List of genetics pages:A

Acentric chromosome - A chromosome having no centromere
Acrocentric chromosome - A chromosome with an off-centre centromere, giving it a long arm and a short arm
Additive genetic variance - Variation arising additive effects of genes on phenotype
Adenine - One of the four organic bases in DNA
Allele - One of multiple versions of a gene
Allelic frequency - Proportion of individuals in a population carrying a specific allele
Aminoacyl-tRNA - Transfer RNA molecule carrying a specific amino acid
Aneuploidy - Condition where one or more chromosomes is either missing or duplicated
Anticodon - Three base area on tRNA molecule complimentary to a codon on mRNA
Attenuation - Regulatory mechanism in bacteria which causes RNA polymerase to terminate transcription
Autonomously replicating sequences - Non-chromosomal DNA capable of replicating itself
Autosome - Chromosome which is not a sex-chromosome
Auxotrophic mutation - Mutation which disrupts production of molecules essential for growth