produced to perform. The Bacteria that Commit Honourable Suicide 2012-05-27T19:45:00.430Z Sexual Phenomena in Higher Forms.—In the reproduction of multicellular organisms, one sees likewise but a continuation of the phenomena exhibited in Volvox. Being Well-Born An Introduction to Eugenics 2012-05-22T15:16:53.140Z All other animals and all the higher plants are multicellular. The Contemporary Review, Volume 36, October 1879 2012-04-18T02:00:17.060Z Most multicellular organisms would agree it was a good move. Mitiochondria Are Related to Ocean Bacteria, But Not to the Ones We Thought 2012-04-16T19:45:00.240Z Each of these functions is crucial to the survival and function of a multicellular animal. Cancer: Solving an age-old problem 2012-02-29T18:21:13.613Z In multicellular individuals the division of labour to which the structural complexity of the organism is due is between the individual cell-units, some cells developing one 712 aspect, some another, of their vital attributes. Encyclopaedia Britannica, 11th Edition, Volume 7, Slice 8 "Cube" to "Daguerre, Louis" 2012-01-31T03:00:17.257Z These two kinds of reproductive cells in multicellular organisms are derived ordinarily from two separate individuals known as male and female, though there are some exceptions. Being Well-Born An Introduction to Eugenics 2012-05-22T15:16:53.140Z The researchers also found evidence of rudimentary division of labor, which is an essential characteristic for more complex multicellular life forms. Test Tube Yeast Evolve Multicellularity 2012-01-16T21:15:03.510Z It’s a big step for evolution, going from a single cell focused solely on its own survival to a multicellular organism where cells coordinate and work together. Evolution: The Rise of Complexity 2012-01-16T21:15:00.253Z This sponge tells us that the potential to develop cancer is not new: sponges are some of the oldest multicellular animals and existed 635 million years ago. Cancer: Solving an age-old problem 2012-02-29T18:21:13.613Z In all cases, however, whether the cell-unit lives freely as a unicellular organism or forms an integral part of a multicellular individual, it exhibits in itself all the phenomena characteristic of living things. Encyclopaedia Britannica, 11th Edition, Volume 7, Slice 8 "Cube" to "Daguerre, Louis" 2012-01-31T03:00:17.257Z Once the cells gain the ability to form snowflakes, they become better adapted to multicellular life. Yeast Reveals How Fast a Cell Can Form a Body 2012-01-16T20:50:06Z In the multicellular yeast, the division of labor was more subtle. Test Tube Yeast Evolve Multicellularity 2012-01-16T20:15:00.203Z These clumps weren’t just independent cells sticking together for the sake of it – they acted as rudimentary multicellular creatures. Evolution: The Rise of Complexity 2012-01-16T21:15:00.253Z All multicellular organisms rely on cooperation and communication among their cells. Cancer: Solving an age-old problem 2012-02-29T18:21:13.613Z It is evident therefore that in the multicellular forms all the complex manifestations of life are but the outcome of the co-ordinated activities of the constituent cells. Encyclopaedia Britannica, 11th Edition, Volume 7, Slice 8 "Cube" to "Daguerre, Louis" 2012-01-31T03:00:17.257Z Dr. Ratcliff suspects that the transformation of the yeast in his lab may offer hints about how animals and other lineages became multicellular hundreds of millions of years ago. Yeast Reveals How Fast a Cell Can Form a Body 2012-01-16T20:50:06Z The transition from single-celled to multicellular organisms was one of the most significant developments in the history of life on Earth. Test Tube Yeast Evolve Multicellularity 2012-01-16T20:15:00.203Z But what is even more incredible is that they were the first to do something extraordinary – they were the first cells to join forces and create multicellular life. Evolution: The Rise of Complexity 2012-01-16T21:15:00.253Z But it also tells us that cancer is an unfortunate consequence of multicellular life. Cancer: Solving an age-old problem 2012-02-29T18:21:13.613Z Cell-differentiation.—Both among unicellular and multicellular individuals the cell assumes the most varied forms and performs the most diverse functions. Encyclopaedia Britannica, 11th Edition, Volume 7, Slice 8 "Cube" to "Daguerre, Louis" 2012-01-31T03:00:17.257Z It begins when unicellular develop into multicellular organisms. Human Personality and its Survival of Bodily Death 2012-01-05T03:00:42.307Z In a true multicellular organism, such as a rabbit, evolution acts upon the rabbit and not upon each of the billions of cells that build it. Test Tube Yeast Evolve Multicellularity 2012-01-16T20:15:00.203Z The megaspore 763 is filled with tissue as in typical Gymnosperms, and from some of the superficial cells 3 to 5 archegonia are developed, characterized by long multicellular necks. Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 7 "Gyantse" to "Hallel" 2011-12-26T03:00:11.613Z Some of these are large multicellular bacterial groups, while others are single-celled large and rod-shaped. New Magnetic Bacteria! 2011-12-23T18:45:16.900Z It is possible to suggest a mechanico-physical explanation of multicellular structure which will deprive the cell of much of its assumed significance as a unit of organization. Encyclopaedia Britannica, 11th Edition, Volume 7, Slice 8 "Cube" to "Daguerre, Louis" 2012-01-31T03:00:17.257Z On no hypothesis can we really understand the collaboration and subordination of the cell-lives of any multicellular animal. Human Personality and its Survival of Bodily Death 2012-01-05T03:00:42.307Z A famous collection of minute 570-million-year-old fossils, from the Doushantuo Formation in southern China, has long been thought to hold some of the earliest evidence of multicellular animal development: primitive embryos. 3-D Imaging of Microfossils Muddies Case for Early Animal Embryos [Video] 2011-12-23T00:15:02.737Z Every living cell has psychic properties, and the psychic life of multicellular organisms is the sum-total of the psychic functions of the cells of which they are composed. Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 7 "Gyantse" to "Hallel" 2011-12-26T03:00:11.613Z It culminated in what is known as the Cambrian explosion, about 550 million years ago, when multicellular creatures, that is to say, animals, appeared in sudden splendiferous profusion in the fossil record. Life Out There: Scientists Are Hot on Trail of Exoplanets Suitable for Life 2011-12-03T04:00:20Z The very elaborate regional differentiation of the protoplasm often seen in the Protozoa sufficiently indicate that multicellular structure is no essential condition for complex regional differentiation. Encyclopaedia Britannica, 11th Edition, Volume 7, Slice 8 "Cube" to "Daguerre, Louis" 2012-01-31T03:00:17.257Z It is the first vaccine against a complex multicellular parasite, Plasmodium falciparum, to consistently show a significant protective effect in large-scale trials. Malaria vaccine results face scrutiny 2011-10-26T17:20:44.570Z At first, evolution was slow, becoming more rapid in the past 550 million years as single-cell organisms coalesced to form multicellular organisms. Biochemistry without boundaries 2011-10-12T17:20:58.527Z Some species gather by the thousands to form multicellular bodies that can crawl. Slime Molds: Ancient, Alien and Sophisticated 2011-10-03T20:59:02Z Because the appearance of molecules that maintain our fluid balance coincide with the evolution of multicellular life. Electrolyte Balancers Set Stage For Multicellularity 2011-09-26T21:15:02.267Z The result eventually is this multicellular individual composed of a number of different kinds of cells each set apart for its own work. Embryology The Beginnings of Life 2011-09-12T02:00:28.483Z And they may get better thanks to living cells: the multicellular organism called brown algae. Batteries Could Get Algae Boost 2011-09-09T19:45:03.277Z Until the vendobionts went extinct, he argues, multicellular animals "lived in the shadow of these unicellular giants". Ancient sea jelly makes tree of life wobble 2011-09-07T23:45:07.457Z An intermediate stage which may serve towards the explanation of these circumstances is presented by the lower multicellular organisms, such as threadlike algæ, fungi, and other simple creatures. The Biological Problem of To-day Preformation Or Epigenesis? The Basis of a Theory of Organic Development 2011-08-29T02:01:04.170Z And they found that two proteins—a sodium channel and part of a sodium pump—arose slightly before the first multicellular . Electrolyte Balancers Set Stage For Multicellularity 2011-09-26T21:15:02.267Z It passes through the stage of a single cell, then becomes multicellular, and gradually assumes the form of a higher and higher type of organism. Embryology The Beginnings of Life 2011-09-12T02:00:28.483Z The fertilized egg enlarges and becomes multicellular, forming the embryo. Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 3 "Frost" to "Fyzabad" 2011-08-15T02:00:28.473Z In addition, when the cells from the postchemotherapy biopsies were grown in suspension, they formed more multicellular balls than the prechemotherapy ones, something only stem cells typically do. How Do Tumors Grow? 2011-08-04T12:45:04.617Z We can now see the chief requirements to which the constitution and arrangement of the cells in a multicellular plant must be adapted. The Biological Problem of To-day Preformation Or Epigenesis? The Basis of a Theory of Organic Development 2011-08-29T02:01:04.170Z But once a creature is multicellular, things are more complex. Electrolyte Balancers Set Stage For Multicellularity 2011-09-26T21:15:02.267Z Once you get multicellular animals, models show intelligence is likely in a few hundred million years. Event horizon 2011-07-20T17:20:33.377Z The basidium is a unicellular or multicellular structure from which four basidiospores arise as outgrowths; it starts as a binucleate structure, but soon, like the ascus, becomes uninucleate by the fusion of the two nuclei. Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 3 "Frost" to "Fyzabad" 2011-08-15T02:00:28.473Z Function, of course, involves activity; and activity, in a complex, multicellular organism, involves the interplay of parts. Household Administration Its Place in the Higher Education of Women 2011-07-20T02:00:13.547Z Therefore, unlike plants, multicellular animals display a compact structure with internal organs adapted to the different conditions which result from the method of nutrition peculiar to animals. The Biological Problem of To-day Preformation Or Epigenesis? The Basis of a Theory of Organic Development 2011-08-29T02:01:04.170Z Single cells merge into multicellular organisms of specialized parts. Thirst for Fairness May Have Helped Us Survive 2011-07-04T16:37:45Z The phylum Porifera or Spongi� includes the simplest of the Metazoa or multicellular animals. Freshwater Sponges, Hydroids & Polyzoa 2011-06-25T02:00:17.833Z The protoplasm then becomes cut up by a series of clefts into a number of smaller and smaller pieces which are unicellular in Pilobolus, multicellular in Sporodinia. Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 3 "Frost" to "Fyzabad" 2011-08-15T02:00:28.473Z We must not, however, confine attention to the higher multicellular animals and plants. Household Administration Its Place in the Higher Education of Women 2011-07-20T02:00:13.547Z Differentiation in multicellular organisms takes a similar course. The Biological Problem of To-day Preformation Or Epigenesis? The Basis of a Theory of Organic Development 2011-08-29T02:01:04.170Z He calls the findings “eye opening” and expects they will encourage other researchers to start looking for multicellular creatures far beneath Earth’s surface. Hungry Worms From Hell 2011-06-01T21:12:58Z The authors of the study expect to find other multicellular animals far beneath our planet's surface, and are preparing to descend again to search for others. Deepest-living land animal found 2011-06-02T14:35:47Z But until now, it was thought that the temperature, energy, oxygen and space constraints of the subsurface biosphere were too extreme for multicellular organisms. Observatory: Treasure Is Found Deep in a Gold Mine: A New Worm 2011-06-01T21:45:46Z The nematodes recovered from gold-mine workings under South Africa — reported on of this issue — are the first multicellular organisms to be discovered in such a subterranean setting. Gold mine 2011-06-01T17:20:04.803Z Weismann believes himself to have established a fundamental distinction between unicellular and multicellular organisms. The Biological Problem of To-day Preformation Or Epigenesis? The Basis of a Theory of Organic Development 2011-08-29T02:01:04.170Z Marine microbiologist Andreas Teske of the University of North Carolina, Chapel Hill, was not surprised that the first multicellular subsurface organism was a nematode; the worms are among the hardiest creatures on the planet. Hungry Worms From Hell 2011-06-01T21:12:58Z So it wasn't a surprise to him that the first multicellular organism to be found in the deep subsurface of the Earth was a worm. Deepest-living land animal found 2011-06-02T14:35:47Z At about 4 billion, multicellular organisms would arise. Why Older Planets Are More Likely to Harbor Life 2011-06-01T10:00:00Z How, then, do these single-celled intestinal denizens exert their influence on a complex multicellular organ such as the brain? The Neuroscience of the Gut 2011-04-19T15:15:00.413Z For, according to our definition of the cell, a multinucleated organism potentially is a multicellular organism. The Biological Problem of To-day Preformation Or Epigenesis? The Basis of a Theory of Organic Development 2011-08-29T02:01:04.170Z A ravenous predator also survives in these hellish conditions: a roundworm that researchers describe today as the first multicellular organism to be found in the deep subsurface of Earth. Hungry Worms From Hell 2011-06-01T21:12:58Z In the transition to full-blown animals, Dr. King argues, these genes were co-opted for controlling a multicellular body. From Single Cells, a Vast Kingdom Arose 2011-03-14T22:00:25Z “It actually should be thought of as a multicellular organism with a very large genome,” he adds. Diversity: Of beans and genes 2011-01-04T21:23:19.127Z And in fact, some choanoflagellates do form multicellular colonies at stages of their life cycle. Remarkable Creatures: In a Single-Cell Predator, Clues to the Animal Kingdom?s Birth 2010-12-14T16:46:36Z Weismann's conception, therefore, implies that many of the lower multicellular