Question

Mitosis and meiosis are both integral processes in gene transmission. However, the processes, while similar, have distinct differences. For these processes:

a)Explain how alleles are transmitted differently in mitosis versus meiosis and why both processes are necessary.

Genetic variation in offspring is the result of several processes.  

b) Explain these processes at the chromosomal level.

Answer 1

A. Mitosis transmit all alleles equally to all cells. There is no diffrence in alleles transmisiion when mitosis take place. So all cells should be identical. All cells work for body function so it should be identical gene.

But in meiosis due to crossing over between alleles the cells are not identical. Meiosis generally occurs in germ cells. The germ cells should show the difference between. Eg. same parent cross with each other produce a offspring. For second child between them will be identical from 1st child if there is no crossing over between alleles. 1st child gets some dominant gene 2nd child may get recessive allele. This shows the difference between offspring

B. In mitosis 2n in one cell is conveted to 2n chromosome to 2 cells. All chromosomes are same in every generation.

In meiosis in prophase I in panchytene crossing over occur between alleles. This will exchange the alleles between the chromosome. The 2n is converted to n to germ cells.