Cell Cycle Cell Growth and Division Animal Cell

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Cell Cycle : Cell Growth and Division Animal Cell Mitosis II

Cell Cycle : Cell Growth and Division Animal Cell Mitosis II

Mitosis

Mitosis

The functions of cell division: Reproduction

The functions of cell division: Reproduction

The functions of cell division: Growth and development

The functions of cell division: Growth and development

The functions of cell division: Tissue renewal

The functions of cell division: Tissue renewal

Eukaryotic chomosomes

Eukaryotic chomosomes

Chromosome duplication and distribution during mitosis Chromosome Coiling video DNA coiled around histone proteins

Chromosome duplication and distribution during mitosis Chromosome Coiling video DNA coiled around histone proteins and condensed into a chromosome

The cell cycle

The cell cycle

The stages of mitotic cell division in an animal cell: G 2 phase; prometaphase

The stages of mitotic cell division in an animal cell: G 2 phase; prometaphase

The stages of mitotic cell division in an animal cell: metaphase; anaphase; telophase and

The stages of mitotic cell division in an animal cell: metaphase; anaphase; telophase and cytokinesis. APC : anaphse promoting complex kinetochores

The mitotic spindle at metaphase

The mitotic spindle at metaphase

Cytokinesis in animal and plant cells video plant cytokinesis video

Cytokinesis in animal and plant cells video plant cytokinesis video

Mitosis

Mitosis

Mitosis in a plant cell

Mitosis in a plant cell

Mitosis in an onion root

Mitosis in an onion root

Bacterial cell division (binary fission) (Layer 1)

Bacterial cell division (binary fission) (Layer 1)

Bacterial cell division (binary fission) (Layer 2)

Bacterial cell division (binary fission) (Layer 2)

Bacterial cell division (binary fission) (Layer 3)

Bacterial cell division (binary fission) (Layer 3)

A hypothesis for the evolution of mitosis

A hypothesis for the evolution of mitosis

Chromosome migration during anaphase

Chromosome migration during anaphase

Evidence for cytoplasmic chemical signals in cell cycle regulation

Evidence for cytoplasmic chemical signals in cell cycle regulation

Mechanical analogy for the cell cycle control system Cdks – cyclin dependant kinase signals/

Mechanical analogy for the cell cycle control system Cdks – cyclin dependant kinase signals/ concentration dependant Cyclin – Fluctuates throughout/ controlling activity of MPF – maturation promoting factor? Phosphorylates kinases that sets off enzymes involved in: digestion of nuclear envelope, chromosome condensation, spindle formation MPF triggers Adult stem cell holding pattern

Molecular control of the cell cycle at the G 2 checkpoint Cdk MPF also

Molecular control of the cell cycle at the G 2 checkpoint Cdk MPF also initiates enzyme for MPF breakdown

MPF Multiple targets, signal amplification, produces a transcription factor that signals a enzyme produced

MPF Multiple targets, signal amplification, produces a transcription factor that signals a enzyme produced to digest the MPF…. eventually turning of the total signal. Mitosis

Internal Signals Checkpoint Control System for Mitosis G 1 – Restriction Point…. . reached….

Internal Signals Checkpoint Control System for Mitosis G 1 – Restriction Point…. . reached…. . go to S…G 2…M Go-ahead signal received GO – Restriction Point…. . Not reached…. . go to GO Nondividing state G 2 End – cyclin high conc. MPF formed, triggers M M – MPF triggers destruction enzymes for MPF, ends mitosis. (Maturation Promoting Factor)

Maturation Promoting Factor • Assembled during G 2 = cyclin + cdks • Causes

Maturation Promoting Factor • Assembled during G 2 = cyclin + cdks • Causes nuclear fragmentation • Phosphorylates protein kinases…. leading to mitosis …… leading to destruction of MPF Skin cells: repeatedly divide Liver cells: divide in response to injury Muscle cells: stay in Go until death, stimulated by PDGF, chemical signal to divide from fibroblasts to produce new cells after injury to site. Nerve cells: reach maturity then stop, new research has found adult stem cells that can produce new cells.

The effect of a platelet derived growth factor on cell division PDGF External Signals

The effect of a platelet derived growth factor on cell division PDGF External Signals Growth factors = mitogen

Fibroblast growth: connective tissue cells

Fibroblast growth: connective tissue cells

Density-dependent inhibition of cell division

Density-dependent inhibition of cell division

The growth and metastasis of a malignant breast tumor

The growth and metastasis of a malignant breast tumor

Breast cancer cell

Breast cancer cell

Mammogram: normal (left) and cancerous (right)

Mammogram: normal (left) and cancerous (right)

From Mitosis to Meiosis • Video: Cell Cycle to Fertilization

From Mitosis to Meiosis • Video: Cell Cycle to Fertilization