HSCI 100 Lecture Notes - Lecture 3: Sister Chromatids, Spindle Apparatus, Nuclear Membrane

• School: Simon Fraser University
• Department: Health Sciences
• Course: HSCI 100
• Professor: Nienke Van Houten

Document Summary

Chromosomes tightly coiled combination of a dna molecule that contains genetic info for the organism and specialized proteins called histones. 1 of 23 = sex chromosomes, 22 others = autosomes (expression of most ppl inherited characteristics) Gene: specific segment of the dna that directs synthesis of a protein. Diploid (2n) 2 copies of each chromosome. Haploid (n) one copy of each chromosome. Division: mitosis what somatic/germ cells do, meiosis only what germ cells do. G1 stage growth: cell grows in size & accumulates materials, proteins needed for dna replication are synthesized, each chromosome has dna molecule &proteins. S stage dna synthesis (replication: dna replication occurs, copy of each chromosome (sister chromatids, chromosome copies remain attached. G2 stage growth: proteins needed for division are synthesized (microtubules/centrioles, cell division (mitosis & cytokinesis) Mitosis nuclear division (separation of chromatids) 2 identical daughter cells: functions: Responsible for cell replacement, growth & development.