Radiation biology part 1

Question 1

What are the two factors we need to consider to minimise the possibilities of radiation-induced effects?

Answer 1

• Procedural factors
• Biological factors

Question 2

How do biological effects occur at a molecular level

Answer 2

they occur with excitation and ionisation of atoms, and interactions such as the production of free radicals.

Question 3

How do biological effects occur at a cellular level

Answer 3

There is damage to the DNA and chromosomes, which leads to damage of tissues and organs.

Question 4

How do biological effects occur at a whole body level

Answer 4

Responses are identified by early and late effects,

Question 5

What are the two types of radiation interactions?

Answer 5

Direct and Indirect

Question 6

What is the primary target of direct radiation and why

Answer 6

DNA, as it controls the cell’s function and ability to reproduce. And depending on the dosage, radiation can alter the cells characteristics and functions, and ultimately may cause cell death

Question 7

What is the general time for stochastic effects and deterministic effects

Answer 7

1 second to months is deterministic
years to generations is stochastic

Question 8

How long may the expression of cell death take

Answer 8

days to months

Question 9

How long may the expression of carcinogenesis take

Answer 9

Years to generations

Question 10

What is the order of radiobiological damage development, there are 6 steps

Answer 10

1. Incident radiation
2. Radiation absorption
3. Excitation and ionisation
4. Free radical production
5. breaking of chemical bonds
6. Biological effects

Question 11

What are the two radiation effect categories

Answer 11

Deterministic and stochastic

Question 12

Which one is the main concern during fluoroscopic imaging

Answer 12

Deterministic effects

Question 13

What do Deterministic effects mainly depend on

Answer 13

• Dose
• Sensitivity of organ
• Post irradiation time

Question 14

When do early deterministic effects occur, and when do late deterministic effects occur

Answer 14

before 6 months, and after 6 months respectively

Question 15

What are early deterministic effects a result of and are they reversible + an example

Answer 15

Usually a result of cellular damage, and they may be reversible depending on dose type.
- an example is an erythema (skin redness)

Question 16

What are Late deterministic effects a result of and are they reversible + an example

Answer 16

The response is usually a function of the type of healing that occurs in the organ; they are all irreversible, progressive, and permanent.
- an example is cataracts

Question 17

Stochastic effects result from, and an example

Answer 17

They are probabilistic, no threshold dose can happen at any dose at any time, however, the probability of occurrence is proportional to the dose.
- an example is leukaemia