organisms, having no somatic-cells, have no body. The Biological Problem of To-day Preformation Or Epigenesis? The Basis of a Theory of Organic Development 2011-08-29T02:01:04.170Z The finding adds to the growing notion that groups of bacteria might behave more like a multicellular organism than traditionally thought, he says. Hints of Altruism Among Bacteria 2010-09-02T14:53:00Z If organisms are to be multicellular, cells must be able to talk to each other. Diet and the evolution of the brain: Fish and no chips 2010-05-27T11:06:00Z The same transformation of the reproductive cells into non-separable tissue cells is repeated several times in multicellular plants and serves to enlarge the individual. A Mechanico-Physiological Theory of Organic Evolution Whatever the explanation, the presence of those genes in a unicellular organism indicates that much of the machinery for making multicellular animals was in place long before the origin of animals. Remarkable Creatures: In a Single-Cell Predator, Clues to the Animal Kingdom?s Birth 2010-12-14T16:46:36Z Clearly enough, the egg, in its single-celled condition, changes its quality in a marked degree when it becomes multicellular, even although the change has occurred by doubling division. The Biological Problem of To-day Preformation Or Epigenesis? The Basis of a Theory of Organic Development 2011-08-29T02:01:04.170Z A growth both of the funnel, which becomes multicellular, and of the rest of the nephridium produces the adult nephridia of the genera mentioned. Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 7 "Cerargyrite" to "Charing Cross" With the multicellular organisms much variation in form is possible, but with these single-celled organisms the possible variation in form is greatly limited. Outlines of dairy bacteriology A concise manual for the use of students in dairying The phylogenetic significance of the alternation of generations consists in its representing a transition stage from the unicellular to the simpler multicellular and from the latter to the more complex multicellular plants. A Mechanico-Physiological Theory of Organic Evolution Scientists are eager to understand how transitions from a unicellular to multicellular lifestyle were accomplished. Remarkable Creatures: In a Single-Cell Predator, Clues to the Animal Kingdom?s Birth 2010-12-14T16:46:36Z But I must insist here that the subordination of the cells to the whole organism, in both multicellular animals and in plants, is much more complicated than that of the units to the human state. The Biological Problem of To-day Preformation Or Epigenesis? The Basis of a Theory of Organic Development 2011-08-29T02:01:04.170Z A very instructive example is furnished by the case of volvox, a multicellular vegative organism of very curious habits. The Truth About Woman In spite of the great complication of the divers living multicellular organisms, one often finds among them the power of reproduction by fission or by budding. The Sexual Question A Scientific, psychological, hygienic and sociological study Later the cell generations of an ontogeny are united by parts into plant individuals; the ontogenetic period consists of a cycle of multicellular and unicellular, or only of multicellular plant generations. A Mechanico-Physiological Theory of Organic Evolution Now, it is only in the multicellular organisms that there is any observable distinction of sex. Darwin, and After Darwin (Vol. 1 and 3, of 3) An Exposition of the Darwinian Theory and a Discussion of Post-Darwinian Questions Since such a creature as the rabbit is formed through the co-operation of a vast multitude of cells, it is called multicellular; the amoeba, on the other hand, is unicellular. Text Book of Biology, Part 1: Vertebrata The multicellular organism was a colony of unicellular organisms, and its life was a sum of the lives of its constituent elements. Form and Function A Contribution to the History of Animal Morphology Among multicellular animals, sometimes in the same individual, sometimes in different individuals, occur two kinds of sexual glands, each containing one kind of cells—the male cells and the female cells. The Sexual Question A Scientific, psychological, hygienic and sociological study In multicellular animals the cells are of different kinds with different functions. The Outline of Science, Vol. 1 (of 4) A Plain Story Simply Told Thus far, then, the phenomena of multiplication are identical in all the lowest or unicellular organisms, and in the constituent cells of all the higher or multicellular. Darwin, and After Darwin (Vol. 1 and 3, of 3) An Exposition of the Darwinian Theory and a Discussion of Post-Darwinian Questions The low unicellular organisms are potentially immortal, the higher multicellular forms with well-differentiated organs contain the germs of death within themselves. The Birth-Time of