Question

Which of the following sequences shows the correct life cycle for humans?

• A. diploid egg + diploid sperm --> haploid zygote --> mitosis --> haploid adult --> meiosis --> diploid gametes
• B.
  diploid egg + diploid sperm --> haploid zygote --> meiosis --> haploid adult --> mitosis --> diploid gametes
• C.
  haploid egg + haploid sperm --> diploid zygote --> mitosis --> diploid adult --> meiosis --> haploid gametes
• D.
  haploid egg + haploid sperm --> diploid zygote --> meiosis --> diploid adult --> mitosis --> haploid gametes

Answer 1

The correct option is C

haploid egg + haploid sperm --> diploid zygote --> mitosis --> diploid adult --> meiosis --> haploid gametes
Egg and sperm are haploid products of meiosis; body cells are products of mitosis. Therefore the correct sequence is: haploid egg + haploid sperm --> diploid zygote --> mitosis --> diploid adult --> meiosis --> haploid gametes.