A hereditary mental disorder, partially explained by genomic imprinting and the addition of nucleotides to a triplet repeat near the end of an X chromosome. frameshift mutation A mutation occurring when the number of nucleotides inserted or deleted is not a multiple of 3, thus resulting in improper grouping into codons. free energy A quantity of energy that interrelates entropy (S) and the system's total energy (H); symbolized by G. The change in free energy of a system is calculated by the equation G = Î”H â€“ T Î”S, where T is absolute temperature. free energy of activation The initial investment of energy necessary to start a chemical reaction; also called activation energy. frequency-dependent selection A decline in the reproductive success of a morph resulting from the morph's phenotype becoming too common in a population; a cause of balanced polymorphism in populations. fruit fructus, fruit] A mature ovary of a flower that protects dormant seeds and aids in their dispersal.
an inherited condition in which the X chromosome - is slightly abnormal. Further info.
An X-linked disorder which presents as dysmorphic features (an elongated face, large ears, prominent jaw, and macroorchidism, or enlarged testes, and mental retardation.