the World and Other Scientific Essays The unicellular organism can by its very nature transform itself into a multicellular organism only by the method of cell-division. Form and Function A Contribution to the History of Animal Morphology It had been assumed that the body of the multicellular animal or plant was made of independent units. The Story of the Living Machine A Review of the Conclusions of Modern Biology in Regard to the Mechanism Which Controls the Phenomena of Living Activity Thus, as in indubitable multicellular animals, division of labour has begun. The Outline of Science, Vol. 1 (of 4) A Plain Story Simply Told For the distinction is clearly one which must necessarily arise, if the doctrine of continuity between unicellular and multicellular organisms be true. Darwin, and After Darwin (Vol. 1 and 3, of 3) An Exposition of the Darwinian Theory and a Discussion of Post-Darwinian Questions By the development of this process, multicellular metazoa arose from the colonies of similar protozoa, and at length culminated in the higher animals and man. Scientific American Supplement, No. 810, July 11, 1891 III But we must proceed to examine the behavior of the various kinds of cells of which the various multicellular organisms are composed. Q. E. D., or New Light on the Doctrine of Creation As the different cells in the multicellular mass became associated into groups for different duties, the method of such division of labor was not alike in all machines. The Story of the Living Machine A Review of the Conclusions of Modern Biology in Regard to the Mechanism Which Controls the Phenomena of Living Activity Among simple multicellular animals, such as sea-anemones, we find the beginnings of reflex actions, and a considerable part of the behaviour of the lower animals is reflex. The Outline of Science, Vol. 1 (of 4) A Plain Story Simply Told Lastly, with respect to karyokinesis, although it is true that the microscope has in comparatively recent years displayed this apparently important distinction between unicellular and multicellular organisms, two considerations have here to be supplied. Darwin, and After Darwin (Vol. 1 and 3, of 3) An Exposition of the Darwinian Theory and a Discussion of Post-Darwinian Questions The comb is made of wax and is multicellular, each cell in it having six sides or as many as nature has given the bee feet. Roman Farm Management The Treatises of Cato and Varro From coenobia or social unions of these afterwards arose the lowest histones, multicellular plants and animals. Monism as Connecting Religion and Science A Man of Science It includes the phenomena of conjugation and fertilization among both unicellular and multicellular organisms. Youth: Its Education, Regimen, and Hygiene Can we conceive of an indestructible thing - be it unicellular or multicellular, alive or robotic, composed of independent individuals or acting in perfect, centrally-dictated unison? Moral Deliberations in Modern Cinema This is a formula which has now been found to apply throughout the whole range of the multicellular organisms. Darwin, and After Darwin (Vol. 1 and 3, of 3) An Exposition of the Darwinian Theory and a Discussion of Post-Darwinian Questions Every multicellular animal must first have existed as a single cell, the impregnated ovum. The Glands Regulating Personality The transit, we are told, from the unicellular to the multicellular organism cannot be explained by individualism, but implies a diminution of the competitive, an increase of the social and subordinative tendency. The Faith of the Millions (2nd series) The process of division is repeated, until the organism, from being unicellular, becomes multicellular. Darwiniana : Essays — Volume 02 The first cell-communities to be formed, which laid the early foundation of the higher multicellular body, must have consisted of homogeneous and simple amoeboid cells. The Evolution of Man — Volume 2 Like that of all other organisms, unicellular or multicellular, his development starts from the nucleus of a single cell. Darwin, and After Darwin (Vol. 1 and 3, of 3) An Exposition of the Darwinian Theory and a Discussion of Post-Darwinian Questions From one or more simple primitive unicellular forms have arisen the great multitude of multicellular forms that now exist. Sociology and Modern Social Problems In all these metazoa, or multicellular animals, the chief embryonic processes are substantially alike, although they often seem to a superficial observer to differ considerably. The Evolution of Man — Volume 1 The antennae, instead of projecting in front of the bladders, are curled under the valve, and are armed with twelve or fourteen extremely long multicellular bristles, generally arranged in pairs. Insectivorous Plants It is an interesting fact that in the plant kingdom also the simple hollow sphere is found to be an elementary