Question

10. This question deals with material we have covered in lecture. Here is a karyotype from the fruit fly Drosophila melanogaster:

a. What is the diploid number for Drosophila melanogaster? (1 point)

b.What is the haploid number for Drosophila melanogaster? (1 point)

c.How many chromosomes will a Drosophila gamete have? (1 point)

d.After mitosis, how many pairs of chromosomes will a daughter cell

have? (2 points)

e. Sex in Drosophila is determined in the same way as it is in humans.What is the sex of this individual? (1 point)

Answer 1

a. Diploid number is represented by 2N, where N is the number of chromosomes. For Drosophila, the diploid number is 8.

b. Since the diploid number is 8, the haploid number is 4.

c. In Drosophila, there are 4 pair of homologous chromosomes, 2 large autosomes, one small autosome and a pair of sex chromosome.

d. At the end of mitosis, each daughter cell will have 32 chromosomes. This is because there are 16 chromatids at the end of metaphase stage of mitosis.

e. information not sufficient.