Question

A Rhesus monkey has 42 chromosomes. How many chromosomes would be present in the zygote of this monkey?
(a) 42
(b) 21
(c) 84
(d) None of the above

Answer 1

Hint: The number of chromosomes in a Rhesus monkey is 42. The zygote is formed by the fusion of one gamete of both the parents. The number of chromosomes in each gamete is equal to 21.

Complete step by step answer:
A Rhesus monkey with 42 chromosomes would be present in the zygote of this monkey.
A fertilized egg cell that is formed by the union of a female gamete and a male gamete. The gametes are the only cell that does not contain a pair of chromosomes; it only carries just one copy of each chromosome (21 chromosomes in each gamete). The zygote is composed of genes from two parents and thus it is said to be diploid in nature containing two sets of chromosomes, which means it contains two copies of each chromosome. male gamete + female gamete = zygote
(21 chromosomes) + (21 chromosomes) = (42 chromosomes). Thus, based on the above explanation the monkey would have 42 chromosomes in its zygote.
So, the correct answer is,'42'.

Note:
- A fertilized egg cell that is formed by the union of a female gamete and a male gamete.
- The zygote is composed of genes from two parents and thus it is said to be diploid in nature.
- In humans, each of the gametes contains 23 chromosomes.