| 单词 | sperm cell |
| 例句 | Whether the sperm cell will reach and penetrate the egg depends upon its own supply of ATP, generated in the mitochondria thickly clustered in the neck of the cell. Silent Spring 1962-09-27T00:00:00Z Because sperm cells are basically devoid of mitochondria, almost all of an embryo’s mitochondria come from the egg. 1491 2005-10-10T00:00:00Z Leeuwenhoek and Huygens were among the first people ever to see human sperm cells, a prerequisite for understanding human reproduction. Cosmos 1980-01-01T00:00:00Z Men, he said, explaining their relentless buildup of sperm cells, are far more driven by physical needs; women, by emotions. This Life: Can Gary Chapman Save Your Marriage?--This Life 2011-11-19T14:00:08Z For the triennial, his psychedelic and humorous music video “Pool Party Pilot Episode” features imprisoned sperm cells with turbans and beards. Meet Six Disrupters at the New Museum’s Triennial 2018-02-02T05:00:00Z Then she noticed the sperm cells swimming over the canvas. Admit One: Escaping the Heat in Art’s Fortress 2013-08-22T19:54:11Z “Everyone ages. Why would sperm cells be the only cells not to age as men get older?” Ladies, don’t smoke, drink or have bad thoughts while pregnant. But for men, anything goes? 2016-03-08T05:00:00Z Pollen is to plants what sperm cells are to animals. Europe was not covered by dense forest before the arrival of modern humans 2023-11-14T05:00:00Z In this process, the typical elongated sperm cells are formed from round germ cells. Possible cause of male infertility 2023-10-27T04:00:00Z It's exclusively found in sperm cells, and it is usually not active. Sperm's secret voltage switch: Scientists unlock the mystery of motility 2023-10-25T04:00:00Z Special proteins -- known as membrane transporters -- are of key importance for the mobility of sperm cells. Membrane transporter ensures mobility of sperm cells 2023-10-26T04:00:00Z In the case of sexual fertilisation, the simple chromosome sets from the egg and sperm cells come together to create a double -- diploid -- chromosome set. Proteins roll the dice to determine bee sex 2023-10-04T04:00:00Z In a common metaphor used to describe human fertilization, sperm cells are competitors racing to penetrate a passive egg. Metaphors for human fertilization are evolving, study shows 2023-10-01T04:00:00Z The pollen tube develops slowly, and the generative cell in the pollen grain divides into two haploid sperm cells by mitosis. Fundamentals of Biology 2015-01-01T00:00:00Z The sperm cells are associated with Sertoli cells that nourish and promote the development of the sperm. Concepts of Biology 2013-04-25T00:00:00Z The sperm cells cannot reach and fertilise the egg cell. Membrane transporter ensures mobility of sperm cells 2023-10-26T04:00:00Z Telfer notes that in her own work, which relies on natural precursors to human egg and sperm cells, successfully growing mature gametes remains difficult. Mice with Two Fathers? Researchers Develop Egg Cells from Male Mice 2023-03-15T04:00:00Z As Syracuse University biologist Scott Pitnick has pointed out, sperm cells are the only human cells designed to perform functions outside of the actual body. The scientist who discovered sperm was so grossed out he hoped his findings would be repressed 2023-01-02T05:00:00Z At fertilization, one of the sperm cells will finally unite its haploid nucleus with the haploid nucleus of a haploid egg cell. Fundamentals of Biology 2015-01-01T00:00:00Z The spermatids eventually reach the lumen of the tubule and grow a flagellum, becoming sperm cells. Concepts of Biology 2013-04-25T00:00:00Z If they infect sperm cells or oocytes, the precursors of eggs, their genes become part of our DNA and can be passed on to our offspring. Ancient virus may be protecting the human placenta 2022-10-27T04:00:00Z The sperm cells are mixed with “nursemaid” cells called Sertoli cells which protect the germ cells and promote their development. Biology for AP Courses 2022-06-09T00:00:00Z The “generative” cell divides and forms two sperm cells. Miller & Levine Biology 2018-01-01T00:00:00Z The only flagellated cell in humans is the sperm cell that must propel itself towards female egg cells. Anatomy and Physiology 2013-06-19T00:00:00Z The pollen tube grows from the pollen grain slowly, and the generative cell in the pollen grain divides into two sperm cells by mitosis. Concepts of Biology 2013-04-25T00:00:00Z It’s likely investigators in 2021 did a “differential extraction” DNA test for this case, which