Posted by Katrina on .
A biologist measured the amount of DNA in several single diploid cells taken from a culture. He knew that these cells could divide mitotically, but not meiotically. His data is shown below: Cell Number and DNA content in micrograms: Cell 1 (11.1 micrograms) Cell 2 (5.4 micrograms) Cell 3 (7.3 micrograms) Cell 4 ( 10.9 micrograms) Cell 5 (5.6 micrograms) Cell 6 (8.6 micrograms) Cell 7 (11.0 micrograms) Which of these cells have most likely just completed mitosis and cytokinesis? a. 1, 4, and 7 b. 3 and 6 c. 2, 3, 5, and 6 d. 2 and 5 e. No conclusion can be drawn from the data provided.
During interphase, the DNA content is doubled. After cytokinesis, the DNA content is cut in half for the daughter cells. Therefore, I would rule out cells 1, 4, and 7. After cytokinesis, the cells should have half the DNA content as the mother cell, which leaves cells 2 and 5. Cells 3, and 6 have slightly more then half, but not double the amount. I am not sure, but you can conclude that these cells are undergoing the initial parts of interphase, but they have not completed it. Therefore, answer choice d seems to be the best answer.
I am not 100% sure, but this would be my choice.