《医学遗传学 Medical Genetics》课程授课教案（PPT课件讲稿）第十讲 人类染色体 human chromosome

Medical Genetics 09人类染色体 human chromosome

Medical Genetics 09 人类染色体 human chromosome

Medical Genetics a chromosome is the visible state of genetic material during a phase of the division of the cell (metaphase)

Medical Genetics A chromosome is the visible state of genetic material during a phase of the division of the cell (metaphase)

Medical Genetics Humans have 23 pairs of chromosomes, which makes the diploid number 46. The diploid number is the number of chromosomes of a normal cell

Medical Genetics Humans have 23 pairs of chromosomes, which makes the diploid number 46. The diploid number is the number of chromosomes of a normal cell

Medical Genetics The haploid number is the number of chromosomes in a gamete. Usually, the diploid number is twice the haploid number

Medical Genetics The haploid number is the number of chromosomes in a gamete. Usually, the diploid number is twice the haploid number

Medical Genetics The number of chromosomes varies depending on the species

Medical Genetics The number of chromosomes varies depending on the species

Medical Genetics 1. chromatin Chromatin is that portion of the cell nucleus which contains all of the DNA of the nucleus in animal cells.(A small amount of special dNa is also found in the mitochondria of the cell cytoplasm outside of the cell nucleus

Medical Genetics 1. chromatin Chromatin is that portion of the cell nucleus which contains all of the DNA of the nucleus in animal cells. (A small amount of special DNA is also found in the mitochondria of the cell cytoplasm outside of the cell nucleus.)

Medical Genetics Pore Nuclear Envelope Euchromatin M Hetero- chromatin aa围 print pars brose Nucleo organiz endoplasmic center

Medical Genetics

Medical Genetics A heterchromatin and euchromatin The degree of condensation of the nuclear dna is variable Strongly condensed DNA is called heterochromatin, ess condensed one euchromatin Heterochromatin is stained more intense than euchromatin by certain nuclear dyes

Medical Genetics A. heterchromatin and euchromatin The degree of condensation of the nuclear DNA is variable. Strongly condensed DNA is called heterochromatin, Less condensed one euchromatin. Heterochromatin is stained more intense than euchromatin by certain nuclear dyes

Medical Genetics Heterochromatin is the condensed form of chromatin organization It is seen as dense patches of chromatin

Medical Genetics Heterochromatin is the condensed form of chromatin organization. It is seen as dense patches of chromatin

Medical Genetics Abundant heterochromatin is seen in resting or reserve cells such as small lymphocytes(memory cells) waiting for exposure to a foreign antigen Heterochromatin is considered transcriptionally inactive

Medical Genetics Abundant heterochromatin is seen in resting, or reserve cells such as small lymphocytes (memory cells) waiting for exposure to a foreign antigen. Heterochromatin is considered transcriptionally inactive