Organism having one chromosome pair less to the normal somatic complement of the species is

A. Monosomic

B. Nullisomic

C. Trisomic

D. Tetraomic

Answer: Option B

Solution(By Examveda Team)

An organism having one chromosome pair less than the normal somatic complement of the species is Nullisomic.
Nullisomic is a genetic condition involving the lack of both the normal chromosomal pairs for a species (2n-2). Humans with this condition will not survive.
Nullisomy is caused by non-disjunction, during meiosis that causes two of the gametes to have no chromosomal material, leaving the other two gametes to have double the amount of chromosomal material.