| A | B |
|---|
| autosome | a chromosome that is not a sex chromosome |
| chromosome | a thread-like structure made of molecules within the nucleus that contains genetic information that is passed from one generation to the next |
| gene | a sequence of DNA that codes for/determines a specific trait |
| karyotype | a picture of the complete diploid set of chromosomes grouped together in pairs, arranged in order of decreasing size |
| pedigree | chart that shows the presence or absence of a trait according to the relationships within a family across several generations |
| sex chromosome | one of the 2 chromosomes which determine an individual's sex (XX or XY) |
| congenital disorder | a disorder that a person is born with |
| a disorder that is caused by a defect associated with one or both of a person's sex chromosomes (X and/or Y) | sex-linked disorder |
| autosomal disorder | a disorder that is caused by a problem related to an autosomal chromosome (non-sex chromosome) |
| 22 | number of autosomal pairs of chromosomes in a human |
| 1 | number of pairs of sex chromosomes in a human |
| sex-linked gene | A gene located on the sex chromosome (either x or y) |
| non-disjunction | Failure of a chromosome pair to separate correctly during meiosis |
| trisomy | A condition that happens when cells contain too many copies of a chromosome (3 instead of just 2 copies) |
| amniocentesis | A prenatal technique that involves withdrawing a small amount of fluid from the sac surrounding the fetus |
| CVS (chorionic villus sampling) | A prenatal technique that involves the removal and examination of tissue surrounding the fetus |
| barr body | the inactive X chromosome in a female somatic cell |
| Tay-Sachs disease | a deadly disease of the nervous system caused by one missing base pair of a chromosome, which causes fat to build up in the brain, passed down through families (recessive) |
| Mary Lyon - 1961 | First person to identify the inactivated X in female somatic cells |
| chromosomal number disorder | A genetic disorder caused by the presence of too many or too few chromosomes in a person's/organism's cells |
| example of a sex-linked chromosome number disorder | Klinefelter's disorder |
| examples of sex-linked disorders | Colorblindness, Hemophilia |
| examples of autosomal disorders | Huntington's disease, Cystic Fibrosis, Tay Sach's disease, Sickle Cell disease |
| examples of autosomal trisomy disorders | Edward's syndrome, Down Syndrome |
| Sickle-cell disease | a recessive autosomal disorder caused by a defective protein that causes blood cells to be misshapen |
| Cystic Fibrosis | a recessive autosomal disorder caused by a missing amino acid in the protein that helps with the normal passage of chloride ions across the cell membrane of cells - leads to build up of mucous which clogs lungs/airways |
| Huntington's disease | a dominante autosomal disorder caused by a repeating codon (CAG sequence) which makes an ineffective protein in brain cells that causes neurological deterioration beginning around age 30-40 yrs of age |
| dominant autosomal disorder | one copy of the "bad" gene can cause the person to have the disorder |
| recessive autosomal disorder | two copies of the "bad" gene are needed to cause the person to have the disorder |
| carrier | a person who has one "bad" copy of a particular disorder on one of their chromosomes (not on both chroms of the same set) |
| Down Syndrome | also known as Trisomy 21 |
