172k views
2 votes
How many chromosomes are there in a somatic cell of a person with Down syndrome (trisomy of chromosome 21)?

A) 46 chromosomes; 22 autosomes.
B) 47 chromosomes; 23 autosomes.
C) 48 chromosomes; 24 autosomes.
D) 45 chromosomes; 21 autosomes.

User Afrischke
by
8.8k points

1 Answer

6 votes

Final answer:

A person with Down syndrome has trisomy of chromosome 21, resulting in 47 chromosomes in their somatic cells. The correct answer is option B) 47 chromosomes; 23 autosomes.

Step-by-step explanation:

A person with Down syndrome has trisomy of chromosome 21, which means they have an extra copy of chromosome 21. Therefore, the correct answer is option B) 47 chromosomes; 23 autosomes. In a somatic cell of a person with Down syndrome, there are 47 chromosomes instead of the usual 46.

User Alicyn
by
8.5k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.