Question

3. Scientists who study the cell cycle use fluorescent dyes and lasers that enable them to measure the DNA content of individual cells. They can count the number of cells with 2N and 4N DNA content, as well as in between 2N and 4N (greater than 2N, but not quite 4N yet). a. In what phase(s) of the cell cycle will cells have 2N DNA content

Answer 1

Answer:

G1 phase

Explanation:

The cell cycle is divided into 2 major phases

1. The interphase

2. The m phase

The interphase, in chronological order, is further subdivided into

• G1 phase
• S phase
• G2 phase

Cells grow and develop at the G1 phase while the G2 phase is characterized by protein synthesis in addition to continued growth.

The DNA of a cell in interphase is doubled at the S phase. This means that if a cell has a 2N amount of DNA at the beginning of the S phase, the amount of DNA at the end would have become 4N. This amount of DNA is shared into 2 daughter cells in equal amounts during mitosis or the m phase, meaning that each daughter cell would have a 2N amount of DNA before entering the interphase.

Hence, cells will have 2N DNA content in a period that spans through the end of the m phase of the cell cycle to the beginning of the S phase of the same cycle. This means that cells at the G1 phase would be the ones with 2N DNA contents.