A brief yet informative presentation of cell cycle (Mitosis & Meiosis) with nice pictures and gif. Sure students will love it.

2. Overview: The Key Roles of Cell Division
The ability of organisms to reproduce
best distinguishes living things from
nonliving matter
The continuity of life is based on the
reproduction of cells, or cell division
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

3. (a) Reproduction (b) Growth and development
(c) Tissue renewal

4. Phases of the Cell Cycle
The cell cycle consists of
Interphase (cell growth and
copying of chromosomes in
preparation for cell division)
Mitotic (M) phase (mitosis and
cytokinesis)
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

5. Interphase (about 90% of the cell cycle) can
be divided into sub-phases:
G1 phase (“first gap”)
S phase (“synthesis”)
G2 phase (“second gap”)
The cell grows during all three phases, but
chromosomes are duplicated only during the
S phase
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

6. Fig. 12-5
S
(DNA synthesis)
G1
G2

7. Mitosis is conventionally divided into four
phases:
Prophase
Metaphase
Anaphase
Telophase
Cytokinesis is well underway by late telophase
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

8. Structure of Chromosomes
 The centromere is a
constricted region of the
chromosome containing a
specific DNA sequence, to
which is bound 2 discs of
protein called kinetochores.
 Kinetochores serve as points
of attachment for
microtubules that move the
chromosomes during cell
division:
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Metaphase chromosome
Kinetochore
Kinetochore
microtubules
Centromere
region of
chromosome
Sister Chromatids

9. Mitosis and
Meiosis

10. Mitosis and Meiosis
Mitosis:
-division of somatic (body) cells
Meiosis
-division of gametes (sex cells)

11. Interphase
1.Cell preparing to divide
2.Genetic material doubles

12. Prophase
1. Chromosomes thicken and shorten
-become visible
-2 chromatids joined by a centromere
2. Centrioles move to the opposite sides of the
nucleus
3. Nucleolus disappears
4. Nuclear membrane disintegrate

14. Metaphase
 Chromosomes meet in the middle!
1. Chromosomes arrange at equator of cell
2. Become attached to spindle fibres by
centromeres
3. Homologous chromosomes do not associate

16. Anaphase
 Chromosomes get pulled
apart
1. Spindle fibres contract pulling
chromatids to the opposite
poles of the cell

17. Telophase
 Now there are two!
1. Chromosomes uncoil
2. Spindle fibres disintegrate
3. Centrioles replicate
4. Nuclear membrane forms
5. Cell divides

19. Meiosis
4 daughter cells produced
Each daughter cell has half the
chromosomes of the parent
2 sets of cell division involved