Question.

A fruit fly has four pairs of chromosomes in its cells. At meiosis, how many different combinations of maternal and paternal chromosomes are possible in the gametes?

Answer.

In gametes derived from a cell with four pairs of chromosomes there are 2^4 = 16 possible combinations of maternal and paternal chromosomes.

Question.

A cell in the basal layer of the skin contains 46 chromosomes and divides by mitosis to produce new skin cells. After ten successive divisions, how many chromosomes will the basal cell have?

Answer.

After ten successive mitotic divisions, a basal cell will still have 46 chromosomes.