Final answer:
In humans, somatic cells like brain and skin cells contain 46 chromosomes, while gametes like sperm and eggs contain 23 chromosomes. A fertilized egg, or zygote, contains 46 chromosomes, being diploid.
Step-by-step explanation:
The question asks about the chromosome content in different human cell types. Here's a concise answer to each part of the question:
- (a) A brain cell is a type of somatic cell and contains 46 chromosomes (23 pairs).
- (b) A sperm in the testes, which is a gamete, has 23 chromosomes, being haploid.
- (c) An egg just produced by the ovary, also a gamete, contains 23 chromosomes.
- (d) A skin cell, another somatic cell, contains 46 chromosomes.
- (e) A fertilized egg, or zygote, contains 46 chromosomes, as it is formed by the fusion of a sperm and an egg, each contributing 23 chromosomes.
In summary, somatic cells like brain and skin cells are diploid with 46 chromosomes, while gametes like sperm and eggs are haploid with 23 chromosomes. Upon fertilization, the resulting zygote is diploid with 46 chromosomes.