Question

How many chromosomes are present in the image? How many chromatids?

• A. 4 chromosomes, 4 chromatids
• B. 4 chromosomes 8 chromatids
• C. 8 chromosomes, 4 chromatids
• D. 8 chromosomes 8 chromatids

Answer 1

The correct option is D 8 chromosomes 8 chromatids

As a cell prepares to divide, it must make a copy of each of its chromosomes. The two copies of a chromosome are called sister chromatids. They are attached to each at the centromere.
As long as the sister chromatids are connected at the centromere, they are still considered to be one chromosome. However, as soon as they are pulled apart during cell division, each is considered a separate chromosome. So in the image there are 8 chromosomes each consisting of a single chromatid.