Question

Define multihit hypothesis. INCLUDE THE FOLLOWING:

• a: Define the term “hit”
• b: Define how many hits normally will cause a cell to become cancer.
• c: Explain the type of cell that normally becomes a cancer cell and WHY.
• d: Explain the importance of time in a cell becoming a cancer cell.

Answer 1

Multihit hypothesis also known as Knudson's two hit hypothesis.

A) The two hits are the genetic damage and environmental exposure. First hit is generic damage and second hit is environmental exposure.

B) Cells need two hits to become cancerous. First us genetic and second is environmental.

C) Cells that actively divide like haemotopoetic cells are at more risk of developing cancer. This is because of higher probability of getting genetic mutations.

D) If the environmental damage occurs during DNA replication phase of cell cycle, the risk of developing cancer is increased.