0801 cell cycle
Upcoming SlideShare
Loading in...5

0801 cell cycle



IBSL/IBHL Biology chapter/topic 2.5

IBSL/IBHL Biology chapter/topic 2.5



Total Views
Views on SlideShare
Embed Views



1 Embed 30

https://jujo00obo2o234ungd3t8qjfcjrs3o6k-a-sites-opensocial.googleusercontent.com 30



Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
Post Comment
Edit your comment

0801 cell cycle 0801 cell cycle Presentation Transcript

  • Mitosis and the Cell Cycle
  • Why is mitotic cell division necessary?
    • 1. Asexual reproduction : ex: bacteria (binary fission)
    • 2. To replace damaged or dead cells
    • 3. Growth and embryonic development of the organism
    dividing bone marrow cells  new blood cells Sand dollar embryo Amoeba reproducing
  • Binary Fission: how some bacteria reproduce
  • frog embryo
  • Phases of Mitosis
    • Interphase (NOT PART OF MITOSIS)
    • Chromatin has already duplicated (DNA replication complete) but is not visible to naked eye
    • Early prophase :
    • Spindle microtubules are growing
    • Chromatin condenses and is packed into discrete chromosomes
    • Late prophase :
    • Each chromosome consists of two identical chromatids formed by DNA replication in interphase and held together by a centromere
    • Spindle microtubules extend from each pole to the equator
    • Prometaphase:
    • nuclear envelope disappears
    • spindle microtubules attach to sister chromatids
    • Metaphase:
    • sister chromatids line up on the metaphase plate
    • mitotic spindle forms
    • Anaphase:
    • centromeres split, sister chromatids separate and each one is pulled to opposite ends of the cell
    • cell begins to lengthen
    • by the end of anaphase, there are 2 complete sets of genetic material at each pole
    • Telophase:
    • nuclear envelope starts to reappear
    • microtubule assembly starts to disintegrate
    • chromatids begin to loosen
    • Cytokinesis:
    • The cell divides to form 2 cells with genetically identical nuclei
  • Animal Cell Division
  • Plant Cell Division
  • eukaryotic chromosomes (orange) in a kangaroo rat epithelial cell
  • Differences in Cell Division Between Plant and Animal Cells
  • Differences in Cell Division Between Plant and Animal Cells
    • Plant Cells
      • There are no centrioles in plant cells
      • After anaphase, a new cell wall is formed across the equator of the cell, with plasma membrane on both sides. This divides the cell into two cells
    • Animal Cells
      • Centrioles are found at each pole of animal cells during mitosis
      • After anaphase, the plasma membrane at the equator is pulled inwards until it meets in the center of the cell, dividing it into two cells
  • cell plate: dividing plant cell
  • onion root tip: lots of dividing cells