BIO-1201 Study Guide - Final Guide: Interphase, Meiosis, Centromere
Document Summary
Meiosis serves 2 major functions: reducing chromosome number, shuffling chromosomes in the cell to produce genetically different gametes. Homologous chromosomes: members of a pair of chromosomes, also called homologous, have the same size, shape, and construction (location of centromere, contain the same genes for the same traits. Homologous pairs may contain different versions of the same gene: alleles alternate forms of a gene. Meiosis 1: homologous pairs line up during synapsis resulting in tetrad, homologous chromosomes of each pair then separate. Meiosis 2: no duplication of chromosomes (no interphase, chromosomes are dyads composed of two sister chromatids, sister chromatids are separated, two daughter nuclei separate. Crossing over: during prophase 1, homologous chromosomes pair up and form a tetrad. This process is called synapsis: each tetrad consists of two chromosomes, with each chromosome containing two chromatids, for a total of four chromatids, when a tetrad forms during synapsis, chromatids from homologous chromosomes may exchange genetic material.