separates sperm cells from other types of cells, Professor Krane said. He Was Acquitted of a 1990 Murder. But New DNA Test Shows He Was Guilty, Officials Say. 2022-06-16T04:00:00Z The cell produced at the end of meiosis is called a spermatid and when it reaches the lumen of the tubule and grows a flagellum, it is called a sperm cell. Biology for AP Courses 2022-06-09T00:00:00Z He also noted that men were constantly making dividing sperm cells that could carry potential mutations. Merck’s COVID pill might pose risks for pregnant women 2021-12-13T05:00:00Z What special features are evident in sperm cells but not in somatic cells, and how do these specializations function? Anatomy and Physiology 2013-06-19T00:00:00Z One of the sperm cells will finally unite its haploid nucleus with the haploid nucleus of an egg cell in the process of fertilization. Concepts of Biology 2013-04-25T00:00:00Z Human cells and tissues—say, in a Petri dish—and sperm cells in a man are biologically human, but they aren't wrong to kill. I’m a philosophy professor. The argument for making abortion illegal is illogical 2021-12-04T05:00:00Z Why are the diploid zygotes produced after fertilization of sperm cells produced by spermatogenesis not similar? Biology for AP Courses 2022-06-09T00:00:00Z Researchers found various types of cells, including red blood cells and “primordial germ cells” that give rise to egg or sperm cells. New research offers glimpse into early human development 2021-11-17T05:00:00Z As is true for most cells in the body, the structure of sperm cells speaks to their function. Anatomy and Physiology 2013-06-19T00:00:00Z The two sperm cells are deposited in the embryo sac. Concepts of Biology 2013-04-25T00:00:00Z The word "spermatogenesis" — the process by which sperm cells develop — is not likely to crop up in daily conversation. Male fertility rates have plummeted. The NIH is spending millions to figure out why 2021-09-27T04:00:00Z Because Mr. Gould had been cremated, investigators collected DNA from his children, which linked Mr. Gould to the sperm cell that had been found on Ms. Kalitzke’s body, Sergeant Kadner said. Two Montana Sweethearts Were Fatally Shot in 1956. The Case Was Just Solved. 2021-06-11T04:00:00Z The lab found a sperm cell that did not belong to Bogle, officers said. DNA, forensic genealogy close 65-year-old double homicide 2021-06-09T04:00:00Z A structure called the acrosome covers most of the head of the sperm cell as a “cap” that is filled with lysosomal enzymes important for preparing sperm to participate in fertilization. Anatomy and Physiology 2013-06-19T00:00:00Z At the tip of the head of a sperm cell is a structure like a lysosome called the acrosome, which contains enzymes. Concepts of Biology 2013-04-25T00:00:00Z Dutch scientist Antonie van Leeuwenhoek made extraordinary observations of blood cells, sperm cells and bacteria with his microscopes. The Dirty Secret behind Some of the World’s Earliest Microscopes 2021-05-26T04:00:00Z That the single zygote cell formed when a microscopic sperm cell fertilizes an ovum is as much a person as you and me. Opinion | The party of McConnell, in the age of Trump, stands for nothing 2020-09-22T04:00:00Z But beyond that, white blood cells do not create sperm cells; they create more white blood cells, said Dr. Jonathon Epstein, chief scientific officer at the Perelman School of Medicine at the University of Pennsylvania. The Case of a Man With Two Sets of DNA Raises More Questions 2019-12-12T05:00:00Z ATP produced by these mitochondria will power the flagellum, which extends from the neck and the mid-piece through the tail of the sperm, enabling it to move the entire sperm cell. Anatomy and Physiology 2013-06-19T00:00:00Z The boys were at the age when their sperm cells — the vessels that would transmit their genetic material — were forming. Perspective | What men eat and drink may affect their babies’ health 2019-10-11T04:00:00Z Crucially, I learnt that this extra chromosome comes about as a result of random events during the development of the embryo, egg or sperm cells. 