During cell division , the process that causes failure of separation of sister chromatids is called

Options

A. Coincidence
B. interfernce
C. Nondisjuction
D. Complementation

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks for the process that leads to the failure of separation of sister chromatids during cell division.

2. **Identifying Key Terms:**
- Sister chromatids: These are identical copies of a chromosome, connected at a region called the centromere.
- Cell division: This process includes mitosis and meiosis, where chromosomes are separated into daughter cells.

3. **Analyzing the Options:**
The options provided are:
- A) Coincidence
- B) Interference
- C) Non-disjunction
- D) Implementation

4. **Defining Non-disjunction:**
Non-disjunction is a specific term used to describe the failure of homologous chromosomes or sister chromatids to separate properly during cell division. This can occur in both mitosis and meiosis.

5. **Consequences of Non-disjunction:**
When non-disjunction occurs, it results in one daughter cell receiving both copies of a chromosome (or sister chromatids), while the other daughter cell receives none. This leads to an abnormal number of chromosomes in the daughter cells, a condition known as aneuploidy.

6. **Examples of Aneuploidy:**
- Trisomy 21, which is associated with Down syndrome.
- Monosomy, such as Turner syndrome (where there is only one X chromosome).

7. **Conclusion:**
Based on the analysis, the correct answer to the question is **non-disjunction**.

**Final Answer: Non-disjunction**

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