Fig. 13-3b

1
Fig. 13-3b
TECHNIQUE
5 µm
Pair of homologous replicated chromosomes
Centromere
Sister chromatids
Metaphase chromosome
2
Fig. 13-7-1
Interphase
Homologous pair of chromosomes in diploid parent
cell
Chromosomes replicate
Homologous pair of replicated chromosomes
Sister chromatids
Diploid cell with replicated chromosomes
3
Fig. 13-7-2
Interphase
Homologous pair of chromosomes in diploid parent
cell
Chromosomes replicate
Homologous pair of replicated chromosomes
Sister chromatids
Diploid cell with replicated chromosomes
Meiosis I
Homologous chromosomes separate
1
Haploid cells with replicated chromosomes
4
Fig. 13-7-3
Interphase
Homologous pair of chromosomes in diploid parent
cell
Chromosomes replicate
Homologous pair of replicated chromosomes
Sister chromatids
Diploid cell with replicated chromosomes
Meiosis I
Homologous chromosomes separate
1
Haploid cells with replicated chromosomes
Meiosis II
Sister chromatids separate
2
Haploid cells with unreplicated chromosomes
5
Fig. 13-8
Telophase I and Cytokinesis
Telophase II and Cytokinesis
Metaphase I
Prophase II
Metaphase II
Anaphase II
Prophase I
Anaphase I
Centrosome (with centriole pair)
Sister chromatids remain attached
Centromere (with kinetochore)
Sister chromatids
Chiasmata
Spindle
Metaphase plate
Sister chromatids separate
Haploid daughter cells forming
Homologous chromosomes separate
Cleavage furrow
Homologous chromosomes
Fragments of nuclear envelope
Microtubule attached to kinetochore
6
Fig. 13-8a
Telophase I and Cytokinesis
Metaphase I
Prophase I
Anaphase I
Centrosome (with centriole pair)
Sister chromatids remain attached
Centromere (with kinetochore)
Sister chromatids
Chiasmata
Spindle
Metaphase plate
Cleavage furrow
Homologous chromosomes separate
Homologous chromosomes
Microtubule attached to kinetochore
Fragments of nuclear envelope
7
Fig. 13-8b
Prophase I
Metaphase I
Centrosome (with centriole pair)
Centromere (with kinetochore)
Sister chromatids
Chiasmata
Spindle
Metaphase plate
Homologous chromosomes
Fragments of nuclear envelope
Microtubule attached to kinetochore
8
Fig. 13-8c
Telophase I and Cytokinesis
Anaphase I
Sister chromatids remain attached
Cleavage furrow
Homologous chromosomes separate
9
Fig. 13-8d
Telophase II and Cytokinesis
Prophase II
Metaphase II
Anaphase II
Sister chromatids separate
Haploid daughter cells forming
10
Fig. 13-8e
Prophase II
Metaphase II
11
Fig. 13-8f
Telephase II and Cytokinesis
Anaphase II
Sister chromatids separate
Haploid daughter cells forming
12
Fig. 13-11-3
Possibility 2
Possibility 1
Two equally probable arrangements of chromosomes
at metaphase I
Metaphase II
Daughter cells
Combination 1
Combination 2
Combination 3
Combination 4
13
Fig. 13-12-1
Prophase I of meiosis
Nonsister chromatids held together during synapsis
Pair of homologs
14
Fig. 13-12-2
Prophase I of meiosis
Nonsister chromatids held together during synapsis
Pair of homologs
Chiasma
Centromere
TEM
15
Fig. 13-12-3
Prophase I of meiosis
Nonsister chromatids held together during synapsis
Pair of homologs
Chiasma
Centromere
TEM
Anaphase I
16
Fig. 13-12-4
Prophase I of meiosis
Nonsister chromatids held together during synapsis
Pair of homologs
Chiasma
Centromere
TEM
Anaphase I
Anaphase II
17
Fig. 13-12-5
Prophase I of meiosis
Nonsister chromatids held together during synapsis
Pair of homologs
Chiasma
Centromere
TEM
Anaphase I
Anaphase II
Daughter cells
Recombinant chromosomes
18
Fig. 13-5
Key
Haploid gametes (n 23)
Haploid (n)
Egg (n)
Diploid (2n)
Sperm (n)
MEIOSIS
FERTILIZATION
Ovary
Testis
Diploid zygote (2n 46)
Mitosis and development
Multicellular diploid adults (2n 46)
19
Fig. 13-9a
MITOSIS
MEIOSIS
MEIOSIS I
Chiasma
Parent cell
Chromosome replication
Chromosome replication
Prophase I
Prophase
Homologous chromosome pair
2n 6
Replicated chromosome
Metaphase I
Metaphase
Anaphase I
Anaphase Telophase
Telophase I
Haploid n 3
Daughter cells of meiosis I
MEIOSIS II
2n
2n
Daughter cells of mitosis
n
n
n
n
Daughter cells of meiosis II
20
Fig. 13-9b
SUMMARY
Meiosis
Mitosis
Property
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
Occurs during prophase I along with crossing
over between nonsister chromatids resulting
chiasmata hold pairs together due to sister
chromatid cohesion
Synapsis of homologous chromosomes
Does not occur
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