Questions about the law of gene segregation in high school organisms.

aa aa aa aa is also a hybrid hybridization including side crossing, self-crossing, backcrossing etc.

How does a self-inbred become a hybrid??

Do two AAs have to be self-bringing?

What about the two AA animals?。。 Have you ever seen an animal self-bred?

A mating between two different individuals can be considered a hybrid, and the inbreeding should be hermaphroditic self-pollination, I remember my high school teacher explaining it, hehe. I don't know if it helps you, you can go to a special biology education forum to ask, such as the biology teaching forum, biology ** collection biology 114, which has a lot of knowledge about high school biology, which should help you.

This sentence is not true, my opinion is that your teacher's explanation is a general explanation.

There are three scenarios.

First, if a homozygous cross of a pair of genes and is present on autosomes, the shape of the offspring is dominant.

Second, it is not necessary to cross more than two pairs of genes that are homozygous, such as AAAA and AAB, and for the trait determined by the alleles of A and A, the other trait cannot be considered dominant for the relative trait.

Third, if it is inherited with sex, the traits of the offspring may not be unique, for example, in the offspring of XBXB and XBY, the female is dominant and the male is recessive, and it is impossible to judge the dominant and hidden.

First of all, the dominant form (Book 3 p4) is that the offspring show the traits of the parent, as far as the sentence you asked, the teacher's answer is correct, because hybridization refers to the mating between individuals of the same species, for example,

This should count. However, regarding the question just now, such as aabb aabb, he is not self-inbred, but if you only ask bb bb, it can be self-inbred.

There is no such sentence in the book, what my class teacher said, it seems to be correct, but the performance type of the offspring should be A, so the parent should be Aa.

Hybridization: It is the process of mating between different individuals.

Self-breeding: The same individual completes the mating process.

That's fine!

The landlord made it clear that the answer was not chosen, whether he was right or wrong.

1.In the law of segregation, when F1(dd) produces gametes, due to the separation of alleles, two equal numbers of female gametes (D, D) and two equal numbers of male gametes (D, D) are formed, and the male and female gametes are randomly combined to form 1 4dd, 1 4dd, 1 4dd, 1 4dd, and 1 4dd, and due to the masking effect of dominant genes on recessive genes, 1 4dd and 2 4dd are manifested as dominant traits, so the offspring have a trait segregation ratio of "3 1". The main reasons for its formation are allele segregation and the masking effect of dominant genes on recessive genes (complete dominance).

The segregation ratio of traits is the result of the combined effect of allele segregation and complete dominance.

2.Reasons for the ratio of traits in the law of free combination.

The law of free combination is the expansion and extension of the law of segregation in terms of "quantity", and the reason for the formation of the segregation ratio includes all the reasons for the formation of the segregation ratio in the segregation law, and there is also a reason for the free combination of non-allelic genes on non-homologous chromosomes.

3.Causes of the ratio of trait segregation in the law of linkage and exchange.

The law of separation is also the basis of the law of chain exchange, and the causes of the separation ratio include all the reasons that form the separation ratio in the law of separation. When the law of free combination f1 produces gametes, the ratio of various types of gametes is the same; However, when F1 produces gametes in the law of linkage exchange, the type and exchange rate of exchange sex mother cells are important reasons for the formation of the segregation ratio in the law of chain exchange, because some sex mother cells do not exchange and some exchange are exchanged, and the exchange includes single exchange and double exchange.