A tetraploid female flowering plant and a hexaploid male flowering plant are crossed , endosperm will be

Options

A. heltaploid .
B. triploid.
C. hexaploid.
D. Pentaploid.

Answer

To solve the problem of determining the ploidy level of the endosperm resulting from the cross between a tetraploid female flowering plant and a hexaploid male flowering plant, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Ploidy Levels**:
- The female plant is tetraploid, which means it has a chromosome number of 4n.
- The male plant is hexaploid, which means it has a chromosome number of 6n.

2. **Determine the Gamete Formation**:
- During gamete formation, the chromosome number is halved.
- The female plant will produce gametes with a chromosome number of 2n (half of 4n).
- The male plant will produce gametes with a chromosome number of 3n (half of 6n).

3. **Understanding Endosperm Formation**:
- The endosperm in flowering plants is formed through a process called triple fusion.
- In triple fusion, one male gamete fuses with two polar nuclei from the female gametophyte.

4. **Calculate the Endosperm Ploidy**:
- The endosperm is formed by the fusion of one male gamete (3n) and two polar nuclei (which are derived from the female gamete).
- Since the polar nuclei come from the female gamete, they will contribute 2n to the endosperm.
- Therefore, the total ploidy level of the endosperm will be:
\[ \text{Endosperm Ploidy} = \text{Ploidy from Male Gamete} + \text{Ploidy from Polar Nuclei} = 3n + 2n = 5n \]

5. **Conclusion**:
- The endosperm formed from the cross between a tetraploid female and a hexaploid male will be pentaploid (5n).

### Final Answer:
The endosperm will be 5n (pentaploid).

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