Types of cleavage in centrolecithal egg is

Options

A. Spiral
B. Superficial
C. Discoidal
D. Unequal holoblastic

Answer

### Step-by-Step Solution:

1. **Understanding Centrolecithal Eggs**:
- Centrolecithal eggs are characterized by having a large amount of yolk concentrated in the center of the egg. This type of egg is typically found in certain invertebrates.

2. **Defining Cleavage**:
- Cleavage refers to the series of rapid cell divisions that occur after fertilization, leading to the formation of the embryo. The type of cleavage is influenced by the distribution of yolk in the egg.

3. **Types of Cleavage**:
- There are several types of cleavage patterns, including:
- **Holoblastic Cleavage**: Complete division of the egg, typical in eggs with little yolk.
- **Meroblastic Cleavage**: Partial division of the egg, typical in eggs with a lot of yolk.

4. **Identifying the Type of Cleavage in Centrolecithal Eggs**:
- In centrolecithal eggs, the cleavage is classified as meroblastic because the cleavage furrow does not penetrate the entire egg but only divides the cytoplasm surrounding the yolk.
- Specifically, the type of meroblastic cleavage seen in centrolecithal eggs is **superficial cleavage**. This means that the cleavage occurs only in the cytoplasm surrounding the yolk, and the yolk itself remains undivided.

5. **Conclusion**:
- Therefore, the type of cleavage in centrolecithal eggs is **superficial cleavage**.