form of the multicellular organism. The Evolution of Man — Volume 2 The sponges, the lowest of the multicellular animals, were represented by several orders. The Elements of Geology Briefly, it was necessary to show that ALL the multicellular animals passed through these three stages, so that our biogenetic law would enable us to recognise them as reminiscences of ancestral forms. The Evolution of Man — Volume 1 This ontogenetic process has a very great significance, and is the real starting-point of the construction of the multicellular animal body. The Evolution of Man — Volume 1 The antennae, which are united for a short distance at their bases, bear on their outer surfaces and summits numerous, long, multicellular hairs, surmounted by glands. Insectivorous Plants The Gastraea itself has originated from the simple multicellular vesicle, the Blastaea, and this in turn must have been evolved from the lowest circle of unicellular animals, to which we give the name of Protozoa. The Evolution of Man — Volume 2 I say this is very important, because our whole science of embryology now resolves itself into the problem: "How does the multicellular organism arise from the unicellular?" The Evolution of Man — Volume 1 This cell produces a cluster of cells by segmentation, and from these develops the multicellular organism, or individual of higher rank. The Evolution of Man — Volume 1 Hence, in the fertilised egg which we eat daily, the yellow yelk is already a multicellular body. The Evolution of Man — Volume 1 These are broad, flattened, and of large size; they bear on their margins multicellular hairs, surmounted by glands. Insectivorous Plants It is clear that this morula reproduces for us to-day the simple structure of the multicellular animal that succeeded the unicellular amoeboid form in the early Laurentian period. The Evolution of Man — Volume 2 The development of the multicellular organism from the ovum, and the formation of the germinal layers and the tissues, follow the same laws in man and all the higher animals. The Evolution of Man — Volume 1 Hence, although the amoeba is nothing but a simple cell, it is evidently able to accomplish all the functions of the multicellular organism. The Evolution of Man — Volume 1 Moreover, there is the fact that recent research has discovered such amoeba-like cells everywhere in the mature body of the multicellular animals. The Evolution of Man — Volume 1 In this bladder, as well as in several others, there were some unicellular Algae, and one multicellular Alga, which no doubt had lived as intruders. Insectivorous Plants The egg, in the modern physiological sense of the word, did not make its appearance until the descendants of the unicellular Protozoon had developed into multicellular animals, and these had undergone sexual differentiation. The Evolution of Man — Volume 2 When they have been fertilised, the multicellular organism is formed from them by repeated segmentation. The Evolution of Man — Volume 1 We must, therefore, turn next to the question whether there are to-day any unicellular organisms, from the features of which we may draw some approximate conclusion as to the unicellular ancestors of the multicellular organisms. The Evolution of Man — Volume 1 The ovum stands potentially for the entire organism—in other words, it has the faculty of building up out of itself the whole multicellular body. The Evolution of Man — Volume 1 The long multicellular hairs are not so quickly affected. Insectivorous Plants As we have already seen, the result of the first division of labour among the homogeneous cells of the earliest multicellular animal body was the formation of an alimentary cavity. The Evolution of Man — Volume 2 All these properties of the multicellular and highly developed animal are also found in the single animal-cell, at least in its younger stages. The Evolution of Man — Volume 1 They vary in development, and graduate, as Nitschke* states, and as I repeatedly observed, into the long multicellular hairs. Insectivorous Plants These cells are separate living beings; they are the citizens of the State which the entire multicellular organism seems to be. The Evolution of Man — Volume 1 The petioles bear many multicellular hairs, some of which near the blade are surmounted, according to Nitschke, by a few rounded cells, which appear to be rudimentary glands. Insectivorous Plants From it is developed in the same manner in all the Placentals, by repeated cleavage, a multicellular blastula. The Evolution of Man — Volume 2 The footstalks of this latter species bear multicellular hairs, which we have good reason to believe represent aborted tentacles. Insectivorous Plants On each side of the entrance from three to rarely seven long, multicellular bristles project out- FIG. Insectivorous Plants |
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