Amont of yolk and its distribution are changed in the egg. Which one is affected?

Options

A. Pattern of cleavage
B. Formation of zygote
C. Number of blastomeres
D. Fertilization

Answer

To solve the question regarding how the amount of yolk and its distribution in the egg affects certain processes, we can break down the reasoning step-by-step.

### Step-by-Step Solution:

1. **Understanding Yolk in Eggs**:
- Yolk is a nutrient-rich substance found in eggs that provides energy and nourishment to the developing embryo. The amount and distribution of yolk can vary significantly among different species.

2. **Identifying the Options**:
- The options provided are:
- A) Pattern of cleavage
- B) Formation of zygote
- C) Number of plastomers
- D) De-fertilization

3. **Analyzing the Pattern of Cleavage**:
- Cleavage refers to the series of rapid cell divisions that occur after fertilization. The pattern of cleavage can be influenced by the amount and distribution of yolk in the egg.
- There are two main types of cleavage:
- **Holoblastic Cleavage**: This occurs in eggs with moderate to low amounts of yolk. The cleavage furrows pass through the entire egg, dividing it completely (e.g., in frogs and humans).
- **Meroblastic Cleavage**: This occurs in eggs with a large amount of yolk. The cleavage furrows do not pass through the entire egg, resulting in incomplete division (e.g., in birds and insects).

4. **Evaluating Other Options**:
- **Formation of Zygote**: This is the initial stage after fertilization and is not directly affected by yolk distribution.
- **Number of Plastomers**: Plastomers are not a commonly referenced term in the context of yolk and cleavage patterns.
- **De-fertilization**: This refers to the process where fertilization does not occur or is reversed and is not directly related to yolk distribution.

5. **Conclusion**:
- Since the amount and distribution of yolk directly influence the pattern of cleavage, the correct answer to the question is **A) Pattern of cleavage**.

### Final Answer:
The correct option is **A) Pattern of cleavage**.