When dominant and recessive alleles express themselves together, it is called

Options

A. Co-dominance
B. Dominance
C. Amphidominance
D. Pseudo dominance

Answer

To solve the question "When dominant and recessive alleles express themselves together, it is called," we can follow these steps:

### Step 1: Understanding Alleles
- Alleles are different forms of a gene that can exist at a specific locus on a chromosome. They can be dominant or recessive.
- Dominant alleles mask the expression of recessive alleles when both are present.

**Hint:** Remember that dominant alleles overpower recessive ones in typical inheritance patterns.

### Step 2: Identifying the Types of Dominance
- There are different types of dominance in genetics:
1. **Complete Dominance**: The dominant allele completely masks the effect of the recessive allele.
2. **Co-Dominance**: Both alleles express themselves equally and visibly in the phenotype.
3. **Incomplete Dominance**: The phenotype is a blend of the two alleles.
4. **Pseudo-Dominance**: A situation where a recessive trait appears dominant due to the lack of a dominant allele.

**Hint:** Think about how traits appear in offspring when both alleles are present.

### Step 3: Analyzing Co-Dominance
- In co-dominance, both dominant and recessive alleles are expressed together in the phenotype. An example is the flower color in Mirabilis jalapa, where a red flower and a white flower can produce a pink flower when crossed.
- This indicates that both traits are visible and neither allele is dominant over the other.

**Hint:** Look for examples where both traits are expressed simultaneously without blending.

### Step 4: Conclusion
- The question specifically asks for the scenario where both dominant and recessive alleles express themselves together. Based on the definitions and examples discussed, the correct answer is **co-dominance**.

**Final Answer:** The answer is **A) Co-Dominance**.