'There is no word for Down’s syndrome in my language' 2019-06-03T04:00:00Z Despite the decline, the average male still produces several million sperm cells each day — more than enough to produce his progeny and keep the human race going many times over. Male angst prompts a new fertility service: sperm freezing 2019-04-25T04:00:00Z It’s the DNA in sperm cells that a man passes on to his children. The Case of a Man With Two Sets of DNA Raises More Questions 2019-12-12T05:00:00Z The central strand of the flagellum, the axial filament, is formed from one centriole inside the maturing sperm cell during the final stages of spermatogenesis. Anatomy and Physiology 2013-06-19T00:00:00Z Fraternal twins, in which each of two eggs is fertilized by a different sperm cell, occur in about four of every 1000 births. Girls who share a womb with boys tend to make less money than those with twin sisters 2019-03-18T04:00:00Z It hovers around the woman when she is standing still and trails her like a little comet or a gigantic sperm cell when she is darting about. Review | ‘Gris’ is one of the most visually striking games of this or any other year 2018-12-13T05:00:00Z Perhaps the best explanation for how such trauma marks could be attached to a father’s sperm cells comes from Oliver Rando at the University of Massachusetts. Can We Really Inherit Trauma? 2018-12-10T05:00:00Z “We don’t know a cell that can make a sperm cell,” Epstein said. The Case of a Man With Two Sets of DNA Raises More Questions 2019-12-12T05:00:00Z These include supporting cells called sustentacular cells, as well as five types of developing sperm cells called germ cells. Anatomy and Physiology 2013-06-19T00:00:00Z They also secrete extracellular vesicles — and Chan showed it is these vesicles whose contents fuse with sperm cells, instilling memories of dad’s prior stress. How Dad’s stresses get passed along to offspring 2018-11-28T05:00:00Z Finally, when all the epithelial DNA is gone, the analysts add another chemical that breaks apart the sperm cell, so they can get at that prize sperm DNA. Can new technology put a dent in the rape kit backlog? 2018-11-26T05:00:00Z Chan injected sperm cells from each batch into eggs from a nonstressed female, then implanted the fertilized eggs—zygotes—into the same foster mom. How Dad's Stresses Get Passed Along to Offspring 2018-11-08T05:00:00Z “Even embryonic stem cells can’t be made into sperm cells at this point, though there are people working on it.” The Case of a Man With Two Sets of DNA Raises More Questions 2019-12-12T05:00:00Z The crucial insight behind her study was that micro-RNAs need not actually get inside sperm cells as they form. The ramifications of a new type of gene 2018-02-22T05:00:00Z The Amazon molly’s egg cells are activated to develop into an embryo by a sperm cell that degenerates without fusing with the egg’s nucleus. Girl power: life's going swimmingly for all-female fish species 2018-02-12T05:00:00Z Some 20 percent of male infertility is thought to be a result of a breakdown of immune privilege, in which sperm cells are attacked and destroyed by the body. A Private Place Where HIV, Zika and Ebola Hide 2018-01-26T05:00:00Z They also secrete extracellular vesicles—and Chan showed it is these vesicles whose contents fuse with sperm cells, instilling memories of dad’s prior stress. How Dad's Stresses Get Passed Along to Offspring 2018-11-08T05:00:00Z Heterosexual couples are increasingly likely to freeze their own eggs and sperm cells for later; fertility treatments with the poorest sperm are improving. The business of sperm banks 2017-09-14T04:00:00Z A look under the microscope showed that fibrils bind to sperm cells, immobilizing them. Protein tangles behind Alzheimer’s disease may be critical for human reproduction 2017-07-11T04:00:00Z The fish reproduces using a strategy in which a female’s egg cell develops into a baby without being fertilized by a male’s sperm cell. Girl power: life's going swimmingly for all-female fish species 2018-02-12T05:00:00Z Since sperm cells don’t mature until puberty, the immune system doesn’t recognize sperm as ‘self,’ but rather as a foreign agent. A Private Place Where HIV, Zika and Ebola Hide 2018-01-26T05:00:00Z But this nonsensical spectacle — which features what look like dancing sperm cells — is also a funny and audacious metaphor: In the gene pool of ideas, some may well prove fertile. Review | In ‘Manifesto,’ Cate Blanchett delivers 13 great performances 2017-06-08T04:00:00Z Squalius alburnoides males circumvent this problem by producing sperm cells that do not divide, and therefore contain more than one chromosome set. Somehow, This Fish Fathered a Near Clone of Itself 2017-05-26T04:00:00Z Immune cells ate up to 1.5 times more defective sperm cells when fibrils were present than when they weren’t, the team reports in eLife. Protein tangles behind Alzheimer’s disease may be critical for human reproduction 2017-07-11T04:00:00Z