radiation and risk

Question 1

what are tumours?

Answer 1

uncontrolled growth and division, makes abnormal mass of cell

Question 2

what is a benign tumour?

Answer 2

normal group of cells contained in one area, usually membrane (not cancerous)

Question 3

what is a malignant tumour?

Answer 3

spread to different parts of body, forming secondary tumours, causing lots of damage and are fatal(cancer)

Question 4

what increase risk of cancer?

Answer 4

smoking
ultraviolet light exposure
obesity
genes that make us more susceptible

Question 5

what are isotopes?

Answer 5

when there is different number of neutrons in each element, only one being stable, causing radioactive decay

Question 6

what are alpha particles?

Answer 6

made of two protons and neutrons, charge 2+
-cant penetrate well by other materials, absorbed by paper
-strongly ionising
-not travel far

Question 7

what are beta particles?

Answer 7

electron, charge -1,moderatly ionising, moderate penetration
-stopped by thin sheet aluminium

Question 8

What are gamma rays?

Answer 8

waves of electromagnetic radiation, have no mass or charge.
-weakly ionising
-high penetration power, penetrate really far
-stop by thick lead

Question 9

what is half life?

Answer 9

time taken for number of radioactive nuclei in sample to halve. or time taken for the number of decays/activity to halve