Psu test 3 chapter 13, meiosis.
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| 5418835313 | Karyotype | A display of the chromosome pairs of a cell arranged by size and shape. | 0 | |
| 5418835314 | Homologous chromosomes | Chromosomes that have the same sequence of genes, that have the same structure, and that pair during meiosis. | 1 | |
| 5418835315 | Homologs | members of each diploid pair - one from mother and one from father. Similar in size, banding pattern, and have similar composition of genetic material but may carry different alleles of same gene | 2 | |
| 5418835316 | Allele | Alternative forms of a gene for each variation of a trait of an organism. | 3 | |
| 5418835317 | Autosomes | Any chromosome that is not a sex chromosome. | 4 | |
| 5418835318 | Reduction division | cell division that produces reproductive cells in sexually reproducing organisms; the nucleus divides into four nuclei each containing half the chromosome number (leading to gametes in animals and spores in plants). | 5 | |
| 5418835319 | Principle of segregation | During meiosis, chromosome pairs separate into different gametes such that each of the two alleles for a given trait appears in a different gamete. | 6 | |
| 5418835320 | Meiosis | (genetics) cell division that produces reproductive cells in sexually reproducing organisms | 7 | |
| 5418835321 | Prophase 1 | Chromosomes become visible; nuclear envelope breaks down; crossing-over occurs. | 8 | |
| 5418835322 | Crossing-over | Process in which homologous chromosomes exchange portions of their chromatids during meiosis 1. | 9 | |
| 5418835323 | Chiasma | Point at which chromatids break and rejoin in crossing over. | 10 | |
| 5418835324 | Prometaphase 1 | The second stage of the first meiotic division (meiosis I), during which the nuclear envelope breaks down, allowing microtubule access to chromosomes. | 11 | |
| 5418835325 | Anaphase 1 | 1. Homologous sister chromosomes separate, not individual chromatids. | 12 | |
| 5418835326 | Metaphase 1 | Paired homologous chromosomes line up across the center of the cell | 13 | |
| 5418835327 | Telophase 1 | A nuclear membrane forms around each cluster of chromosomes. Cytokinesis then occurs, resulting in two new cells. The resulting daughter cells contain chromosomes sets that are different from each other and the parent cell. (Results in 2 2n diploid daughter cells) | 14 | |
| 5418835328 | Prophase 2 | Chromatin shortens to chromosomes, spindle appears, nuclear membane disappears; happens in two cells at once. No replication of DNA occurs before Prophase 2. | 15 | |
| 5418835329 | Metaphase 2 | Centromeres of chromosomes line up randomly at the equator of each cell. | 16 | |
| 5418835330 | Anaphase 2 | Chromatids are pulled apart resulting in one chomosome from each pair at the equator. | 17 | |
| 5418835331 | Telophase 2 | A nuclear membrane forms around each set of chromatids and the cytoplasm divides. Each nucleus has n chromosomes (haploid). (Results in 4 haploid daughter cells, each genetically different from each other and their parent cells.) | 18 | |
| 5418835332 | Independent assortment | One of Mendel's principles that states that genes for different traits can segregate independently during the formation of gametes. (They are on different chromosomes) | 19 | |
| 5418835333 | Recombination | (genetics) a combining of genes or characters different from what they were in the parents. | 20 | |
| 5418835334 | Outcrossing | Reproduction by fusion of the gametes of different individuals, rather than self-fertilization. Typically refers to plants. | 21 | |
| 5418835335 | Self-fertilization | The union of sperm and egg from the same individual. (There is still genetic variation, the offspring will be different from the parent.) | 22 | |
| 5418835336 | Nondisjunction | Error in meiosis in which homologous chromosomes fail to separate. Occurs during Anaphase 1 or 2. | 23 | |
| 5418835337 | Monosomy | A condition in a diploid cell in which one chromosome of one pair is missing as a result of nondisjunction during meiosis | 24 | |
| 5418835338 | Aneuploid | Abnormal number of chromosomes. Either too many or too few. | 25 | |
| 5418835339 | Purifying selection | Selection that lowers the frequency or even eliminates deleterious alleles. | 26 |
