High-Energy Radiation Is Often Used to Treat Cancer

Multiple Choice

High-energy radiation is often used to treat cancer.The radiation damages the cancerous cells, and the cell cycle checkpoint for DNA repair is overwhelmed.Radiation therefore

A) causes apoptosis when cells are at the S and G2 checkpoints.
B) inhibits the growth factor at the restriction point.
C) blocks DNA replication.
D) causes apoptosis only at the tumor site.
E) kills all tumor cells without harming healthy cells.