Although Dolly was only three years old,her chromosomes had the length of a 9- to 10-year-old sheep.Which of the following best describes why this occurred?
A) The cell lines that created Dolly were aged prematurely in the lab and thus became longer.
B) Nonhomologous recombination occurred, which caused Dolly's chromosomes to shorten.
C) A mutation enhanced the rate of aging of Dolly's chromosomes.
D) Dolly was not a clone.
E) The telomeres of the somatic cells that Dolly originated from were already shortening.

Question

Quizplus · Accepted Answer

Telomeres are the protective caps at the ends of chromosomes that shorten with each round of cell division. As Dolly was cloned from a somatic cell, her telomeres were already shortened, which could explain the longer length of her chromosomes at only three years old.

Although Dolly Was Only Three Years Old,her Chromosomes Had the Length