Complex Inheritance & Human Hereditary Vocab

autosome

chromosome that is not a sex chromosome

carrier

individual heterozygous for a recessive disorder such as cystic fibrosis or Tay-Sachs disease

codominance

complex inheritance pattern that occurs when neither allele is dominant and both alleles are expressed

epistatis

interaction between alleles in which one allele hides the effects of another allele

incomplete dominance

complex inheritance pattern in which the heterozygous phenotype is intermediate between those of the two homozygous parent organisms

karyotype

micrograph in which the pairs of homologous chromosomes are arranged in decreasing size

multiple alleles

having more than two alleles for a specific trait

nondisjunction

Cell division in which the sister chromatids do not separate correctly, resulting in gamete with an abnormal number of chromosomes.

pedigree

diagrammed family history that is used to study inheritance patterns of a trait through several generations and that can be used to predict disorders in future offspring

polygenic trait

characteristic, such as eye color or skin color, that results from the interaction of multiple gene pairs

sex chromosome

X or Y chromosome; paired sex chromosomes determine an individual's gender - XX individuals are female and XY individuals are male

sex-linked trait

characteristic, such as red-green color blindness, controlled by genes on the X chromosome; also called an X-linked trait

telomere

protective cap made of DNA that is found on the ends of a chromosome