《医学遗传学》课程PPT教学课件（留学生 Medical Genetics）02 Chapter Basis of Genetics

The Second Chapter The Basis of Genetics

The Second Chapter The Basis of Genetics

Am I not destroying my enemies when I make friends of them.? -Abraham Lincoln

Am I not destroying my enemies when I make friends of them.? - Abraham Lincoln

Contents >Cellular Basis of Genetics >Molecular Basis of Genetics >Emphasis

Contents ➢Cellular Basis of Genetics ➢Molecular Basis of Genetics ➢Emphasis

Emphasis Lyon hypothesis Genetic imprinting Dynamic mutation

❖ Lyon hypothesis ❖ Genetic imprinting ❖ Dynamic mutation Emphasis

Cellular Basis of Genetics >Chromotin Chromosome >Cell Cycle >Mitosis >Meiosis

Cellular Basis of Genetics ➢Chromotin & Chromosome ➢Cell Cycle ➢Mitosis ➢Meiosis

Chromotin Chromosome Microfilament r Centriole Nucleus Ribosomes Smooth endoplasmic reticulum Mitochondrion Rough endoplasmic reticulum Golgi apparatus Lysosome Structure of Eukaryote

Structure of Eukaryote Chromotin & Chromosome

Chromotin Chromosome Euchromatin Heterochromatin Condensed Lightly Strongly Genetic Information Including Not including Replicate time Early Late Mainly Location Cytoplasm Cell nucleus Encoded protein Yes No Function With important genetic Maintenance of information chromosome structure integrity Type No Constitutive Facultative 常染色质 异染色质

Chromotin & Chromosome Euchromatin Heterochromatin Condensed Lightly Strongly Genetic Information Including Not including Replicate time Early Late Mainly Location Cytoplasm Cell nucleus Encoded protein Yes No Function With important genetic information Maintenance of chromosome structure integrity Type No Constitutive & Facultative

Chromotin Chromosome Sex chromotin X chromatin X body Barr body

Sex chromotin X chromatin X body Barr body Chromotin & Chromosome

Chromotin Chromosome Lyon hypothesis(1961) 1.Inactivation of all but one X chromosome 2.Happened at an early stage of embryogenesis 3.Happened on a random basis and maintained in all descendant cells √Dosage compensation

✓ Lyon hypothesis (1961) 1.Inactivation of all but one X chromosome 2.Happened at an early stage of embryogenesis 3.Happened on a random basis and maintained in all descendant cells ✓ Dosage compensation Chromotin & Chromosome

Chromotin Chromosome Sex chromotin Y-chromatin

Y-chromatin Chromotin & Chromosome Sex chromotin