Mark incorrect statements :-
(A) Meiosis involves only a single cycle of DNA replication
(B) Four haploid cells are formed at the end of meiosis-I
( C ) Meiosis occurs in diploid cells
(D) In yeast, cell cycle takes about 90 minutes.

Options

A. A and B
B. A and C
C. Only B
D. All are correct

Answer

To solve the question of marking the incorrect statements regarding meiosis, let's analyze each statement step by step.

### Step-by-Step Solution:

1. **Statement A: Meiosis involves only a single cycle of DNA replication.**
- In meiosis, there is indeed only one cycle of DNA replication that occurs during the S phase of interphase before meiosis begins. Therefore, this statement is **correct**.

2. **Statement B: Four haploid cells are formed at the end of meiosis-I.**
- This statement is **incorrect**. At the end of meiosis I, two haploid cells are formed, not four. The four haploid cells are produced at the end of meiosis II.

3. **Statement C: Meiosis occurs in diploid cells.**
- This statement is **correct**. Meiosis occurs in diploid cells, which undergo division to produce haploid gametes.

4. **Statement D: In yeast, the cell cycle takes about 90 minutes.**
- This statement is also **correct**. In yeast, the cell cycle is relatively short, typically around 90 minutes.

### Summary of Findings:
- **Correct Statements**: A, C, D
- **Incorrect Statement**: B

### Final Answer:
The incorrect statement is **B**: "Four haploid cells are formed at the end of meiosis-I."

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