Genotype of male plant is TT and genotype of female plant is tt. What would be the genotype of endosperm?

Options

A. TTt
B. Ttt
C. Tt
D. tt

Answer

To determine the genotype of the endosperm when the male plant has the genotype TT and the female plant has the genotype tt, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Genotypes**:
- Male plant genotype: TT (homozygous dominant)
- Female plant genotype: tt (homozygous recessive)

2. **Understand the Process of Double Fertilization**:
- In flowering plants, double fertilization occurs where one male gamete fertilizes the egg cell (female gamete) to form the zygote, and the other male gamete fuses with the two polar nuclei in the embryo sac to form the endosperm.

3. **Determine the Gametes**:
- The male plant (TT) produces male gametes (pollen) that are all T (since it is homozygous).
- The female plant (tt) produces female gametes (ovules) that are all t (since it is also homozygous).

4. **Fertilization Events**:
- One male gamete (T) fuses with one female gamete (t) to form the zygote, which has the genotype Tt (diploid).
- The other male gamete (T) fuses with the two polar nuclei (which are t and t) to form the endosperm.

5. **Genotype of the Endosperm**:
- The fusion of the male gamete (T) with the polar nuclei (tt) results in a triploid endosperm with the genotype Ttt.

6. **Final Answer**:
- Therefore, the genotype of the endosperm is Ttt.