Bio Notes 3-2-2016
Bio Notes 3-2-2016 BIOL 1014
Popular in Life: Continuity and Change
Popular in Biology
verified elite notetaker
This 2 page Class Notes was uploaded by Crystal Florman on Thursday March 3, 2016. The Class Notes belongs to BIOL 1014 at University of Northern Iowa taught by Dr. Kurt Pontasch in Spring 2016. Since its upload, it has received 44 views. For similar materials see Life: Continuity and Change in Biology at University of Northern Iowa.
Reviews for Bio Notes 3-2-2016
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 03/03/16
Life: Continuity and Change Lecture 3-2-2016 Mitosis Importance of cell division o Insures that organisms can increase in size, start off with one cell and now have several trillion cells, dead cells are replaced with new ones (1 million per second), damaged tissues can be repaired o Cell division has two events Mitosis- the distribution of parent DNA into 2 new daughter nuclei Cytokinesis- division of cytoplasm o Cell cycle- all cells have a cycle, but vary in the amount of time spent in each stage Eukaryote cells have 4 stages: G1, S, G2, Cell Division (CD) G1- cell grows in volume as it produces tRNA, mRNA, and ribosomes and other cell components S- DNA replication occurs in preparation for the distribution of genes to the daughter cells G2- spindle fiber proteins are formed in preparation for mitosis CD- both mitosis and cytokinesis Interphase- time spent between cell divisions o Nuclear membrane is intact, chromosomes are not visible, and the cell is going about its normal metabolic activity Stages of Mitosis 4 stages of mitosis o Prophase As the G2 stage of interphase ends this begins Thin coils of chromatin tighten and become visible as chromosomes Soon we see that each chromosomes are made up of 2 parallel threads called chromatids Chromatids were formed during the S stage of interphase when the DNA was replicated- held together by the centromere Centrioles begin to move to the opposite sides of the cell- as they move microtubules form a spindle that extends between them By the end of prophase the nuclear membrane and the nucleolus have disappeared o Metaphase Chromosomes become attached to the spindle fibers at their centromeres Line up along the equatorial plain At this point each chromosome consists of 2 chromatids Humans have 23 pairs of homologous chromosomes- 46 chromosomes- 92 chromatids o Anaphase Chromosomes split at the centromere and the chromatids move along the spindle fibers towards the poles Chromatids now called daughter chromosomes- identical genetic info End- 2 identical sets of chromosomes at the poles- cytokinesis begins o Telophase Groups of chromosomes at each pole become surrounded by a nuclear membrane Spindle fibers disintegrate- centrioles replicated- mitosis is over Cell still hasn’t split o After telophase the second step in CD (cytokinesis) is complete Mitosis- Plant and animal differences o Plants lack centrioles but still produce spindle fibers o Animal cytokinesis involves a cleavage furrow- plant involves a cell plate which forms at the cell center and moves outward to divide the cell
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'