How many kinds of genotype and phenotype will be produced respectively in trihybrid test cross?

Options

A. 8 and 27
B. 4 and 9
C. 8 and 16
D. 8 and 8

Answer

To solve the question regarding the number of genotypes and phenotypes produced in a trihybrid test cross, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Trihybrid Cross**:
- A trihybrid cross involves three traits, each of which can have two alleles (dominant and recessive).
- For example, let's denote the traits as A, B, and C, where each trait can be either dominant (A, B, C) or recessive (a, b, c).

2. **Calculating Genotypes**:
- In a trihybrid cross, each trait can independently assort. Therefore, the number of possible genotypes can be calculated using the formula \(2^n\), where \(n\) is the number of traits.
- Here, \(n = 3\) (for A, B, and C).
- Thus, the number of genotypes = \(2^3 = 8\).

3. **Calculating Phenotypes**:
- The phenotypes are determined by the expression of the dominant traits. In a trihybrid cross, each trait can either express the dominant phenotype or the recessive phenotype.
- Since there are three traits, the number of possible phenotypes is also \(2^n\).
- Therefore, the number of phenotypes = \(2^3 = 8\).

4. **Conclusion**:
- In a trihybrid test cross, both the number of genotypes and the number of phenotypes produced will be 8.

### Final Answer:
- The number of genotypes produced = 8
- The number of phenotypes produced = 8