Ionising Radiation Revision Questions

Question 1

Direct ionising radation

Answer 1

involves ionisning bioogical molecules - e.g point mutations in DNA

Question 2

Indirect ionising radiation

Answer 2

Radiation interacts with water which produces free radicals and combine to form highly reactive speices which cause damage

Question 3

Biological effects depends on

Answer 3

Type of radiation
Amount of radiation
Time over which the dose is recieved
The tissue or cell type irradaited

Question 4

Natural backgrund radiation

Answer 4

Cosmic rays
Internal radionuclides
Radionucleidies in the air
External gamma radation

Question 5

Stochastic effect

Answer 5

By chance and no safe radiation dose - with any does there is a chance that damage will occur
Somatic - effects seens in individual recieving radiation - e.g cancer
Genetic - seen in offspring

Question 6

Determinstic effect

Answer 6

Releated to dose - occur only when thershold does has been reached
Non cancerous but are painful and harmful

Question 7

Absorbed dose

Answer 7

The amount of energy absorbed from beam per unti mass

Question 8

Equivalent dose

Answer 8

Absorbed dose x radiation weighting factors

Takes into account the radiobiological effectiveness of different types of radiation

Question 9

Effective dose

Answer 9

Takes into account the radiosensitivies of different tissues

Question 10

What is the annual radiation dose

Answer 10

2.7mSv

Question 11

Radiation dose for non classified workers

Answer 11

6mSv

Question 12

What factors effect effective dose recieved

Answer 12

area exposed to primary beam
Exposure factors such as low dose
Senstitivity of image recptor