Question

cell a has 5 picograms of dna. cell b has 10 picograms of dna. both cells are from the same organism. which of the following is the best description of the cell - cycle stage of each cell?
cell a is in g1 phase; cell b is in g2 phase
cell a is in g1 phase; cell b is in s phase
cell a is in g2 phase; cell b is between g1 and s phase
cell a is in prophase of mitosis; cell b is in metaphase of mitosis

Explanation:

In the cell - cycle, G1 phase cells have the diploid amount of DNA. During the S phase, DNA replication occurs and the amount of DNA doubles. G2 phase cells have twice the amount of DNA as G1 phase cells. Cell A has 5 picograms of DNA and Cell B has 10 picograms. Since the amount of DNA in Cell B is double that of Cell A, Cell A is likely in G1 phase (before DNA replication) and Cell B is likely in G2 phase (after DNA replication).

Answer:

Cell A is in G1 phase; Cell B is in G2 phase