Question

A client's tumor measures 2 cm before and after receiving a course of radiotherapy. What physiological mechanism renders this response to radiation therapy for cancers?

a. Cellular anchorage that is necessary for cancer cell growth is removed.
b. Cell growth is disrupted during the resting phase of the cell cycle.
c. Production of ionizing energy damages DNA, hence stops replication.
d. Reduction of contact inhibition results in cell death by phagocytosis.

Answer 1

The correct option is: c) production of ionizing energy that damages DNA, hence stopping replication. The physiological mechanism that renders the response to radiation therapy in cancer is the production of ionizing energy that damages DNA, stopping replication.

Step-by-step explanation:

Radiotherapy is effective against cancer because cancer cells reproduce rapidly and are more sensitive to radiation. The goal of radiotherapy is to make the dose for cancer cells as high as possible while limiting the dose for normal cells. One of the physiological mechanisms that renders this response to radiation therapy for cancers is the production of ionizing energy that damages DNA, hence stopping replication. The radiation kills cancer cells by affecting their ability to replicate properly.

The correct option is: c) production of ionizing energy that damages DNA, hence stopping replication. The physiological mechanism that renders the response to radiation therapy in cancer is the production of ionizing energy that damages DNA, stopping replication. The radiation kills cancer cells by affecting their ability to replicate properly.