Question

A zoologist examined an intestine cell from a crayfish and counted $200$ chromosomes, each consisting of $2$ chromatids, at prophase I of mitosis. What would he except to see in each of the four cells at telophase II of meiosis if he looked in the crayfish ovary?

• A. $50$ chromosomes, each consisting of $2$ chromatids
• B. $50$ chromosomes, each consisting of $1$ chromatid
• C. $100$ chromosomes, each consisting of $2$ chromatids
• D. $100$ chromosomes, each consisting of $1$ chromatids

Answer 1

Answer: (D)

$100$ chromosomes, each consisting of $1$ chromatids

• Total no. of chromosomes are 200 meaning 100 pairs.
  
• these 100 pairs separate during meiosis 1 after crossing over.
  
• At the start of meiosis 2, each cell has 100 chromosomes with 2 chromatids.
  
• At Telophase 2 of meiosis 2, each cell with has 100 chromosomes with one chromatid.
  

So, the correct option is '100

100 chromosomes, each consisting of 11

chromatids'