Cell Division

Why is Cell Division Important??

DNADeoxyribonucleic Acid

What is Deoxyribonucleic Acid?

Long thin molecule that stores genetic informationResponsible for the inheritance of traits.

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ChromosomesDNA coils into structures called CHROMOSOMES during cell division

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Chromosomes

CHROMATIDCENTROMERE

I’m a Chromosome!!

Chromosome typesHuman chromosomes are arranged into two types

SEX CHROMOSOMES – determine sex of individual (X,Y)

All other chromosomes are called AUTOSOMES

Diploid Cells•Most cells in your body are somatic•Contain 2 of each chromosome (this is the diploid number)

•46 total•23 homologous pairs

BINARY FISSION• Prokaryotic

cells– bacteria

Cell Division is a process where new body cells are made

• And the new cells (daughter cells) are identical to the parent cells

• How…and…Why???

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MITOSISIntelligent People Meet At Three

O’Clock”• INTERPHASE

• PROPHASE• METAPHASE• ANAPHASE

• TELOPHASE• CYTOKINESIS

The Cell Cycle

• INTERPHASE– Time between cell divisions

• MITOSIS– Nucleus of cell divides

• CYTOKINESIS– Division of cytoplasm of cell

INTERPHASE

• G1-cells grow

• S-DNA duplicateS

• G2-cell prepares for division

• G0-cells exit cycle-quit growing

PROPHASE• DNA coils into

chromosomes

• Centrosomes appear– will later give out

spindle fibers

• Nuclear envelope disappears

METAPHASE• Chromosomes

line up along middle of cell by the spindle fibers attached to centromeres

ANAPHASE• Chromosomes

separate and move toward opposite poles of dividing cell

TELOPHASE• Chromosomes reach opposite ends of cell

• Chromosomes decondense

• Membrane starts to form

CYTOKINESIS• Cytoplasm of cell

divides

• Cell membrane pinches inward

Metaphase

Interphase

Prophase

Telophase

Anaphase

• 2 new things you learned today…

• Questions you still have…

• What information do you still need that you are missing?

• What still doesn’t make sense?

• Something else you would like to talk about that is related.