1. The Biology of Cancer (pg 12)

2. The Biology of Cancer (pg 12)
• Cancer = uncontrolled cell division

3. The Biology of Cancer (pg 12)
• Cancer = uncontrolled cell division
• Cells divide through a process called mitosis

4. The Biology of Cancer (pg 12)
• Cancer = uncontrolled cell division
• Cells divide through a process called mitosis
• Normally, cells undergo mitosis only when
necessary (to replace old cells, during growth,
etc.)

5. The Biology of Cancer (pg 12)
• Cancer = uncontrolled cell division
• Cells divide through a process called mitosis
• Normally, cells undergo mitosis only when
necessary (to replace old cells, during growth,
etc.)
• In cancer, cells divide constantly, forming a
large mass (tumor) that disrupts other organs

6. Mutations and Cancer
• There are multiple genes that serve as
“checkpoints” that prevent cells from dividing

7. Mutations and Cancer
• There are multiple genes that serve as
“checkpoints” that prevent cells from dividing
• Over time, people accumulate mutations in
their DNA from copying errors and mutagens

8. Mutations and Cancer
• There are multiple genes that serve as
“checkpoints” that prevent cells from dividing
• Over time, people accumulate mutations in
their DNA from copying errors and mutagens
• If a person develops mutations in all of the
“checkpoint” genes then they will get cancer

9. Mutations and Cancer
• There are multiple genes that serve as
“checkpoints” that prevent cells from dividing
• Over time, people accumulate mutations in
their DNA from copying errors and mutagens
• If a person develops mutations in all of the
“checkpoint” genes then they will get cancer
• Therefore, cancer is more common in older
people (children with cancer often have
defective “proofreading” enzymes)