After fertilization, in the embryo sac which will grow faster?

Options

A. Nucellus
B. Endosperm
C. Pollen tube
D. Synergids

Answer

To solve the question "After fertilization, in the embryo sac which will grow faster?", we can break down the process of fertilization and the subsequent development in the embryo sac step by step.

### Step-by-Step Solution:

1. **Understanding Double Fertilization**:
- In angiosperms, double fertilization occurs, which involves two fertilization events. The first event is syngamy, where one male gamete (sperm) fuses with the egg cell to form a zygote.

**Hint**: Remember that double fertilization is a unique feature of angiosperms.

2. **Formation of Zygote**:
- The zygote is formed from the fusion of the egg and the first male gamete. After fertilization, the zygote undergoes a period of rest before it begins to develop.

**Hint**: The zygote is the initial cell that will develop into the embryo.

3. **Triple Fusion**:
- The second male gamete fuses with the two polar nuclei present in the embryo sac, forming a primary endosperm nucleus. This process is known as triple fusion.

**Hint**: The primary endosperm nucleus is crucial for nourishing the developing embryo.

4. **Endosperm Development**:
- The primary endosperm nucleus undergoes mitosis to form the endosperm, which is a tissue that provides nutrition to the developing embryo. This process occurs relatively quickly after fertilization.

**Hint**: Endosperm is vital for the embryo's growth, as it supplies the necessary nutrients.

5. **Embryo Development**:
- After the endosperm is formed, the zygote will begin to divide and develop into the embryo. However, this process starts after the endosperm has already begun to grow.

**Hint**: The embryo relies on the endosperm for nutrition during its early development.

6. **Conclusion**:
- Since the endosperm develops rapidly to provide nourishment, it is the structure that grows faster after fertilization in the embryo sac.

**Final Answer**: The endosperm grows faster after fertilization in the embryo sac.

### Summary:
In conclusion, after fertilization in the embryo sac, the endosperm grows faster than the embryo. This is because the endosperm is responsible for providing the necessary nutrients to support the developing embryo.