3. Energy & Cell Processes

Which of the following occurs during S phase?(A) condensation of the chromosomes(B) replication of the DNA(C) separation of sister chromatids(D) spindle formation

Cell A has half as much DNA as cells B, C, and D in a mitotically active tissue. Cell A is most likely ina. G1.b. G2.c. prophase.d. metaphase.

A biochemist measured the amount of DNA in cells growing in the laboratory and found that the quantity of DNA in a cell doubleda. between prophase and anaphase of mitosis.b. between the G1 and G2 phases of the cell cycle.c. during the M phase of the cell cycle.d. between prophase I and prophase II of meiosis.

A particular cell type spends 4 hours in G1 phase, 2 hours in S phase, 2 hours in G2 phase, and 30 minutes in M phase. If a pulse–chase experiment were performed with radioactive thymidine on an asynchronous culture of such cells, what percentage of mitotic cells would be radiolabeled 9 hours after the pulse?a. 0 percentb. 50 percentc. 75 percentd. 100 percent

If a cell at G1 contains four picograms of DNA, how many picograms of DNA will it contain at the end of the S phase of the cell cycle?a. 0;b. 2;c. 4;d. 8