Genetics-02-03-Mendelgenetics精编.ppt

Chapter 2 Mendel’s Genetics Analysis 孟德尔式遗传分析（1） Chapter 2 孟德尔式遗传分析 第一节 孟德尔第一定律及其遗传分析 第二节 孟德尔第二定律及其遗传分析 第三节 遗传的细胞学基础 第四节 基因的作用与环境因素的相互关系 第一节 孟德尔第一定律及其遗传分析（ Mendel’s 1st Rule and his genetics analysis) 1.1 孟德尔遗传分析的方法 严格选材 精心设计 定量分析 测交验证 1.2 孟德尔实验及其分析 Why was Mendel successful? 选材（Chose a good genetic organism）: short life cycle; large progeny; can grow lots of plants in small space; access to genetic variation. 性状（Picked good traits）: easy to score; bred true. 量化结果（Quantified results）. Why Mendel Liked Peas Several variable characters with two discrete traits(许多稳定的、易于区分的性状） easy to score (yellow or green) Can control fertilization, including self-fertilization can produce pure lines（纯系） Offspring always have one of the parental traits 1.2 孟德尔实验及其分析 孟德尔分析的关键性名词概念 孟德尔实验及其分离定律的归纳 Basic Terminology 遗传性状（Hereditary traits）:一个个体从亲代传递到下一代的特性（孟德尔称为Characters, is a feature that is heritable ） 基因(gene) ： Physical and functional unit of heredity, which carries information from one generation to the next. In molecular terms, a gene is the entire DNA sequence necessary for the synthesis of a functional polypeptide or RNA molecular. 基因座(locus): Location on chromosome of gene 等位基因(allele) (Trait): is a variation of a character 显性基因(dominant gene)– a gene allele which is always expressed when it is present, regardless of whether it is homozygous or heterozygous 隐性基因(recessive gene) – a gene allele which is not expressed if it is in the heterozygous state 基因型(genotype): the genetic makeup of an organism (combination of genes in its nucleus) 表现型(phenotype): the physical appearance of an organism Basic Terminology 纯合体(homozygous) - a pair of alleles which are identical. 杂合体( heterozygous) - a single pair of alleles which are unlike each other. 真实遗传（true breeding line）- organisms that always pass the same genotype to their offspring 杂交（hybrid）- offspring resulting from crossbreeding two true breeding lines.F1 测交（testcross) Breeding a homozygous recessive with a dominant phenotype