Meroblastic cleavage is division.

Options

A. Horizontal
B. Partial/parietal
C. Total
D. Spiral

Answer

**Step-by-Step Solution:**

1. **Understanding Cleavage Types**: Cleavage refers to the series of rapid cell divisions that occur after fertilization. There are different types of cleavage based on the amount of yolk present in the egg.

2. **Identifying Meroblastic Cleavage**: Meroblastic cleavage occurs in eggs that contain a large amount of yolk. In this type of cleavage, only a portion of the egg divides, while the yolk remains undivided.

3. **Comparing with Holoblastic Cleavage**: In contrast, holoblastic cleavage occurs in eggs with little yolk, where the entire zygote divides completely and equally.

4. **Defining Meroblastic Cleavage**: Since meroblastic cleavage involves only partial division of the egg due to the presence of a significant yolk, it is characterized as "partial" or "incomplete" cleavage.

5. **Choosing the Correct Option**: Given the options:
- A) Horizontal
- B) Partial
- C) Total
- D) Spiral

The correct answer is **B) Partial**, as meroblastic cleavage is indeed a type of partial division.

**Final Answer**: Meroblastic cleavage is a partial division.

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