| A | B |
|---|
| diploid | a cell with two of each kind of chromosome (2n) |
| haploid | cell with one of each type of chromosome |
| homologous chromosome | paired chromosome with genes for the same traits |
| meiosis | cell division occuring in gamete producing cells that produces four gametes with half the original number of chromosomes |
| sperm | haploid male sex cells |
| egg | haploid female sex cells |
| zygote | diploid cell formed when a sperm fertilizes an egg |
| sexual reproduction | reproduction that involves combining genetic material from two individuals |
| crossing over | exchange of genetic material between nonsister chromatids of homologous chromosomes |
| genetic recombination | source of genetic variation cause by reassortment or crossing over during meiosis |
| nondisjunction | gametes with too many or too few chromosomes due to failure of chromosomes to separate correctly during meiosis |
| prophase I | phase of meiosis I when crossing over takes place |
| metaphase I | phase of meiosis I when tetrads line up at the equator of the cell |
| anaphase I | phase of meiosis I where homologous pairs are pulled to opposite sides of the cell |
| telophase I | phase of meiosis I where two cells with half the genetic material of the original cell are created |
| meiosis II | second set of phases much like mitosis that results in four haploid cells containing one chromosome from each homologous pair |