The fish reproduces using a strategy in which a female’s egg cell develops into a baby without being fertilized by a male’s sperm cell. Girl power: life's going swimmingly for all-female fish species 2018-02-12T05:00:00Z "It doesn't kill sperm basal motility. It is not toxic to sperm cells; they still can move," said Polina Lishko, assistant professor of molecular and cell biology from the University of California, Berkeley. Plant chemicals hope for 'alternative contraceptives' - BBC News 2017-05-15T04:00:00Z The researchers also discovered that shining a red light on the sperm cells improved their performance. Diamond dishes could boost IVF success rates 2017-04-21T04:00:00Z He and his team measured the beat of individual sperm cells' tails to try to understand the flow of fluid around the sperm. Swimming technique of sperm 'all down to simple maths' - BBC News 2017-03-19T04:00:00Z One would be to eliminate sperm hanging out for too long in the female reproductive tract, as this might trigger an unwanted immune response that would kill off all sperm cells. Protein tangles behind Alzheimer’s disease may be critical for human reproduction 2017-07-11T04:00:00Z The Amazon molly’s egg cells are activated to develop into an embryo by a sperm cell that degenerates without fusing with the egg’s nucleus. Girl power: life's going swimmingly for all-female fish species 2018-02-12T05:00:00Z Prof Lishko and her colleagues are now going to test how well these chemicals work in primates, whose sperm cells work in a similar way to humans. Plant chemicals hope for 'alternative contraceptives' - BBC News 2017-05-15T04:00:00Z The researchers coated quartz petri dishes with a superthin layer of diamond less than a micron thick, and put human sperm cells on them. Diamond dishes could boost IVF success rates 2017-04-21T04:00:00Z And these movements help selected sperm cells move forward towards their holy grail - the female egg. Swimming technique of sperm 'all down to simple maths' - BBC News 2017-03-19T04:00:00Z In the presence of fibrils, up to five times more sperm cells were devoured than in the absence of fibrils. Protein tangles behind Alzheimer’s disease may be critical for human reproduction 2017-07-11T04:00:00Z Researchers have learned cancer-predisposing mutations can emerge in sperm cells or eggs; some may not be present in the parents’ DNA. Childhood Cancer Research Looks at Genetic Origins 2016-10-03T04:00:00Z Roughly a quarter of the parthenogenote cell plus sperm cell combinations produced pups, the authors report. ‘Motherless babies!’ How to create a tabloid science headline in five easy steps 2016-09-14T04:00:00Z In a separate set of experiments, the team tested how light affects sperm cells. Diamond dishes could boost IVF success rates 2017-04-21T04:00:00Z Scientists have spent years trying to figure out why, and a new study suggests a possible explanation for the monstrous sperm cells of the humble fruit fly. Fruit fly sperm is epically long, and we may finally know why 2016-05-25T04:00:00Z The exact mechanism that causes sperm cells to attach to the pellucida is still unknown, but the peptides that comprise this layer effectively act as a glue trap for the mobile sperm. Decoy eggs used to provide birth control for mice 2016-04-27T04:00:00Z And although previous work has suggested that sperm cells can carry 'epigenetic' factors, this is the first time that such an effect has been observed with egg cells. High-fat diets raise risk of obesity in offspring 2016-03-13T05:00:00Z Other scientists raise specific concerns that mainly relate to the timing of the processes that lead to the sperm cells. Researchers claim to have made artificial mouse sperm in a dish 2016-02-24T05:00:00Z When the researchers exposed sperm cells to this wavelength, they found about twice as many Grade A cells after 30 minutes than were in control groups. Diamond dishes could boost IVF success rates 2017-04-21T04:00:00Z In a paper published Wednesday in the journal Nature, Pitnick and his fellow researchers come up with a framework for understanding the evolutionary drive behind these perplexing sperm cells. Fruit fly sperm is epically long, and we may finally know why 2016-05-25T04:00:00Z In the study, these selected sperm cells were compared to the starting population for their ability to bind to donor eggs. Decoy eggs used to provide birth control for mice 2016-04-27T04:00:00Z The idea was that if a physical trait or behaviour was observed in the offspring, it could only have