genetics help?plz?

Question

Alleles of a gene are found at ______chromosomes.
A)the same locus on heterologous
B)the same locus on homologous
C)different loci on heterologous
D) the same locus on homologous mitochondrial
E) different loci on homologous

Select the letter and answer why?And plz don't give any links.Just write here what you have to because i don't have much time

Answer 1

B

locus = position

homologous = "same"

Alleles/genes occur in specific sequences, and only on certain chromosomes. So in humans, what genes occur on chromosome #1 would be different than the genes on chromosome #5 (#1 and #5 are heterologous). And what genes are X distance from a centromere would be different that that Z distance. Otherwise, when crossing over occurs, cells could be missing complete sets of information.

So genes have to occur at the same location on the same "set" of chromosomes.