In Pinus, the pollen grain has 6 chromosomes. What is the number of chromosomes in its endoperm

Options

A. 12
B. 18
C. 6
D. 24

Answer

To determine the number of chromosomes in the endosperm of Pinus, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Chromosome Number in Pollen Grain**:
- The question states that the pollen grain of Pinus has 6 chromosomes.

2. **Understand the Nature of Pollen Grain**:
- Pollen grains are the male gametes in plants. In terms of chromosome number, they are haploid, which means they contain half the number of chromosomes compared to the diploid sporophyte generation.

3. **Determine the Chromosome Number of the Female Gamete**:
- Since the pollen grain (male gamete) has 6 chromosomes (N = 6), the female gamete (ovule) will also have the same haploid number of chromosomes, which is also 6.

4. **Understand the Formation of Endosperm**:
- In gymnosperms like Pinus, the endosperm is formed before fertilization. It is a tissue that provides nourishment to the developing embryo.

5. **Determine the Chromosome Number of the Endosperm**:
- The endosperm in gymnosperms is haploid, just like the gametes. Therefore, since the haploid number is 6, the endosperm will also have 6 chromosomes.

6. **Conclusion**:
- The number of chromosomes in the endosperm of Pinus is 6.

### Final Answer:
The number of chromosomes in the endosperm of Pinus is **6**.

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