What is true of cleavage?

Options

A. Daughter cells or blastomeres grow in size equal to paren t cell
B. Blastomeres separate
C. Cytoplasm of blastomeres increases after each division.
D. There is no growth of daughter cells.

Answer

### Step-by-Step Solution:

1. **Understanding Cleavage**: Cleavage refers to the series of rapid mitotic divisions that occur in the zygote after fertilization. This process transforms the single-celled zygote into a multicellular structure.

2. **Formation of Blastula**: As cleavage progresses, the zygote divides to form a structure known as the blastula. This stage is characterized by a specific number of cells, typically reaching a 32-cell stage.

3. **No Growth Phase**: During cleavage, there is no growth phase. This means that while the zygote divides into smaller cells (blastomeres), the overall size of the embryo remains constant.

4. **Size of Daughter Cells**: Although the embryo's size does not change, the size of the individual daughter cells (blastomeres) decreases with each division. This is because the cytoplasm is divided among the new cells, leading to smaller blastomeres.

5. **Conclusion**: Given the options provided, the statement that is true about cleavage is that "there is no growth of the daughter cells." This accurately reflects the nature of cleavage, where the size of the embryo remains the same while the individual cells become smaller.