Drosophila melanogaster, the fruit fly, has a 2n chromosome number of 8. Assume that you are microscopically examining the mitotic and meiotic cells of this organism
You note that in the female, two chromosomal pairs are metacentric and two pairs are acrocentric.
(a) Draw the chromosomal configurations as you would expect to see them at the stages listed:
mitotic metaphase first polar body (metaphase)
primary oocyte (metaphase) ootid (G1)
secondary oocyte (metaphase)
(b) Given that the previously mentioned cells are from individuals heterozygous for two independently segregating, autosomal loci, plum eyes and curled wings, place appropriate symbols (of your designation) on chromosomes in the drawings you made for part (a). Assume no crossing over, and there may be more than one correct answer in some cases.
(c) Assuming that a somatic G2 nucleus from the individuals mentioned above contains about 8.0 picograms of DNA, how much nuclear DNA would you expect in each of the cells mentioned in part (a)?
(a, b)
(c) 8, 8, 4, 4, 2
You might also like to view...
Where are chondrocytes located?
a. woven through collagen b. in muscle fibroblasts c. in cartilage lacunae d. within blood plasma
In humans, germ cells are located in the
A. ovaries and bone marrow. B. ovaries. C. bone marrow. D. testes and ovaries. E. testes.
Which phylum of vascular, seed-bearing plants comprises about 80% of all living gymnosperms?
a. Anthophyta b. Coniferophyta c. Cycadophyta d. Ginkgophyta
________ is the evolutionary history of a species or group of related species
a. Cladistics b. Phenetics c. Phylogeny d. Cladogram