How many SAT- chromosomes are present in human diploid cell ?

Options

A. 23 pairs
B. 5pairs
C. 10pairs
D. 3pairs

Answer

To determine how many SAT-chromosomes (satellite chromosomes) are present in a human diploid cell, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Chromosome Types**:
- In humans, chromosomes can be classified into different types based on their structure. Satellite chromosomes, also known as acrocentric chromosomes, have a secondary constriction that gives them a satellite-like appearance.

2. **Identifying Human Chromosome Count**:
- Humans have a total of 46 chromosomes in a diploid cell, which are organized into 23 pairs.

3. **Defining SAT-Chromosomes**:
- Satellite chromosomes are specifically those that contain a nucleolar organizer region (NOR) which is essential for the formation of the nucleolus.

4. **Counting SAT-Chromosomes**:
- In humans, there are 5 pairs of acrocentric chromosomes that are classified as satellite chromosomes. These are:
- Chromosome 13
- Chromosome 14
- Chromosome 15
- Chromosome 21
- Chromosome 22

5. **Conclusion**:
- Therefore, the total number of SAT-chromosomes in a human diploid cell is 5 pairs, which equals 10 individual SAT-chromosomes.

### Final Answer:
- The number of SAT-chromosomes present in a human diploid cell is **5 pairs**.

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