Definition of Long arm of a chromosome
Long arm of a chromosome: The long arm of a chromosome is termed the q arm. All human chromosomes have 2 arms, the p (short) arm and the q (long) arm. They are separated from each other only by a primary constriction, the centromere, the point at which the chromosome is attached to the spindle during cell division. The symbol "p" stands for "petit", small in French, while "q" was chosen merely because it was the next letter in the alphabet.
Last Editorial Review: 4/27/2011 5:27:15 PM
Back to MedTerms online medical dictionary A-Z List
Need help identifying pills and medications?
Get the latest health and medical information delivered direct to your inbox FREE!