In a species of monkey the diploid chromosome number is 48. a) the number of pai
ID: 10342 • Letter: I
Question
In a species of monkey the diploid chromosome number is 48.a) the number of pairs of homologous chromosomes in a typical somatic cell is
1. 12
2. 24
3. 48
4. 72
5. 96
b) the number of chromosomes in a single cell after mitosis would be
1. 12
2. 24
3. 48
4. 72
5. 96
c) Ignoring rare mutations, sister chromatids
1. differ in the alleles they carry for most genes
2. differ in the alleles they carry in heterozygote but not in homozygote
3. carry the same allele for each gene
4. carry the same allele for each gene and always differ from the allele on their homologous.
I put (a)-48, (b)-96 (c)-4.
Explanation / Answer
A- 24, It is asking for numbers of PAIRS of homologous chromosomes. 2n = 48 (because you are given the diploid number and somatic cells are diploid). So, 48 (chromosomes)/2 (pairs) =24 pairs of chromosomes. B- Mitosis occurs in somatic cells and results in the same number of original chromosomes as the parent cell. Here it is asking for the number of chromosomes. Since 2n = 48, 48 is your answer. C- Sister chromatin are identical, so we can automatically rule out 1 and 2. They do carry identical alleles for each gene, BUT do not ALWAYS differ from the allele on the corresponding homologous chromosome. Your answer is 3. Hope this helps.