In the monocotyledonous seeds the endosperm is separated from the embryo by a distinct layer known as or The outermost proteinaceous layer of endosperm of maize grain is called

Options

A. Testa
B. Tegmen
C. Aleurone layer
D. Scutellum

Answer

To solve the question regarding the distinct layer that separates the endosperm from the embryo in monocotyledonous seeds, particularly in maize grain, follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure of Monocotyledonous Seeds**:
- Monocotyledonous seeds, such as maize, have a specific structure that includes the endosperm, embryo, and seed coverings.

2. **Identify the Components**:
- The endosperm serves as a nutrient source for the developing embryo. In maize, the endosperm is primarily starchy.

3. **Recognize the Distinct Layer**:
- In monocots, there is a distinct layer that separates the endosperm from the embryo. This layer is crucial for the protection and nourishment of the embryo.

4. **Evaluate the Options**:
- The options provided are:
- A) Testa
- B) Tegmen
- C) Aleurone layer
- D) Scutellum

5. **Analyze Each Option**:
- **Testa**: This is the outer seed coat, which protects the seed but does not separate the endosperm from the embryo.
- **Tegmen**: This is the inner seed coat, which also does not serve as the separating layer between endosperm and embryo.
- **Aleurone layer**: This is the outermost proteinaceous layer of the endosperm in maize and serves to separate the endosperm from the embryo.
- **Scutellum**: This is a shield-shaped structure that is part of the embryo and is closely pressed against the endosperm, but it does not separate them.

6. **Select the Correct Answer**:
- Based on the analysis, the correct answer is **C) Aleurone layer**. This layer is specifically known for its role in separating the endosperm from the embryo in monocotyledonous seeds like maize.

### Final Answer:
The outermost proteinaceous layer of endosperm of maize grain is called the **Aleurone layer**.

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