Q6.2. How many sister chromatids does the cell depicted below have? Submit chromatids
The correct answer and explanation is:
To accurately answer your question about how many sister chromatids the cell depicted has, I’d need to know the stage of the cell cycle or a description of the depicted cell. Without that, I’ll provide a general explanation based on common scenarios in cell division.
Explanation of Sister Chromatids:
Sister chromatids are identical copies of a chromosome, connected at a central region called the centromere. They are formed during the S phase of interphase when DNA replication occurs. The number of chromatids varies depending on the cell cycle stage:
- G1 Phase: No DNA replication has occurred yet, so each chromosome exists as a single chromatid. For a human cell with 46 chromosomes, there are 46 chromatids.
- S Phase: DNA replication doubles the genetic material, resulting in 92 chromatids (46 chromosomes, each with 2 sister chromatids).
- G2 Phase: The cell contains 92 chromatids because the DNA remains replicated.
- Mitosis:
- Prophase and Metaphase: The chromatids remain connected, totaling 92 chromatids.
- Anaphase: Sister chromatids separate, and each is now considered an individual chromosome. There are 92 individual chromosomes, no longer chromatids.
- Telophase: Chromosomes begin to decondense, and eventually, each daughter cell ends up with 46 chromosomes.
Answer:
If the depicted cell is in G2, prophase, or metaphase, it has 92 sister chromatids (for a diploid human cell). If it’s in G1, it has 46 chromatids. If it’s in anaphase or telophase, chromatids are no longer paired, and the number depends on the stage’s interpretation.
Confirm the stage of the cell to provide a precise count. Let me know if more details are needed!