These homologous chromosomes carry different alleles of the A and B genes. How could crossing over affect the distribution of the four alleles: A, a, B, and b? A. Crossing over would always keep A and B together on the same chromosome, and keep a and b together on the same chromosome. B. Crossing over would always put A and B on different chromosomes, and always put a and b on different chromosomes. C. Crossing over would sometimes, but not always, exchange the positions of A and a, and of B and b, on homologous chromosomes. D. Crossing over would sometimes, but not always, delete one or more of the four alleles from both homologous chromosomes.

C. Crossing over would sometimes, but not always, exchange the positions of A and a, and of B and b, on homologous chromosomes.

Explanation:

Crossing over involves the exchange of chromosomal segments (and of course the respective genes on the chromosome segments) between non-sister chromatids in a tetrad during meiosis.

From the attached image, crossing over would sometimes exchange the positions of A and a, and that of B and b on the chromosome. However, this is not the case 100% of the time.

The correct option is C.

the dna of humans and mice is almost 92% similar. this similarity indicates that . mice have a tail, while humans have a tailbone. the tailbone is a structure in humans.yes it's true.

i believe the answer would be b. hope it : )