Polygenic genes show :-

Options

A. Different karyotypes
B. Different genotypes
C. Different phenotypes
D. None of these

Answer

### Step-by-Step Solution

1. **Understanding Polygenic Genes**:
- Polygenic genes are groups of genes that control the same trait. This means that multiple genes contribute to the expression of a single characteristic.

2. **Definition of Polygenic Traits**:
- A trait that is influenced by more than one gene is called a polygenic trait. Examples include traits like skin color, height, and weight in humans.

3. **Expression of Traits**:
- In polygenic inheritance, the dominant alleles of each gene contribute to the expression of the trait. The full expression of the trait occurs only when multiple dominant alleles from different genes are present.

4. **Genotype and Phenotype Relationship**:
- The genotype (the genetic makeup) of an organism will determine the phenotype (the observable characteristics). Since polygenic traits are influenced by multiple genes, they can result in a variety of phenotypes.

5. **Evaluating the Options**:
- The question provides four options:
- Different karyotypes
- Different genotypes
- Different phenotypes
- None of these

6. **Analyzing Each Option**:
- **Different Karyotypes**: This option is incorrect because karyotypes refer to the number and appearance of chromosomes, which is not directly related to polygenic traits.
- **Different Genotypes**: While polygenic traits can result from different genotypes, the question specifically asks what polygenic genes show, not the genotypes themselves.
- **Different Phenotypes**: This is the correct answer, as polygenic genes are known to produce a range of phenotypes due to the interaction of multiple genes.
- **None of These**: This option is incorrect as we have identified a valid answer.

7. **Conclusion**:
- Therefore, the correct answer to the question "Polygenic genes show:" is **different phenotypes**.