| All genes are located on chromosomes | chromosome theory of inheritance |
| locus | Physical location of a genes |
| heterozygous genotype for the gene at that locus | A diploid cell that has two different alleles at a given genetic locus is a |
| homozygous | A diploid cell that has two identical alleles at a given genetic locus is |
| sex chromosomes vs autosomes | chromosomes that determine sex vs reg chromosomes |
| XX XY | Female chromosomes, vs male |
| a y (male) gene known as: SRY gene | gene that causes other genes located on autosomes to produce male sexual characteristics |
| crossing over | reciprocal exchange of segments of nonsister chromatids in prophase I of meiosis |
| independent assortment of chromosomes | creates new combinations of alleles through the random distribution |
| genetically linked | Genes that are inherited together |
| genetic loci | neighbors or positioned close to each other on the same chromosome |
| pedigree | chart that shows genetic relationships among family members |
| mendelian traits | inherited in a pattern that can predicted on the basis of Mendel’s laws of inheritance. |
| genetic carriers | Individuals that are heterozygous for a recessive disorde |
| sex-linked | Genes found only on the X or Y chromosome are said to be |
| ~ 1,100 | There are ___ X-linked genes in humans; the Y chromosome has very few genes. |
| Males | ____can't be heterozygous for and X-linked genes because Y chromosome does not have a copy of recessive disorders |
| Males | _____are more likely to get recessive X-linked disorders. |
| chromosomal abnormality | change in the number or structure of chromosomes is considered a |
| deletion | when a piece of a chromosome breaks off and is lost. |
| inversion | when a fragment of a chromosome breaks off and returns to the correct place, reverses genetic loci |
| translocation | when a broken piece from one chromosome becomes attached to a different, nonhomologous chromosome. |
| duplication | type of chromosomal abnormality in which a chromosome becomes longer because it ends up with two copies |
| trisomy (down syndrome, Dr John Langdon Down) | when a person inherits three copies of chromosomes 21 |
| Turner syndrome(female phenotype, sterility, short stature), Klinefelter syndrome (mainly male phenotype, tall stature, reduced fertility) | Changes in sex chromosomes: XO, XXY |
