Binary Fission:• Cell Division in Prokaryotic Cells• asexual reproduction in which one cell divides

into two identical daughter cells

The Cell Cycle

How cells divide to make new cells

Just like people have phases of development,

Cells have phases too.

In somatic (body) cells, a parent cell

produces 2 daughter cells.

The purpose of cell division is for growth and repair

of tissue.

Three Phases or Stages

1. Interphase2. Mitosis3. Cytokinesis

Interphase

Interphase DNA and organelles replicate Cell spends most of its life in

this stage

Stages of InterphaseG1 (growth) normal activities – endo & exo

S (synthesis) genetic material is duplicated so each daughter cell contains the same amount of genetic material as the parent cell

G2 (growth) preparing for cell division

Mitosis

Nucleus divides Duplicated DNA is divided

into two new nuclei

Stages of Mitosis

ProphaseMetaphaseAnaphaseTelophase

Prophase

Prophase

• Nuclear membrane breaks down• Genetic material (chromatin)

condenses• Centrioles migrate to opposite

ends of poles (in animal cells)•Microtubules (spindle fibers)

attach to centrioles

Prophase

Metaphase

Metaphase

• Duplicated chromosomes line up on the equator of the cell

• Microtubules (spindle fibers) attach to centromere at kinetochore

Metaphase

Anaphase

Anaphase

• Duplicated chromosomes (also called sister chromotids) separate

• 1 of each pair are pulled apart toward opposite poles of the cell

Anaphase

Telophase

Telophase

• New nuclear membranes form to separate the genetic material

• Cleavage furrow in animal cells

• Cell plate in plant cells

Telophase

Mitosis

Cytokinesis

Cytokinesis

• Occurs AFTER telophase and BEFORE interphase

• Cytoplasm divides

Cytokinesis

Mitosis Animation

What happens when cells divide at an uncontrollable rate?

CANCER

Causes of Cancer

• Tobacco•Radiation exposure•Viral infections (HPV)•Genetics

Cancer Animation