Number of chromosomes is 12 in endosperm. What shall be the number in megaspore mother cell .

Options

A. 8
B. 36
C. 12
D. 18

Explanation

To solve the problem of determining the number of chromosomes in the megaspore mother cell given that the endosperm has 12 chromosomes, we can follow these steps:

### Step-by-step Solution:

1. **Understand the Endosperm Formation**: The endosperm is formed when a male gamete fuses with the central cell (which contains two polar nuclei) of the embryo sac. This fusion results in a triploid (3n) nucleus.

2. **Identify the Chromosome Number of the Endosperm**: We are given that the number of chromosomes in the endosperm is 12. Since the endosperm is triploid, we can express this as:
\[ 3n = 12 \]

3. **Calculate the Value of n**: To find the value of n (the haploid number of chromosomes), we divide both sides of the equation by 3:
\[ n = \frac{12}{3} = 4 \]

4. **Determine the Chromosome Number in the Megaspore Mother Cell**: The megaspore mother cell (MMC) is diploid (2n). Therefore, we can calculate the number of chromosomes in the MMC as:
\[ 2n = 2 \times 4 = 8 \]

5. **Conclusion**: The number of chromosomes in the megaspore mother cell is 8.

### Final Answer:
The number of chromosomes in the megaspore mother cell is **8**.

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