The number of linkage groups present in a diploid animal is

Options

A. equal to the total number of choromsomes
B. half of the total number of chromosomes
C. a quarter of the total number of chromosomes
D. two-thirds of the total number of chromosomes

Answer

To solve the question regarding the number of linkage groups present in a diploid animal, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Linkage Groups**:
- Linkage groups refer to groups of genes that are located on the same chromosome. These genes tend to be inherited together due to their physical proximity on the chromosome.

2. **Identify the Chromosome Number in Diploid Organisms**:
- A diploid organism has two sets of chromosomes, denoted as 2n, where "n" is the number of unique chromosomes. For example, if an organism has 46 chromosomes, it is diploid (2n = 46), meaning n = 23.

3. **Determine the Number of Linkage Groups**:
- The number of linkage groups in a diploid organism is equal to the number of unique chromosomes (n). This is because each chromosome can be considered a linkage group.

4. **Apply the Formula**:
- The formula to calculate the number of linkage groups in a diploid organism is:
\[ \text{Number of Linkage Groups} = \frac{\text{Total Number of Chromosomes}}{2} = \frac{2n}{2} = n \]
- Therefore, the number of linkage groups is half the total number of chromosomes.

5. **Evaluate the Options**:
- If the options provided are:
- A) Equal to the total number of chromosomes
- B) Half of the total number of chromosomes
- C) A quarter of the total number of chromosomes
- D) Two-thirds of the total number of chromosomes
- The correct answer is option B, as it correctly states that the number of linkage groups is half of the total number of chromosomes.

### Final Answer:
The number of linkage groups present in a diploid animal is **half of the total number of chromosomes** (Option B).

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