Biology 1a
Genetics Terms
Fall 2012
Genetics – study of inheritance of characteristics.
Genomics – looking at the human body in terms of multiple, interacting genes.
Karyotype – chromosome chart that displays the 23 chromosome pairs in size order.
Autosomes – chromosomes that do not carry genes that determine sex.
Sex Chromosomes – chromosomes ( X and Y) that include genes that determine sex.
Alleles – genes for the same trait that exist in variant forms.
Homozygous – two identical alleles for a particular gene.
Heterozygous – two different alleles for a particular gene.
Genotype – the particular combination of alleles in a person’s genome.
Phenotype – the appearance or health condition of the individual that develops as a result of the ways
the genes are expressed.
Wild type – associated phenotype is normal function or the most common expression in a particular
population.
Mutant – a change from wild type, producing an uncommon phenotype.
Dominant – allele whose action masks that of another allele.
Recessive – allele whose expression is masked.
Pedigree – a diagram that depicts family relationships and known genotypes and phenotypes.
Incomplete dominance – the heterozygous phenotype is intermediate between that of either
homozygote.
Codominant – different alleles that are both expressed in a heterozygote.