Which one of the following statements is correct?

Options

A. A sterile pistil is called a staminode
B. The seed in grasses is not endospermic
C. Mango is a parthenocarpic fruit
D. A proteinaceous aleurone layer is present in maize grain

Answer

To determine which statement is correct among the provided options, we need to analyze each statement carefully based on our understanding of flowering plant morphology.

### Step-by-Step Solution:

1. **Understanding Flower Morphology:**
- Flowers consist of four main whorls: calyx (sepals), corolla (petals), androsium (stamens), and gynoecium (pistils).
- The androsium contains the male reproductive organs (stamens), while the gynoecium contains the female reproductive organs (pistils).

2. **Analyzing the First Statement:**
- The first statement claims that a sterile pistil is called a staminode.
- This is incorrect because a staminode refers to a sterile stamen, not a pistil. Therefore, this statement is false.

3. **Analyzing the Second Statement:**
- The second statement asserts that the seed of grasses is non-endospermic.
- This is also incorrect. Grasses (family Poaceae) have seeds that are endospermic, meaning they contain endosperm, which is a tissue that nourishes the developing embryo. Thus, this statement is false.

4. **Analyzing the Third Statement:**
- The third statement suggests that mango is a parthenocarpic fruit.
- This statement is misleading. While parthenocarpic fruits develop without fertilization, mangoes do have seeds, and thus they cannot be classified as parthenocarpic. Therefore, this statement is also false.

5. **Analyzing the Fourth Statement:**
- The fourth statement mentions that in the seeds of monocots, a proteinaceous aileron layer is present.
- This statement is correct. In monocot seeds, such as those of grasses, the endosperm includes a protein-rich layer known as the aileron layer, which separates the endosperm from the embryo.

### Conclusion:
The correct statement is the fourth one, which pertains to the presence of a proteinaceous aileron layer in the seeds of monocots.

---