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Mitosis – Cellular Division. 30 hours later. 20 hours later. Development of the morula. Blastocyst. 2 types of cells: -cells to become placenta -inner cell mass (stem cells) Stem cells are pluripotent -have ability to read all DNA in their nuclei.
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Blastocyst • 2 types of cells: -cells to become placenta -inner cell mass (stem cells) Stem cells are pluripotent -have ability to read all DNA in their nuclei. -can become any cell In 5 to 6 days lose this ability Blastocyst implants in uterus Photo: NIH
Fig. 13-2b (b) Redwoods
100 µm Fig. 12-2a (a) Reproduction
200 µm Fig. 12-2b (b) Growth and development
20 µm Fig. 12-2c (c) Tissue renewal
0.5 mm Fig. 13-2a Parent Bud Asexual reproduction (a) Hydra
Bacteria Binary fission (asexual reproduction
G1 checkpoint The cell cycle Fig. 12-14 Control system S G1 G2 M M checkpoint G2 checkpoint
G0 G1 checkpoint Fig. 12-15 G1 G1 (b) Cell does not receive a go-ahead signal Cell receives a go-ahead signal
DNA – lots of it in a small space chromosome chromatin
0.5 µm Chromosomes DNA molecules Chromo- some arm Chromosome duplication (including DNA synthesis) Fig. 12-4 Centromere Sister chromatids Separation of sister chromatids Centromere Sister chromatids
INTERPHASE G1 S Cytokinesis Mitosis G2 Fig. 12-UN1 MITOTIC (M) PHASE Prophase Telophase and Cytokinesis Prometaphase Anaphase Metaphase
Fig. 12-20 Lymph vessel Tumor Blood vessel Cancer cell Glandular tissue Metastatic tumor Cancer cells invade neigh- boring tissue. A tumor grows from a single cancer cell. Cancer cells spread to other parts of the body. Cancer cells may survive and establish a new tumor in another part of the body. 4 2 1 3
Fig. 12-3 20 µm
G2 of Interphase Prophase Prometaphase Chromatin (duplicated) Centrosomes (with centriole pairs) Early mitotic spindle Fragments of nuclear envelope Centromere Aster Nonkinetochore microtubules Fig. 12-6b Kinetochore Nuclear envelope Plasma membrane Chromosome, consisting of two sister chromatids Kinetochore microtubule Nucleolus
Telophase and Cytokinesis Metaphase Anaphase Nucleolus forming Metaphase plate Cleavage furrow Fig. 12-6d Daughter chromosomes Nuclear envelope forming Centrosome at one spindle pole Spindle
Aster Centrosome Sister chromatids Microtubules Chromosomes Metaphase plate Fig. 12-7 Kineto- chores Centrosome 1 µm Overlapping nonkinetochore microtubules Kinetochore microtubules 0.5 µm
Nucleus Chromatin condensing 10 µm Fig. 12-10 Chromosomes Cell plate Nucleolus 2 4 1 Prophase Prometaphase 3 Metaphase Anaphase Telophase 5
Fig. 12-9a 100 µm Cleavage furrow Daughter cells Contractile ring of microfilaments (a) Cleavage of an animal cell (SEM)
Fig. 12-9b Vesicles forming cell plate Wall of parent cell 1 µm Cell plate New cell wall Daughter cells (b) Cell plate formation in a plant cell (TEM)
cytokinesis Fig. 12-9 Vesicles forming cell plate Wall of parent cell 1 µm 100 µm Cleavage furrow Cell plate New cell wall Daughter cells Contractile ring of microfilaments Daughter cells (a) Cleavage of an animal cell (SEM) (b) Cell plate formation in a plant cell (TEM)
Fig. 12-UN5 Mitosis video
RESULTS 5 30 4 Fig. 12-16 20 3 % of dividing cells (– ) Protein kinase activity (– ) 2 10 1 0 0 400 100 200 300 500 Time (min)
M M S G1 G1 M G1 S G2 G2 MPF activity Cyclin concentration Fig. 12-17 Time (a) Fluctuation of MPF activity and cyclin concentration during the cell cycle S G1 Cdk Cyclin accumulation M Degraded cyclin G2 G2 Cdk checkpoint Cyclin is degraded Cyclin MPF (b) Molecular mechanisms that help regulate the cell cycle
S G2 M S G2 M G1 M G1 G1 Fig. 12-17a MPF activity Cyclin concentration Time (a) Fluctuation of MPF activity and cyclin concentration during the cell cycle
G1 S Fig. 12-17b Cdk Cyclin accumulation M G2 Degraded cyclin G2 checkpoint Cdk Cyclin is degraded Cyclin MPF (b) Molecular mechanisms that help regulate the cell cycle
APPLICATION Fig. 13-3 TECHNIQUE 5 µm Pair of homologous replicated chromosomes Centromere Sister chromatids Metaphase chromosome
APPLICATION Fig. 13-3a
TECHNIQUE 5 µm Pair of homologous replicated chromosomes Fig. 13-3b Centromere Sister chromatids Metaphase chromosome
Key Maternal set of chromosomes (n = 3) 2n = 6 Paternal set of chromosomes (n = 3) Fig. 13-4 Two sister chromatids of one replicated chromosome Centromere Two nonsister chromatids in a homologous pair Pair of homologous chromosomes (one from each set)
Mitosis – Word BankAsters Centrioles Chromatids Chromosome Cytoplasm Nucleus Nucleolus Nuclear membrane Spindle FibersKinetochore Cleavage Furrow