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

Verified step by step guidance

1. Step 1: Understand the cell cycle. The cell cycle is a series of events that take place in a cell leading to its division and duplication. It consists of four main phases: G1, S, G2, and M.
2. Step 2: Identify the relevant phases. In this problem, we are interested in the G1 and S phases. The G1 phase is a period of activity where cells grow and carry out normal functions. The S phase is when DNA replication occurs.
3. Step 3: Understand DNA replication. During the S phase, the amount of DNA in the cell doubles as each DNA molecule is replicated to produce two identical copies.
4. Step 4: Apply this understanding to the problem. If a cell contains 4 picograms of DNA at the G1 phase, then after DNA replication in the S phase, the amount of DNA will double.
5. Step 5: Therefore, the cell will contain twice the amount of DNA at the end of the S phase compared to the G1 phase.

Key Concepts

Cell Cycle

The cell cycle is a series of phases that a cell goes through to grow and divide. It consists of interphase (which includes G1, S, and G2 phases) and the mitotic phase (M phase). During the S phase, DNA replication occurs, resulting in the duplication of the cell's genetic material.

DNA Replication

DNA replication is the process by which a cell makes an identical copy of its DNA. This occurs during the S phase of the cell cycle, where each chromosome is duplicated, leading to two sister chromatids for each chromosome. If a cell starts with a certain amount of DNA, it will double that amount by the end of the S phase.

Picograms of DNA

A picogram is a unit of mass equal to one trillionth of a gram (10^-12 grams). In the context of DNA, it is used to measure the amount of genetic material present in a cell. Understanding the measurement in picograms helps in quantifying the DNA content before and after replication during the cell cycle.