How many types of gametes are expected from a plant with genotype Pp Qq, provided there occurs independent assortment ?

Options

A. 4
B. 8
C. 2
D. 1

Answer

To determine how many types of gametes are expected from a plant with the genotype Pp Qq under the condition of independent assortment, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Genotype**: The given genotype is Pp Qq. This indicates that the plant is heterozygous for both traits (P and Q).

2. **Understand Independent Assortment**: Independent assortment means that the alleles for different traits segregate independently during gamete formation. This means that the inheritance of one trait does not affect the inheritance of another.

3. **Count the Heterozygous Alleles**: In the genotype Pp Qq, we have two heterozygous pairs:
- For the first trait (P), we have Pp (which can produce P or p).
- For the second trait (Q), we have Qq (which can produce Q or q).

4. **Use the Formula for Gamete Formation**: The formula to calculate the number of different gametes is:
\[ \text{Number of gametes} = 2^n \]
where \( n \) is the number of heterozygous gene pairs.

5. **Calculate n**: In this case, we have:
- \( n = 2 \) (since there are two heterozygous pairs: Pp and Qq).

6. **Calculate the Number of Gametes**:
\[ \text{Number of gametes} = 2^2 = 4 \]

7. **List the Possible Gametes**: The possible combinations of gametes can be:
- PQ (from P and Q)
- Pq (from P and q)
- pQ (from p and Q)
- pq (from p and q)

8. **Conclusion**: Therefore, the total number of different types of gametes that can be formed from the genotype Pp Qq, under independent assortment, is 4.

### Final Answer:
**4 types of gametes are expected.**