| A | B |
|---|
| genes | sections of chromosomes |
| DNA | chromosomes(and therefore genes) are made of this |
| 46 | total number of chromosomes in each cell |
| 23 | number of chromosomes from each parent |
| prenatal development | the development of a zygote, embryo, and fetus before birth |
| hereditary | all traits passed down from one generation to the next |
| chromosomes | a threadlike structure that carries genes in living cells |
| dominant traits | traits that always show in a person even if only one gene of the pair is inherited for the trait |
| recessive traits | traits that typically do not show in a person unless both genes for the trait are inherited |
| cystic fibrosis | a genetic disease that results in secretion of thick mucus that blocks internal passages (i.e. lungs causing respiratory infections) |
| birth defect | an abnormality, present at birth, that affects the structure or function of the body and may threaten a baby's health |
| muscular dystrophy | a progressive weakness and shrinking of the muscles most commonly inherited |
| sickle cell anemia | caused by inheriting defective rescessive genes from both parents, more commonly occurs in African-Americans |
| PKU | a condition in which the body is unable to process and use a specific protein that is present in nearly all foods |
| tay-sachs disease | a genetic disease that principally affects those of Jewish ancestry, marked by an acculation of certain fats in the brain and nerves resulting in brain damage, loss of sign and brain functions |
| down syndrome | a genetic disorder characterized by a broad skull, blunt facial features, short stature, and learning difficulties; caused by the presence of an extra chromosome 21 |
