Date | May 2018 | Marks available | 2 | Reference code | 18M.3.hl.TZ1.19 |
Level | HL | Paper | 3 | Time zone | TZ1 |
Command term | Describe | Question number | 19 | Adapted from | N/A |
Question
Radiotherapy is one type of treatment for cancer.
Describe how ionizing radiation destroys cancer cells.
Outline how Targeted Alpha Therapy (TAT) is used for treating cancers that have spread throughout the body.
Markscheme
Any two of:
radiation causes breaks in DNA chains
OR
radiation causes errors in DNA sequences
«damage accumulates and» cells cannot multiply
rapidly dividing/cancer cells more susceptible
Accept “alters DNA”.
[2 marks]
Any two of:
radiation source delivered directly to «targeted» cancer cells
by a carrier drug/protein/antibody
several sites in body can be targeted «at same time»
[2 marks]