| A | B |
|---|
| sex chromosome | chromosomes that determine sex (XX or XY) |
| autosome | all chromosomes in an organism that do not determine sex |
| sex-linked trait | a trait that has alleles on the sex chromosomes |
| linked gene | pairs of genes that tend to be inherited together |
| chromosome map | a linear diagram of a chromosome with location of genes on it |
| map unit | an increment of 1% in crossing over on a chromosome |
| germ-cell mutations | mutations that occur in an organism's gametes |
| somatic-cell mutations | mutations that occur in an organism's body cells |
| lethal mutation | a mutation that causes death...usually before birth |
| deletion | loss of a piece of chromosome |
| inversion | a piece of chromosome breaks off, flips, and reattaches |
| translocation | a piece of chromosome breaks off and reattaches to a nonhomologous chromosome |
| nondisjunction | when homologous chromosomes don't separate during meiosis |
| point mutation | substitution, addition, or removal of a single nucleotide |
| substitution | one nucleotide replaces another |
| frameshift mutation | when a deletion or addition causes incorrect grouping downstream on the DNA |
| insertion mutation | one or more nucleotides added to a gene |
| pedigree | a diagram that shows how a trait is inherited over several generations |
| carrier | have one copy of the recessive allele, but not the trait/disease |
| genetic disorder | diseases or conditions that have a genetic basis |
| polygenic | traits determined by many genes (eye color/skin color) |
| complex character | traits influenced by many genes and the environment (skin color) |
| multiple allele | genes with more than two alleles like blood type |
| codominance | where both alleles are expressed in a heterozygote (AB blood type) |
| incomplete dominance | a trait where two alleles "blend" (wavy hair) |
| sex-influenced trait | where alleles may be influence by hormones (pattern baldness) |
| Huntington's Disease | autosomal dominant disease that effect's a persons motor and mental abilities |
| amniocentesis | analyzing amniotic fluid to test for genetic disorders |
| chorionic villi sampling | taking a sample of the chorionic villi cells to test for genetic disorders |
| genetic counseling | a person that tells a couple about genetic disorders |
| gene therapy | a technique to replace a defective gene with a healthy one |
