Campbell Biology Chapter 13

Key Sheet

Gene - Heredity Unit of Information
Gametes - Reproductive Cells
Somatic Cells - All cells aside from Gametes and Precursors
Chromosome - A long DNA chain consisting of few proteins that is used to store 100s to 1000s of genes
Locus - Location of gene along the DNA Sequence of Chromosome
Asexual Reproduction - Reproduction with sole parent, Ends with Clone
Sexual Reproduction - Reproduction with dual parents, Ends with inheritance of both Maternal and Paternal DNA/Chromosomes sets
Karyotype - a form of imaging in which Chromosomes are ordered based of number and organized into pairs
Homologous Chromosomes/Homologs - Two chromosomes of a pair have the same length, centromere position, and staining pattern
X & Y chromosomes - Sex Chromosomes
Autosome - Other Chromosomes aside from sex chromosomes
Diploid Cell - Any cell with 2 sets of chromosomes, 2n
Haploid Cell - Any Cell with 1 set of chromosomes, n
Centromeres - Cellular Structure responsible for organizing chromosomes into order using microtubules
Fertilization - Union of Gametes, usually merging of 2 different gametes
Zygote - Product of Fertilization
Meiosis - Sexual Cell Division, results in 1 set of chromosomes per gamete
Alternation of Generations - Plants and Some Algae perform this type of sexual reproduction resulting in alternation between sporophyte generation and gametophyte generation
Stages of Meiosis - Prophase I, Metaphase I, Anaphase I, Telophase I, Cytokinesis I, Prophase II, Metaphase II, AnaphaseII, Telophase II, Cytokinesis II
Chiasmata - Region of Crossover in Chromosomes
Sister Chromatids - Copy of Individual Chromatid in Chromosomes joined together after S phase
Crossing Over - Process in which regions of non-sister chromatids are broken and rejoined
Non-Sister Chromatids - Chromatids that come from a different set of chromosomes but are equivalent in size, centromere location etc.
Prophase I - Stage where crossing over occurs
Synaptonemal Complex - zipper like complex that holds homologs together
Cohesions - Protein that holds together Sister Chromatids
Synapsis - Process by which Chromosomes cross over
Reasons for Genetic Variation - Independent Assortment, Crossing Over, Random Fertilization
Recombinant Chromosomes - Individual Chromosomes that carry genes from 2 different parents