| A | B |
| Mutation | a change in DNA |
| Germ cell mutations | mutations taking place in sex cells |
| Somatic mutations | mutations taking place in body cells |
| Deletion | when a piece of a chromosome breaks off |
| Inversion | when a pieve breaks from a chromosome and reattaches itself to the chromosome in reverse orientation |
| Translocation | a broken pieve attaches to a nonhomologous chromosme |
| Nondisjunction | when a replicated chromosome pair fails to seperate during cell division |
| Point Mutation | remocal of a single nitrogen base |
| Frame shift mutation | the addition or deletion of a nitrogen base, a type of point mutation |
| Mutagens | enviromental factors that damage DNA |
| Ames test | a procedure to identify mutagenic substances |
| Sex chromosomes | chromosomes that determines the gender of someone |
| Autosomes | all other chromosomes not included in sex determination |
| Linkage group | the group of genes located on one chromosome |
| Chromosme map | a diagram of allele psotitions on a particular chromosome |
| Map unit | a unit in chromosome mapping equal to a 1 percent occurrence of crossing-over |
| Population sampling | a tool for studying human genetics where researchers select a small number of individuals that represent the whole population |
| Pedigree | a family record that shows how a trait is inherited over several generations |
| Carrier | someone who is heterozygous for a trait |
| Sickle-cell disease | a single allele disorger that operates in a codominant system |
| Huntington disease | a single allele trait that is caused by a dominant allele |
| Genetic marker | a short section of DNA that indicates the presence of an allele that codes for a trait |
| Polygenic trait | a trait that is controlled by two or more genes |
| Antigen | a substance that causes the body to produce an antibody |
| Hemophilia | a recessive sex-linked trait that is found primarily in males |
| Sex-influenced traits | the presence of male or female sex hormones influencing the expression of certain human traits |
| Monosomy | A condition of a zygote with 45 chromosomes has only one of a particular chromosome |
| Trisomy | A zygote with 47 chromosomes having threee of a particular chromosome |
| Down syndrome | a disorder characterized by mental illness, wrinkles above the eyes, and weak muscles |
| Genetic screening | an examination of a person's genetic makeup |
| Karyotype | a picture of an individual's chromosomes |
| Genetic counseling | a trpe of counseling that informs them about problems that could affect their offspring |
| Amniocentesis | the use of a needle and syringle to remoce a small amount of amniotic fluid |
| Fetoscopy | the insertion of a tiny camera throug ha small incision of the uterus |
| Ultrasound | a technique where high-frequency sound waves bounce off the fetus, forming an image |
| Chlorian villi sampling | the analyzing of a sample of the chrion villi |