Question

Which of the following explanations best describes the difference between cystic fibrosis and Down syndrome?

A. Down syndrome is caused by a DNA mutation, while cystic fibrosis is caused by a change in the structure of a chromosome.


B. Down syndrome is caused by change in the number of a chromosome, while cystic fibrosis is caused by a DNA mutation.


C. Down syndrome is caused by a change in the number of a chromosome, while cystic fibrosis is caused by a change in the structure of a chromosome.


D. Down syndrome is caused by a DNA mutation, while cystic fibrosis is caused by a change in the number of a chromosome.

Answer 1

Down syndrome is caused by a change in the number of a chromosome, while cystic fibrosis is caused by a mutation in a single gene.

Step-by-step explanation:

The best explanation for the difference between cystic fibrosis and Down syndrome is option C. Down syndrome is caused by a change in the number of a chromosome, specifically having three copies of chromosome 21 (trisomy 21). On the other hand, cystic fibrosis is caused by a mutation in a single gene called CFTR. This mutation leads to the production of a faulty protein that affects the movement of salt in and out of cells, resulting in the production of thick and sticky mucus.

Answer 2

B. Is the best described difference between cystic fibrosis and Down syndrome.