Different forms of a gene are called

Options

A. Heterozygotes
B. Alleles
C. Complementary genes
D. Supplementary genes.

Answer

**Step-by-Step Solution:**

1. **Understanding Genes**: A gene is a segment of DNA that contains the instructions for building a specific protein or set of proteins. Each gene can have different variations.

2. **Defining Alleles**: Different forms of a gene are known as alleles. Alleles can vary in their sequence and can lead to different traits or characteristics.

3. **Identifying Heterozygotes**: Heterozygotes refer to individuals who have two different alleles for a particular gene. This term describes the genetic makeup but does not define the forms of the gene itself.

4. **Complementary and Supplementary Genes**: Complementary genes are genes that interact with each other to produce a certain phenotype, while supplementary genes refer to non-allelic genes that can also influence a trait. However, these terms do not refer to the different forms of a single gene.

5. **Conclusion**: The correct term for different forms of a gene is "alleles." Therefore, the answer to the question is that different forms of a gene are called alleles.

**Final Answer**: Different forms of a gene are called alleles.

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