Question

In medicine, to destroy cancer cells _______ rays are used.
A) Ultraviolet
B) Visible
C) Gamma
D) Infrared

Answer 1

Hint: Let’s discuss a bit about cancer cells. Cancer cells are cells that divide continually and lead to the formation of solid tumours and flood the body with abnormal cells. Cell division is the process used by the body for growth and repair. A parent cell divides to form two daughter cells, and these daughter cells are used to build new tissue and replace cells that have died because of ageing or damage.

Complete step by step solution:
Cancer cells continue reproducing even when there’s no need for the body to produce new cells, and can spread from one part of the body to another causing severe infections. Radiation therapy, also known as chemotherapy, uses high-energy radiation to shrink tumours and kill cancerous cells; the high energy radiations include X-rays and gamma rays. Gamma rays can also kill living cells and damage malignant tumour, hence are used in very controlled amounts.

The radiation may be delivered from outside the body using external-beam radiation therapy, or it may be delivered by radioactive material placed in the body near cancer cells using internal radiation therapy, also called brachytherapy. Sometimes radioactive iodine is also used to kill cancer cells in the bloodstream.
Hence we can say that gamma rays are used in medicine to destroy cancer cells.

Therefore, the correct option is (C).

Note: Let us discuss the use of other options. Ultraviolet rays can be used to kill microbes; hospitals use ultraviolet lamps to sterilise surgical equipment and the operating theatres. Food and drug companies also make use of ultraviolet rays to sterilise their products. Suitable doses of Ultraviolet rays cause the body to produce vitamin D. One of the most common uses of infrared radiation is in heat-sensitive thermal imaging cameras that are used to study human and animal body heat patterns; they have also been used in warfare, as security cameras and for animal research.