. In Pinus, endosperm cells have 30 chromosomes then how many chromosomes are present in sieve cells :-

Options

A. 30
B. 60
C. 10
D. 15

Answer

To solve the question regarding the number of chromosomes in sieve cells of Pinus, follow these steps:

### Step-by-Step Solution:

1. **Identify the Organism and Its Characteristics**:
- Pinus is a Gymnosperm. Gymnosperms are a group of seed-producing plants that includes conifers.

2. **Understand the Chromosome Count in Endosperm**:
- The question states that the endosperm cells of Pinus have 30 chromosomes.

3. **Determine the Nature of Endosperm**:
- In Gymnosperms like Pinus, the endosperm is haploid (N). This means it has a single set of chromosomes.

4. **Identify the Nature of Sieve Cells**:
- Sieve cells are part of the plant's phloem and are responsible for the transport of nutrients. Sieve cells are diploid (2N), meaning they have two sets of chromosomes.

5. **Calculate the Chromosome Number in Sieve Cells**:
- Since the endosperm is haploid (N = 30), to find the number of chromosomes in the diploid sieve cells (2N), you need to double the haploid number.
- Therefore, the number of chromosomes in sieve cells = 2 * 30 = 60 chromosomes.

6. **Conclusion**:
- The number of chromosomes present in the sieve cells of Pinus is 60.

### Final Answer:
The number of chromosomes in sieve cells of Pinus is **60**.

---