An organism with two identical alleles is said to be -

Options

A. hybrid
B. homozygous
C. heterozygous
D. dominant

Answer

To answer the question "An organism with two identical alleles is said to be -", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Alleles**: Alleles are different forms of a gene that can exist at a specific locus on a chromosome. Each organism inherits two alleles for each gene, one from each parent.

2. **Identifying Types of Alleles**: Alleles can be identical or different. When both alleles are identical, the organism is described using specific terms.

3. **Defining Homozygous**: An organism with two identical alleles is referred to as "homozygous." This term is derived from the Greek words "homo" meaning "same" and "zygous" meaning "joined together."

4. **Types of Homozygous**: Homozygous can be further classified into two types:
- **Homozygous Dominant**: This occurs when both alleles are dominant (e.g., RR).
- **Homozygous Recessive**: This occurs when both alleles are recessive (e.g., rr).

5. **Conclusion**: Therefore, the answer to the question is that an organism with two identical alleles is said to be "homozygous."

### Final Answer:
An organism with two identical alleles is said to be **homozygous**.

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