The mature seeds of plants such as gram and peas, possess no endosperm, because

Options

A. these plants are not angiosperms
B. there is no double fertilisation in them
C. endosperm is not formed in them
D. endosperm gets used up by the developing embryo during seed development.

Explanation

To answer the question regarding why the mature seeds of plants such as gram and peas possess no endosperm, we can break down the explanation into several steps:

### Step-by-Step Solution:

1. **Understanding Seed Structure**:
- Seeds are composed of three main parts: the embryo, the endosperm, and the seed coat. The embryo develops into the new plant, while the endosperm serves as a food reserve for the developing embryo.

2. **Types of Angiosperms**:
- Angiosperms are divided into two categories: dicots (dicotyledons) and monocots (monocotyledons).
- Dicot seeds, such as those from gram and peas, have two cotyledons, while monocot seeds have one.

3. **Fertilization Process**:
- In dicots, during fertilization, both the zygote and the endosperm are formed. The endosperm is created through a process called double fertilization, where one sperm fertilizes the egg (forming the zygote) and another sperm fuses with two polar nuclei to form the endosperm.

4. **Development of the Seed**:
- As the seed develops, the embryo grows and utilizes the nutrients stored in the endosperm. In the case of dicots, the endosperm is completely consumed by the developing embryo.

5. **Final Outcome**:
- By the time the seed matures, there is no endosperm left, resulting in what is known as non-endospermic seeds. This is why mature seeds of plants like gram and peas do not possess any endosperm.

### Conclusion:
The mature seeds of plants such as gram and peas possess no endosperm because the endosperm gets used up by the developing embryo during seed development.

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