AP Notes, Outlines, Study Guides, Vocabulary, Practice Exams and more!

Biological Science Freeman Chapter 13 Flashcards

Psu test 3 chapter 13, meiosis.

Terms : Hide Images
5418835313KaryotypeA display of the chromosome pairs of a cell arranged by size and shape.0
5418835314Homologous chromosomesChromosomes that have the same sequence of genes, that have the same structure, and that pair during meiosis.1
5418835315Homologsmembers 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 gene2
5418835316AlleleAlternative forms of a gene for each variation of a trait of an organism.3
5418835317AutosomesAny chromosome that is not a sex chromosome.4
5418835318Reduction divisioncell 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
5418835319Principle of segregationDuring meiosis, chromosome pairs separate into different gametes such that each of the two alleles for a given trait appears in a different gamete.6
5418835320Meiosis(genetics) cell division that produces reproductive cells in sexually reproducing organisms7
5418835321Prophase 1Chromosomes become visible; nuclear envelope breaks down; crossing-over occurs.8
5418835322Crossing-overProcess in which homologous chromosomes exchange portions of their chromatids during meiosis 1.9
5418835323ChiasmaPoint at which chromatids break and rejoin in crossing over.10
5418835324Prometaphase 1The second stage of the first meiotic division (meiosis I), during which the nuclear envelope breaks down, allowing microtubule access to chromosomes.11
5418835325Anaphase 11. Homologous sister chromosomes separate, not individual chromatids.12
5418835326Metaphase 1Paired homologous chromosomes line up across the center of the cell13
5418835327Telophase 1A 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
5418835328Prophase 2Chromatin shortens to chromosomes, spindle appears, nuclear membane disappears; happens in two cells at once. No replication of DNA occurs before Prophase 2.15
5418835329Metaphase 2Centromeres of chromosomes line up randomly at the equator of each cell.16
5418835330Anaphase 2Chromatids are pulled apart resulting in one chomosome from each pair at the equator.17
5418835331Telophase 2A 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
5418835332Independent assortmentOne 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
5418835333Recombination(genetics) a combining of genes or characters different from what they were in the parents.20
5418835334OutcrossingReproduction by fusion of the gametes of different individuals, rather than self-fertilization. Typically refers to plants.21
5418835335Self-fertilizationThe union of sperm and egg from the same individual. (There is still genetic variation, the offspring will be different from the parent.)22
5418835336NondisjunctionError in meiosis in which homologous chromosomes fail to separate. Occurs during Anaphase 1 or 2.23
5418835337MonosomyA condition in a diploid cell in which one chromosome of one pair is missing as a result of nondisjunction during meiosis24
5418835338AneuploidAbnormal number of chromosomes. Either too many or too few.25
5418835339Purifying selectionSelection that lowers the frequency or even eliminates deleterious alleles.26

Need Help?

We hope your visit has been a productive one. If you're having any problems, or would like to give some feedback, we'd love to hear from you.

For general help, questions, and suggestions, try our dedicated support forums.

If you need to contact the Course-Notes.Org web experience team, please use our contact form.

Need Notes?

While we strive to provide the most comprehensive notes for as many high school textbooks as possible, there are certainly going to be some that we miss. Drop us a note and let us know which textbooks you need. Be sure to include which edition of the textbook you are using! If we see enough demand, we'll do whatever we can to get those notes up on the site for you!