been transmitted through the egg or sperm cells. High-fat diets raise risk of obesity in offspring 2016-03-13T05:00:00Z Now scientists in China report in Cell Stem Cell that they’ve figured out a new way to accomplish just that, generating the first functional sperm cells in mice. It’s Now Possible to Make Mouse Sperm in a Lab 2016-02-25T05:00:00Z That’s one conclusion from a new study, which finds that human sperm cells live longer and move more efficiently on diamond surfaces compared with traditional polystyrene petri dishes. Diamond dishes could boost IVF success rates 2017-04-21T04:00:00Z Across most mammal species, sperm cells need the environment of the female reproductive tract before they become effective—a process known as capacitation. See the First-Ever IVF Puppies 2015-12-09T05:00:00Z However, the sperm cell changes he recorded are linked to the genes known for appetite control and brain development. Man's weight 'affects sperm cells' - BBC News 2015-12-03T05:00:00Z The health effects of a bad diet can carry over to offspring through eggs and sperm cells without DNA mutations, researchers have found. High-fat diets raise risk of obesity in offspring 2016-03-13T05:00:00Z The scientists then recreated the chemical environment that sperm cells need to grow, including early development factors and sex hormones including testosterone, follicle stimulating hormone and a growth factor from the pituitary gland. It’s Now Possible to Make Mouse Sperm in a Lab 2016-02-25T05:00:00Z Then they did the same thing for sperm cells taken from the same sample but placed on traditional polystyrene petri dishes. Diamond dishes could boost IVF success rates 2017-04-21T04:00:00Z A sperm cell delivers DNA to an egg, of course. Parents May Pass Down More Than Just Genes, Study Suggests 2015-12-03T05:00:00Z The sperm cells of lean and obese men possess different epigenetic marks, maybe changing the behaviour of genes. Man's weight 'affects sperm cells' - BBC News 2015-12-03T05:00:00Z They include editing immature sperm cells to allow infertile men to father children. Too early to use gene editing in embryos: scientist 2015-12-02T05:00:00Z This is not metaphoric sperm: This very stationary tree produces a wriggling, swimming sperm cell capable of fertilizing female ginkgo ovules. The Female Ginkgo Tree’s Acrid Smell of Success 2015-10-29T04:00:00Z After an hour, the diamond-coated petri dishes contained 300% more Grade A sperm cells than did the polystyrene dishes, the team reports in the Annals of Translational Medicine. Diamond dishes could boost IVF success rates 2017-04-21T04:00:00Z These retroviruses initially infected a human egg or sperm cell and entrenched themselves in chromosomes, allowing them to spread from one generation to the next. Is an ancient virus responsible for some cases of Lou Gehrig’s disease? 2015-09-30T04:00:00Z That way, when an egg and sperm cell merge, the right number of chromosomes combine to make healthy offspring. The Verge Review of Animals: the all-female whiptail lizard 2015-07-19T04:00:00Z The sperm cells resemble those of modern crayfish worms, leechlike animals that cling symbiotically to freshwater organisms. 50-Million-Year-Old Fossilized Sperm in Antarctica 2015-07-17T04:00:00Z “It would be of great interest to see if these annelid sperm cells preserved in the cocoons also contain subcellular structures,” says Archer, who also did not participate in the research. 50-Million-Year-Old Worm Sperm Found in Antarctica 2015-07-14T04:00:00Z Because of their delicate nature, sperm cells are very rarely found in fossils. Oldest animal sperm found inside fossilized worm cocoon 2015-07-14T04:00:00Z Even more surprisingly, the sperm cells appeared strangely similar to those of present-day, leechlike worms called Branchiobdellids. Oldest animal sperm unearthed in Antarctica 2015-07-14T04:00:00Z The greater the number of RNA elements missing from the sperm cell, the lower the likelihood of conception, the researchers said. Genetic Test May Help Spot Male Fertility Problems 2015-07-08T04:00:00Z At trial, a medical expert argued the sperm cell found in the diaper couldn’t have been Cole’s because he’d previously had a vasectomy more than a decade prior to the event. Court tosses out Peoria man’s sexual assault conviction 2015-05-20T04:00:00Z A 50-million-year-old fossil of a sperm cell recently found in Antarctica. 50-Million-Year-Old Worm Sperm Found in Antarctica 2015-07-14T04:00:00Z Cartoons brighten the lab walls: A sperm cell wears a baseball hat. ‘Lean in. But freeze first.’ The fertility business targets women’s fears. 2015-03-06T05:00:00Z Called MENT, the device releases a synthetic steroid that resembles testosterone, which affects sperm cell development. The Future of Male Birth Control 2015-02-26T05:00:00Z Recent research has shown that sperm cells harbor a surprisingly rich amount of RNA, which appears to play a distinct role in fertilization and early development of the embryo, the study authors said. Genetic Test May Help Spot Male Fertility Problems 2015-07-08T04:00:00Z The men are collecting their own sperm samples, as a first step in analyzing the potency of their sperm cells for making offspring. Infertility Struggles? It’s Not Always a Woman's Issue 2015-02-10T05:00:00Z While sifting, Mörs found fossil worm cocoons, and a closer look using an electron microscope revealed the presence of numerous trapped sperm cells. 50-Million-Year-Old Worm Sperm Found in Antarctica 2015-07-14T04:00:00Z She would extract DNA from the developing sperm cells of mice, send it for analysis and then fire up a package called GeneSpring to study the results. Programming tools: Adventures with R 2014-12-28T05:00:00Z Sperm extracted from the experimental group of rats showed that the majority of their sperm cells were dead, whereas most of the control group’s sperm cells were alive. Boxer Rebellion: A Pocketed Cellphone May Be Behind Your Infertility Unfortunately, this doesn’t always work — sometimes the sperm cells are just too quick, and things can go terribly wrong. Scientists discover 'killer' roundworm sperm 2014-07-29T04:00:00Z Of the hundreds of millions of sperm cells that begin the journey up the oviducts, only a few ever reach their destination. Sperm swim upstream 'in a shoal' 2014-05-27T04:00:00Z They are shrimp-like animals typically around 1 millimetre in length, but their sperm cells are disproportionately long — up to 1 centimetre. Giant sperm found in crustacean fossils 2014-05-13T04:00:00Z They are shrimp-like animals typically around 1 millimeter in length, but their sperm cells are disproportionately long — up to 1 centimeter. Giant Sperm Found in Crustacean Fossils 2014-05-14T04:00:00Z Seventeen million years later, the fossilized tissue contains the preserved internal organs, including the sexual organs — and almost entirely preserved sperm cells, which would have contained the ostracod’s DNA. 17-million-year-old giant sperm discovered — and it was preserved in a very strange way 2014-05-14T04:00:00Z But some aspects of these observations aren’t altogether novel, given that there are other animal species where sperm cells move through the body cavity before fertilizing egg cells. Scientists discover 'killer' roundworm sperm 2014-07-29T04:00:00Z He and his team were looking for a counterpart to a protein called Izumo1, discovered in 2005 on the surface of sperm cells. Uniter of Sperm and Egg Is Found 2014-04-18T11:00:00Z A long, long time ago a virus infected a sperm cell or oocyte of one of our ancestors. Genetic Chimeras: Are You Your Own Twin? 2014-04-13T09:41:16Z The researchers say that any increased risk due solely to paternal age is most likely a result of the accumulation of genetic mutations in sperm cells. Mental Illness Risk Higher for Children of Older Parents, Study Finds 2014-02-26T21:00:02Z Male mice in one group were fed a folate-deficient diet from womb to adulthood, because sperm cells start to form when pups are still in utero. Father’s diet may affect offspring’s development, study of mice suggests 2013-12-14T21:52:45Z Some institutions follow this principle strictly, and require written, informed consent from the deceased before they will retrieve sperm cells. Making Babies After Death: It's Possible, But is it Ethical? 2013-06-12T22:45:00.297Z The trick is to look not just at the sperm cells but inside them to get a sense of how their DNA is packaged—and to do that without destroying them in the process. Fertility Breakthroughs Are Bringing New Life into the World 2013-05-31T23:50:30Z Each time sperm cells divide new mutations can be introduced into a person's genome. Older fathers more likely to have autistic grandchildren 2013-03-20T20:04:05Z There must be a high density of sperm cells in the sample. Green Blog: The Panda Vigil 2012-09-19T12:04:41Z Using their chip-based, holographic imaging method, the researchers tracked the swimming patterns of some 1500 human sperm cells over several hours. Video: As the Sperm Swims 2012-09-17T20:00:00Z