Question

2. Assume that crossing over does not occur in the region of each chromosome that is associated with the centromere. You have 46 centromeric regions in each cell, 23 that are copies of the DNA in your mother’s egg and 23 that are copies of the DNA father’s sperm. Show your work for A,B,C a. For any given gamete, what is the probability that all the centromeric regions (chromosomes) will be copies of the same ones that you received from your mother? b. It has been estimated that the average person is heterozygous for at least 2,000 protein forming genes. How many different kinds of gametes is it theoretically possible for each person to produce? c. Considering the maternal and paternal origin of the centromeric regions alone, how many different kinds of gametes can you produce?

Answer 1

Answer:

See below

Explanation:

A. centromeric regions from mother in one cell: 23

total number of centromeric regions in one cell: 46

for every centromeric region that is inherited by the gamete, there is a 0.5 probability that it is from the mother. Hence, if all are from the mother:

0.5 ^ 23 = 1.19 x 10^(-7)

B. Heterozygous for 2000 genes means 4000 possible alleles.

2 ^ 4000 = 1.3 x 10^(1204)

C. 2 ^ 46 = 7.03 x 10^(13)