CANCER  how does it happen?

Checkpoints  Where a cell Normally checks its self for a mutation as it goes through cell cycle

Checkpoints in cell cycle  G1 – Cell growth -proteins control whether the cell will divide  S – Before DNA Synthesis Check DNA before it replicates  G2 – After DNA synthesis - DNA proofreader enzymes check the DNA and repair  M – Mitosis – mutated cells stopped during mitosis

Cyclins  Proteins that regulate the a cell’s progression through the cell cycle

CANCER –  When cells mutate and grow, by-passing checkpoints

Aptosis  When a mutant cell is destroyed or self destructs after failing check point  Cancer cells do not self destruct and keep multiplying

Cancer cell division  Unlike normal cells, cancer cells continue to divide indefinitely, even if they become densely packed.  Cancer cells will also continue dividing even if they are no longer attached to other cells.

Tumor  A mass of cells that grow uncontrolled

Types of Tumors  Benign = “good” Tumor. NOT cancer Cells grow uncontrollably but DO NOT take over other cells  Malignant = “bad” Tumor. Cancerous Cells invade and take over other cells

Metastasis  A malignant cancer tumor grows and spreads to other parts of body

Carcinogens Any substance that can induce or promote cancer. Examples: Tobacco, certain chemicals, radiation A substances that cause mutations.

 cell cycle and cancer cartoon cell cycle and cancer cartoon