Question

Down syndrome is an example of trisomy. How many chromosomes will each cell of an individual have in Down syndrome?

46 chromosomes

47 chromosomes

45 chromosomes

Answer 1

47 There are 47 chromosomes in someone with Down syndrome; the 21st pair has an extra chromosome. Most people have 46 chromosomes.

Down syndrome is also known as "Trisomy 21" - a reference to the fact that someone with Down syndrome has 3 pairs of chromosomes on their 21st pair.

Answer 2

thank you

Answer 3

thats what i thought it was

Answer 4

no problem! @Jmmm

Answer 5

:)