图2-1核苷酸的组成与结构。核苷的 5位和3位都可能与磷酸基团相连。 (嘧啶)3′-一磷酸 (嘌呤)5′-一磷酸 y (嘌呤)5′-三磷酸 CH2OH O-P 10-P O-P OH OH OH O-P=O OH OH nlpe& Pge
图2-1 核苷酸的组成与结构。核苷的 5’位和3’位都可能与磷酸基团相连
2.1染色体 2.1.1染色体一遗传物质的主要载 体 染色体在遗传上起着主要作用, 因为亲代能够将自己的遗传物质以 染色体( chromosome)的形式传 给子代,保持了物种的稳定性和连 续性。 nlpe& Pge
2.1染色体 2.1.1染色体—遗传物质的主要载 体 染色体在遗传上起着主要作用, 因为亲代能够将自己的遗传物质以 染色体（chromosome）的形式传 给子代，保持了物种的稳定性和连 续性
The nucleus of a nondividing cell (interphase) is filled with a diffuse material called Chromatin. so called because early microscopists found that it stained brightly with certain dyes. 摘自 Lehninger,3rd,p35
The nucleus of a nondividing cell (interphase) is filled with a diffuse material called Chromatin, so called because early microscopists found that it stained brightly with certain dyes. 摘自:Lehninger, 3rd, p35
Chromatin consists of Na and proteins bound tightly together and is the substance of the chromosomes which do not condense and become individually visible until the cell is ready to divide 一 °首)Hati )
Chromatin consists of DNA and proteins bound tightly together and is the substance of the chromosomes, which do not condense and become individually visible until the cell is ready to divide
Nucleolus(核仁) is a specific region of the nucleus in which dna is located Before mitosis. the double-helical DNA of the chromatin is replicated, then in the first phase of mitosis the chromatin fibers condense into discrete bodies (chromosomes), each consisting of two identical chromatids. nlpe& Pge
Nucleolus(核仁) is a specific region of the nucleus in which DNA is located. Before mitosis, the double-helical DNA of the chromatin is replicated, then in the first phase of mitosis the chromatin fibers condense into discrete bodies (chromosomes), each consisting of two identical chromatids