And here’s a link to a detailed diagram of a sperm cell from a liverwort, a close relative of mosses. How Mosses Have Sex in Spite of Their Swimming-Challenged Sperm 2012-07-28T11:45:00.203Z The current method of sequencing destroys the sperm cell subject. Sequencing of Single Sperm Could Reveal New Infertility Causes 2012-07-19T17:45:00.217Z The researchers said that while the mechanism behind the link to older fathers and grandfathers is not clear, it may be explained by mutations occurring in sperm cells over time. Older fathers more likely to have autistic grandchildren 2013-03-20T20:04:05Z When it comes to reproductive outcomes, older men are actually disadvantaged compared with older women, due to the high rate of sperm cell division. Father Time: Children with Older Dads at Greater Risk for Mental Illness 2011-08-29T12:15:00.260Z Reporting today in the Proceedings of the National Academy of Sciences, the researchers found that about 90% of sperm cells swim along a slightly curved axis. Video: As the Sperm Swims 2012-09-17T20:00:00Z By finding how methods of handling affect the sperm cells, one can sometimes improve the procedures to avoid harmful effects. Preservation of Bull Semen at Sub-Zero Temperatures 2011-08-13T02:00:22.680Z Japanese scientists successfully restored fertility in sterile mice using sperm cells that were originated in the lab, reports a new study in the journal Cell. Scientists Restore Fertility in Mice With Lab-Made Sperm 2011-08-06T05:19:39Z Japanese researchers successfully implanted early sperm cells, made from the stem cells, into infertile mice. Stem cell sperm 'fertility hope' 2011-08-04T16:26:45Z Once boys hit puberty, their sperm cells divide every 16 days. Father Time: Children with Older Dads at Greater Risk for Mental Illness 2011-08-29T12:15:00.260Z The constant unzipping and replication of DNA required to produce millions of sperm cells each day means there are many opportunities for the biological assembly line to be broken. Chernobyl's fall-out 2011-07-26T00:12:32Z The key to a pill for men may lie in vitamin A, which is necessary for the growth of sperm cells. Birth Control Pills for Men: Would You Use It? 2011-06-15T17:02:59Z Samples are delivered from the sperm bank to the aptly-named Stork Klinik, across Copenhagen, in the industry's latest gimmick; a bicycle in the shape of a single sperm cell. Dads anonymous 2011-05-19T23:55:37Z The scientists were able to coax stem cells into early sperm cells Fertility experts are hailing a mouse study in which working sperm cells were created from embryonic stem cells in mice as "hugely exciting". Stem cell sperm 'fertility hope' 2011-08-04T16:26:45Z "By the time a man is 40, his sperm cells have undergone 660 cell divisions, and 800 cell divisions by age 50," he says. Father Time: Children with Older Dads at Greater Risk for Mental Illness 2011-08-29T12:15:00.260Z Pregnancy also requires the fertilization of the ovule with a sperm cell. Superfetation: Pregnant while already pregnant 2011-04-27T13:15:05.213Z The latest studies, led by independent teams in Germany and the United States who agreed to publish their findings simultaneously, show that progesterone activates a molecular channel called CatSper, which floods sperm cells with calcium. Female Hormone Could Be Key to Male Contraceptive 2011-03-16T22:45:00.303Z Up to 80 percent of cases are thought to be due to the effects of oxidative stress on sperm cells, lowering both their numbers and their quality. Antioxidants may improve male fertility 2011-01-20T20:15:44Z One in 20 men have poor fertility and in many cases this is thought to occur when highly reactive particles called free radicals which circulate in the body, cause damage to sperm cells. Antioxidants may help men with fertility problems, study reveals 2011-01-19T06:00:01Z Egg cell, the large, non-motile reproductive cell, with which a sperm cell fuses. A Guide for the Study of Animals 2011-01-18T03:00:14.913Z It happens when there is fertilization of an ovule by a sperm cell while a conceptus is already present in the womb. Superfetation: Pregnant while already pregnant 2011-04-27T13:15:05.213Z In one, a team turned immature sperm cells into pancreatic tissue, while another team turned embryonic stem cells into complex layers of intestinal tissue. Stem cells used to make pancreas, gut cells 2010-12-13T05:17:00Z The test works by detecting an antigen found on the surface of the head of a sperm cell known as SP-10, which Herr and his colleagues discovered. Test allows men to check their sperm count at home 2010-02-25T18:24:00Z The concentration of protons inside the sperm cell is 1,000 times higher than outside. 