Tapetum is

Options

A. Inner nutritive layer that persists at maturity
B. Inner nutritive layer that degenerates at maturity
C. Outer nutritive layer that degenerates at maturity
D. Outer nutritive layer that persists at maturity.

Answer

**Step-by-Step Solution:**

1. **Understanding the Structure**: The tapetum is a layer found in the anther of flowering plants. It is important to know where it is located to understand its function.

2. **Identifying the Location**: The tapetum is the innermost layer of the anther wall. It surrounds the sporogenous tissue, which is responsible for producing pollen grains.

3. **Analyzing the Characteristics**: The cells of the tapetum are characterized by having dense cytoplasm and multiple nuclei. This indicates that they are metabolically active and play a significant role in the development of pollen.

4. **Determining the Function**: The primary role of the tapetum is to provide nourishment to the developing pollen grains. This is crucial for the proper development of pollen, which is essential for reproduction in flowering plants.

5. **Considering the Maturity Stage**: At maturity, the tapetum degenerates. This means that it does not persist throughout the life of the plant but instead breaks down once its role in nourishing the pollen grains is complete.

6. **Selecting the Correct Option**: Based on the information gathered, the correct answer to the question "Tapetum is" is: "inner nutritive layer that degenerates at maturity."

**Final Answer**: The correct option is B: inner nutritive layer that degenerates at maturity.

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