Question

David studying population of mold normally having two copies of each chromosomes (2n = 12). A karyotype analysis reveals a single change in chromosome number: AA BBB CC DD EE. Characterize slime mold?

a) triploid
b) monosomic
c) euploid
d) trisomic

Answer 1

The mold characterized by the karyotype 'AA BBB CC DD EE', with an extra chromosome in one group, is trisomic since it has three copies of one chromosome instead of the normal two.

Step-by-step explanation:

In eukaryotic organisms, a euploid individual has the appropriate number of chromosomes for their species, whereas an individual with a chromosome number deviation is described as aneuploid, which includes conditions such as monosomy and trisomy. Given that a normal diploid organism would have two copies of each chromosome (2n = 12) and the karyotype analysis of the mold in question shows the constitution 'AA BBB CC DD EE', it is evident that there is an extra chromosome in one of the chromosome groups (BBB instead of BB). This indicates that the mold is neither euploid nor triploid; instead, it has one additional chromosome in the group, signaling that it is trisomic (there is one extra chromosome in one of the pairs).