2010-02-05T00:08:00Z In nature these two centres of positive concentration are introduced into the protoplasm of the cell by fecundation—that is, by the entrance of the centrosomes of the sperm cell. The Mechanism of Life These sacs contain the developing sperm cells or eggs, and are with very few exceptions universal in the group. Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 7 "Cerargyrite" to "Charing Cross" The two maturation divisions of the sperm cell. A Critique of the Theory of Evolution The egg cell and the sperm cell fuse together. The Meaning of Evolution In physical science we know the vital force exists which builds the germ and sperm cells, but we do not comprehend it. The Christian Foundation, Or, Scientific and Religious Journal, Volume 1, January, 1880 Many biologists doubt whether we have any proof that environmental influence can weaken the sperm cells of the male in such a way that the offspring are thereby weakened. The Good Housekeeping Marriage Book When ripe, if brought into water, the antheridium bursts at the top into a number of irregular lobes that curl back and allow the mass of sperm cells to escape. Elements of Structural and Systematic Botany For High Schools and Elementary College Courses It is essentially the same in the egg and in the sperm cells. A Critique of the Theory of Evolution These little bodies, carried by the blood, were taken up by the egg cells or sperm cells, and the latter cells determined the future development. The Meaning of Evolution The female, whether bird or beast, forms a true egg which must be fertilized by the male sperm cell before the offspring can develop. The Dollar Hen Several of these sperm cells start, but only one enters the ovum and is absorbed into it. Woman and the New Race The former divides repeatedly, until a mass of about thirty-two sperm cells is formed, each giving rise to a large spirally-coiled spermatozoid. Elements of Structural and Systematic Botany For High Schools and Elementary College Courses But among the males, the odd chromosome, also known as the X-chromosome, can perforce go only into half of the sperm cells, leaving the others without it. The Glands Regulating Personality In the formation of the sperm cell set free by the male a similar throwing away of one-half the characters has taken place. The Meaning of Evolution By infertile eggs is meant eggs in which the sperm cell has never united with the ovum. The Dollar Hen It is the moment of fecundation, or the union of the germ and sperm cells, which marks the beginning of pregnancy. The Four Epochs of Woman's Life; a study in hygiene When ripe, the mass of sperm cells crowds so upon the outer cells as to render them almost invisible, and as they ripen they separate by a partial dissolving of the division walls. Elements of Structural and Systematic Botany For High Schools and Elementary College Courses Its secretion has been shown to be necessary to the vitality of the sperm cells. The Glands Regulating Personality In this milt are the sperm cells of the male, each consisting of a rounded head and a very slender body. The Meaning of Evolution No sooner have the eggs, fertilized by the sperm cells, reached the water than the mucous at once begins to swell. The Meaning of Evolution Conception, or impregnation, is the union of the germ and sperm cell which results in a new being. The Four Epochs of Woman's Life; a study in hygiene The upper part consists of a single layer of large chlorophyll-bearing cells, enclosing a mass of very small, nearly cubical, colorless, sperm cells each of which contains an excessively small spermatozoid. Elements of Structural and Systematic Botany For High Schools and Elementary College Courses After lying a few moments in the water, the wall of each sperm cell becomes completely dissolved, and the spermatozoids are released, and swim rapidly away with a twisting movement. Elements of Structural and Systematic Botany For High Schools and Elementary College Courses There are doubtless a thousand sperm cells that went to utter waste for one which found an egg to fertilize. The Meaning of Evolution Conception, or impregnation, is the union of the germ and the sperm cell, the result of which is a new being. The Four Epochs of Woman's Life; a study in hygiene |
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