The factors which represent the constrasting pairs of characters are called

Options

A. Dominant and recessive
B. Alleles
C. Homologous pairs
D. Deteminants

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks for the term that refers to factors representing contrasting pairs of characters in genetics.

2. **Identifying the Options:**
The options provided are:
- A. Dominant and recessive
- B. Alleles
- C. Homologous pairs
- D. Determinants

3. **Defining Each Option:**
- **Dominant and Recessive:** These terms describe the relationship between alleles, where the dominant allele masks the effect of the recessive allele in a heterozygous condition.
- **Alleles:** These are different forms of a gene that can exist at a specific locus on a chromosome. Alleles can be dominant or recessive and represent contrasting traits.
- **Homologous Pairs:** These are pairs of chromosomes that have the same structure and gene sequence but may carry different alleles.
- **Determinants:** This term is not commonly used in genetics to describe contrasting traits.

4. **Analyzing the Correct Answer:**
The term that best fits the description of "factors which represent the contrasting pairs of characters" is "alleles." Alleles are the variations of a gene that can result in different traits, such as flower color or seed shape in plants.

5. **Conclusion:**
Therefore, the correct answer to the question is **B. Alleles**.

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