Question

Drosophila may be trisomic for chromosome IV and remain fertile. The gene determining the shape of bristles is in chromosome IV. The recessive allele (b) causes bent bristles, while the dominant wild type allele (b ) results in normal bristles. Predict the F1 and F2 (from all possible crosses between F1 types) results of the following cross: Trisomic, bent bristles x diploid homozygous normal bristles.

Answer 1

Answer:

I am going to give you the material so that you can be your doubt but I will not solve it because that is the basis of your learning that you react to what you are reading

In Mendel's "Experiment 1", pea plants with smooth seeds intersect with pea plants with rough seeds. (smooth seeds is the dominant feature). Mendel collected the seeds of this cross, the plants and obtained the F1-generation of plants, let them self-pollinate to form a second generation, and analyzed the seeds of the F2 generation. The results they obtained; And the ones you would predict in this experiment are:

Guide

F1-generation plants

Mendel crossed SS (smooth seeds) with ss (rough seeds.)

All the gametes of parents smooth seeds, have the allele S (dominant) and all the gametes of parents rough seeds have the allele s (recessive). All the plants of the F1 generation will affect the Ss genotype (heterozygous), and all the seeds smooth seeds.

Generation-F2 plants

Mendel let the F1-generation plants self-pollinate to form a second generation and analyzed the seeds of the resulting F2 generation.

F2 generation    

All F1 hybrid plants have the Ss genotype and all are smooth (dominant characteristic). Recessive alleles are secreted during gamete formation. As a result, one in four possible combinations in F2 generation plants will have the recessive homozygous genotype (ss).