Learn something new every day More Info... by email The study of
cellular changes, or mutations, is a prime research area in
genetics. One area of interest to scientists concerns how an
organism can overcome genetic abnormalities to retain the
normalized version of a trait. Complementation tests can address
this issue by studying organisms with genetic mutations and
their offspring. If an offspring trait is expressed normally
even in the presence of known genetic mutations, then the
genetic relationship is said to be complementary. In order to
understand complementation, certain genetic terms must first be
defined. Gene expressions are at the most basic level of
complementation, and genes are small units within an organism
that hold and pass on traits. They are comprised of
deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). The
different forms of a gene are known as alleles, and each gene is
stored on DNA structures called chromosomes. A gene may be
expressed in the form of letter symbols called genotype