Question

A plant species has chromosome number of 2n = 12. An individual plant in this species was identified to be tetratomic at chromosome 2. How many chromosomes would you most likely find in a gamete from this plant?

a) 8
b) 7
c) 14
d) 26

Answer 1

A tetratomic chromosome 2 in a plant species with a diploid number of 2n = 12 leads to 8 chromosomes in a gamete because normally a gamete has half the number of chromosomes of the somatic cells. In this case, that would be 6 plus the 2 extra from the tetratomic chromosome.

Step-by-step explanation:

If a plant species has a chromosome number of 2n = 12, and an individual plant within this species is tetratomic at chromosome 2, this means that instead of having two copies of chromosome 2, it has four due to a mutation or error during cell division. Normally, a gamete would have half the number of chromosomes of a somatic cell, so for a 2n = 12 plant species, a gamete would typically have 6 chromosomes. However, because of the abnormality with chromosome 2 being tetratomic, there would be an extra two copies of chromosome 2. Therefore, the gamete from this plant would likely have 6 (standard number for gametes in this species) plus 2 (the extra copies of the tetratomic chromosome), totaling 8 chromosomes in a gamete. So, the answer would be option (a) 8.