OCR Gateway Science Additional B Higher- P4-Treatment

Which type of radiation has no use in medicine and why?

Alpha because its absorbed by the skin

Which type of radiation has limited uses in medicine and why?

Beta because it passes through skin but not bone

Which type of nuclear radiation is widely used in medicine and why?

Gamma because it is very penetrating and can be used to kill cancer cells

Common properties of x rays and gamma rays?

Both very high frequency, both electromagnetic waves, both ionising, both used in medicine for diagnosis and treatment, both similar wavelengths and both penetrating

How are x rays produced?

Firing high speed electrons at a metal target- kinetic energy of electrons converted to x rays when they hit the metal target

How are gamma rays produced?

Nuclear decay

Advantages of x rays over gamma rays?

Can produce x rays when needed, can control how fast x rays are produced, can control the energy of the x rays by increasing or decreasing voltage of machine

Why are neutrons absorbed easily by nuclei?

They move slowly

What radioisotope is often used to treat cancer?

Cobalt 60

How is damage to healthy cells limited during radiotherapy?

A wide beam of gamma rays are focused on the tumor. The beam is rotated around the body with the tumor at the centre of rotation and gamma rays are concentrated on the tumor and other cells and not damaged much OR…