生物必修二知识点（Biology requires two knowledge points）.doc

生物必修二知识点（Biology requires two knowledge points） Mendel discovered the laws of biological inheritance by analyzing the results of pea hybridization experiments. 2. Mendel in hybridization experiments, remove all stamens of immature flowers, this is called castration. 3. the different manifestations of the same character of a species are called relative traits. 4., Mendel showed the characters of F1, called dominant characters, and the characters that did not appear were called recessive characters. In hybrid offspring, both dominant and recessive traits occur at the same time, which is called trait segregation. 5. Mendel proposed the following hypothesis about the cause of the separation: (1) biological traits are determined by genetic factors, which determine the appearance traits as dominant factor, the use of capital letters, decided to recessive character recessive factor in lowercase letters. (2) the genetic factors in somatic cells are paired, and the genetic factors that constitute the same individual are called homozygotes, and the genetic factors that make up different individuals are called heterozygotes. (3) when living organisms form gametes, gametes, paired genetic factors are separated from one another into different gametes, each of which contains only one of each pair of genetic factors. (4) when fertilized, the binding of the male and female gametes is random. 6. test cross is to let F1 and recessive homozygote cross. 7. Mendels first law, also called the separation law. In biological cells, there are pairs of genetic factor the same trait, dont mix, during the formation of gametes, pairs of genetic factor separation, genetic factor separated into different gametes respectively, with gametes offspring. Chapter 1, verse second 1. Mendel with pure yellow and pure green pea round marrowfat as hybrid parents, either orthogonal or reverse, produce seeds (F1) are yellow pellets. This shows that the yellow and green round is a dominant trait is recessive an