But for the remaining .1%, one person might have an adenine where another person has a guanine.

但对于剩下的0.1%，一个人可能有腺嘌呤而另一个人有鸟嘌呤。

SIRT1 depends on a molecule called NAD (Nicotinamide adenine dinucleotide), and NAD, in turn, depends on the substance called NMN.

SIRT1的合成取决于一种叫NAD（辅酶）的分子，而NAD的合成则取决于一种叫NMN的物质。

The rules of base pairing dictate that adenine always pairs with thymine, and cytosine always pairs with guanine.

碱基配对规则规定腺嘌呤总是与胸腺嘧啶配对，胞嘧啶总是与鸟嘌呤配对。

DNA is made of four organic bases: adenine, guanine, cytosine, and thymine, or A, G, C, and T.

DNA 由四种有机碱基组成：腺嘌呤、鸟嘌呤、胞嘧啶和胸腺嘧啶，即 A、G、C 和 T。

See, DNA is made up of four different building blocks called " bases" : adenine, cytosine, guanine, and thymine.

看，DNA 由四种称为“碱基”的不同构件组成：腺嘌呤、胞嘧啶、鸟嘌呤和胸腺嘧啶。

It was known that DNA had four chemical components - called adenine, guanine, cytosine, and thiamine - and that these paired up in particular ways.

当时已经知道，DNA含有4种化学成分——腺嘌呤、鸟嘌呤、胞嘧啶和胸腺嘧啶——这4种成分总是以特殊的配对方式排列。

For example, you convert formaldehyde into a compound called formate, which helps make the nucleic acids adenine and guanine — two of the four building blocks of DNA.

举个例子，你把甲醛转化成一种叫做甲酸的化合物，它能帮助生成核酸腺嘌呤和鸟嘌呤——这是 DNA 的四个组成部分中的两个。

The bases - the letters of the genetic alphabet - consist of the four nucleotides mentioned a page or two back: adenine, thiamine, guanine, and cytosine.

碱基——基因子母表中的字母——由前面我们提到的腺嘌呤、鸟嘌呤、胞嘧吟和胸腺嘧啶4种核苷酸组成。

All living organisms are built from DNA. It is made from four blocks of chemicals called adenine (A), cytosine (C), guanine (G) and thymine (T).

所有生物体都是由 DNA 构成的。它由四种化学物质组成，称为腺嘌呤 (A)、胞嘧啶 (C)、鸟嘌呤 (G) 和胸腺嘧啶 (T)。

In the first stage, the energized electrons from chlorophyll are used to create two vital energy--carrying molecules: ATP (adenosine triphosphate) and NADPH (nicotinamide adenine dinucleotide phosphate).

在第一阶段，来自叶绿素的激发电子被用来产生两种携带生命能量的分子：ATP（三磷酸腺苷）和NADPH（烟酰胺腺嘌呤二核苷酸磷酸）。

Nucleotides of DNA are made out of a sugar deoxyribose, a phosphate, and one of the four nuclear bases: adenine, cytosine, guanine, and thymine or A, C, G, T for short.

DNA的核苷酸由脱氧核糖、磷酸以及四个核碱基之一组成，分别是腺嘌呤、胞嘧啶、鸟嘌呤与胸腺嘧啶，或简称A、C、G、T。

This attaches methyl groups (a carbon atom and three hydrogens) to either adenine or cytosine, two of the four chemical bases that form the alphabet of DNA, depending on the gene involved.

该作用可以让甲基（由一个碳原子和三个氢原子组成）附着于腺嘌呤或胞嘧啶上——组成DNA序列的四种主化学成分中的两种，到底附着的是哪种取决于涉及到的基因种类。

It's composed of long strands of nucleotides, each made up of a sugar molecule, a phosphate group, and one of four nitrogen bases: adenine (A), thymine (T), cytosine (C), or guanine (G).

它由长链核苷酸组成，每条核苷酸链由一个糖分子、一个磷酸基团和四个氮碱基之一组成：腺嘌呤 (A)、胸腺嘧啶 (T)、胞嘧啶 (C) 或鸟嘌呤 (G)。