1. Figure 13.7 Overview of meiosis: how meiosis reduces chromosome number
Interphase
Homologous pair of chromosomes
in diploid parent cell
Chromosomes
replicate
Homologous pair of replicated chromosomes
Sister
chromatids
Diploid cell with
replicated
chromosomes
Figure 13.7 Overview of meiosis: how meiosis reduces chromosome number
Meiosis I 1
Homologous
chromosomes
separate
Haploid cells with
replicated chromosomes
Meiosis II 2
Sister chromatids
separate
Haploid cells with unreplicated chromosomes

2. Prophase I Metaphase I Anaphase I Centrosome (with centriole pair)
Telophase I and
Cytokinesis
Prophase I
Metaphase I
Anaphase I
Centrosome
(with centriole pair)
Sister chromatids
remain attached
Centromere
(with kinetochore)
Sister
chromatids
Chiasmata
Spindle
Metaphase
plate
Figure 13.8 The meiotic division of an animal cell
Cleavage
furrow
Homologous
chromosomes
Homologous
chromosomes
separate
Fragments
of nuclear
envelope
Microtubule
attached to
kinetochore

3. Prophase I Metaphase I Centrosome (with centriole pair) Centromere
(with kinetochore)
Sister
chromatids
Chiasmata
Spindle
Metaphase
plate
Figure 13.8 The meiotic division of an animal cell
Homologous
chromosomes
Fragments
of nuclear
envelope
Microtubule
attached to
kinetochore

4. Telophase I and Cytokinesis
Anaphase I
Sister chromatids
remain attached
Figure 13.8 The meiotic division of an animal cell
Homologous
chromosomes
separate
Cleavage
furrow

5. Telophase II and Cytokinesis
Prophase II
Metaphase II
Anaphase II
Figure 13.8 The meiotic division of an animal cell
Sister chromatids
separate
Haploid daughter cells
forming

6. Prophase II Metaphase II
Figure 13.8 The meiotic division of an animal cell

7. Telephase II and Cytokinesis
Anaphase II
Figure 13.8 The meiotic division of an animal cell
Sister chromatids
separate
Haploid daughter cells
forming

8. Replicated chromosome
MITOSIS
MEIOSIS
MEIOSIS I
Parent cell
Chiasma
Chromosome
replication
Chromosome
replication
Prophase
Prophase I
Homologous
chromosome
pair
2n = 6
Replicated chromosome
Metaphase
Metaphase I
Figure 13.9 A comparison of mitosis and meiosis in diploid cells
Anaphase
Telophase
Anaphase I
Telophase I
Haploid
n = 3
Daughter
cells of
meiosis I 2n 2n
MEIOSIS II
Daughter cells
of mitosis n n n n
Daughter cells of meiosis II

9. Figure 13.9 A comparison of mitosis and meiosis in diploid cells
SUMMARY
Property
Mitosis
Meiosis
DNA
replication
Occurs during interphase before
mitosis begins
Occurs during interphase before meiosis I begins
Number of
divisions
One, including prophase, metaphase,
anaphase, and telophase
Two, each including prophase, metaphase, anaphase, and
telophase
Synapsis of
homologous
chromosomes
Figure 13.9 A comparison of mitosis and meiosis in diploid cells
Does not occur
Occurs during prophase I along with crossing over
between nonsister chromatids; resulting chiasmata
hold pairs together due to sister chromatid cohesion
Number of
daughter cells
and genetic
composition
Two, each diploid (2n) and genetically
identical to the parent cell
Four, each haploid (n), containing half as many chromosomes
as the parent cell; genetically different from the parent
cell and from each other
Role in the
animal body
Enables multicellular adult to arise from
zygote; produces cells for growth, repair,
and, in some species, asexual reproduction
Produces gametes; reduces number of chromosomes by half
and introduces genetic variability among the gametes

10. Possibility 1 Possibility 2 Two equally probable arrangements of
chromosomes at
metaphase I
Figure The independent assortment of homologous chromosomes in meiosis
Metaphase II
Daughter
cells
Combination 1
Combination 2
Combination 3
Combination 4

11. Recombinant chromosomes
Prophase I
of meiosis
Nonsister
chromatids
held together
during synapsis
Pair of
homologs
Chiasma
Centromere
TEM
Figure The results of crossing over during meiosis
Anaphase I
Anaphase II
Daughter
cells
Recombinant chromosomes

13. Animations and Videos Meiosis Tutorial Meiosis - 1 Meiosis - 2
Stages of Meiosis
Anaphase Separase
Spermatogenesis
Production of Male and Female Gametes
Polar Body Formation

14. Animations and Videos Random Orientation of Chromosomes During Meiosis
Independent Assortment
Independent Assortment and Gamete Diversity
Alleles That Do Not Assort Independently
Comparison of Mitosis and Meiosis
Bozeman - Diploid vs. Haploid Cells
Activity- Mitosis and Meiosis
Bozeman - Mitosis and Meiosis Simulation

15. Animations and Videos Meiosis - Nondisjunction – 1
Crossing Over
Changes in Chromosome Structure
The Consequence of Inversion
Bozeman - Cell Cycle (Mitosis and Meiosis)
X Inactivation
Bozeman - X Inactivation

16. Animations and Videos Density-Dependent Inhibition
Cytotoxic T Lymphocytes Attack a Melanoma Cell
Metastasis of a Cancer
Amniocentesis Animation
Chorionic Villus Sampling
Karyotype Animation
Human Melanoma Cells Dividing
Chapter Quiz Questions – 1
Chapter Quiz Questions – 2