A woman with 47 chromosomes due to three copies of chromosome 21 is characterized by

Options

A. Down syndrome
B. Triploidy
C. Turner's syndrome
D. Super femaleness

Answer

To solve the question regarding a woman with 47 chromosomes due to three copies of chromosome 21, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Chromosome Count**:
- Humans typically have 46 chromosomes, arranged in 23 pairs. Each pair consists of one chromosome from each parent.

2. **Identifying the Condition**:
- The question states that the woman has 47 chromosomes. This indicates an abnormality in the number of chromosomes.

3. **Analyzing the Extra Chromosome**:
- The presence of three copies of chromosome 21 suggests a condition known as "trisomy 21". In normal circumstances, there should be two copies of chromosome 21.

4. **Recognizing Down Syndrome**:
- Trisomy 21 is specifically known as Down syndrome. This genetic disorder is characterized by physical growth delays, characteristic facial features, and mild to moderate intellectual disability.

5. **Eliminating Other Options**:
- The other options provided (triploidy, Turner syndrome, and superfemaleness) do not fit the description:
- **Triploidy**: This condition involves having three complete sets of chromosomes (69 total), not just an extra chromosome 21.
- **Turner Syndrome**: This is characterized by a missing X chromosome (45 chromosomes total, with a typical karyotype of 44 + X0).
- **Superfemaleness**: This condition is associated with an extra X chromosome (47 chromosomes total, with a karyotype of 44 + XXX).

6. **Conclusion**:
- Therefore, the correct answer to the question is that the woman with 47 chromosomes due to three copies of chromosome 21 is characterized by **Down syndrome**.