cancer Flashcards
what is the definition of benign?
tumour cells that stay in the place where they were formed
what is the definition of malignant?
tumour cells that travel in the blood from where they were formed to other parts of the body where they cause new tumours
what is metastasis?
the migration (movement) of cancer cells to other parts of the body to form new tumours
what does the pronto-oncogene do
?
code for proteins that stimulate cell division and inhibit cell death
what do tumour-suppressor genes do?
code for proteins that prevent cell division or cause cell death
what is cancer?
uncontrolled cell division
what is the threat from benign tumours?
growth compresses other functional body tissues and stops them from working correctly
what is the process of malignant cancer cells spreading called?
metastasis
when does cancer happen?
when mutations occur in the proto-oncogene and tumour suppressor genes
what are oncogenes?
mutated proto-oncogenes that stimulate cell division because the proteins produced from tumour-suppressor genes cannot inhibit the oncogenes.
how can tumour suppressor genes mutate?
so that the protein they produce does not act on proto-oncogenes to inhibit them, therefore cell division continues
why is cancer more likely to occur as you get older?
because more mutations will have occurred
what is chemotherapy?
drugs that affect the cell cycle so that cell division is prevented, or which lead to cell death
what can chemotherapy drugs do?
stop DNA replication
or inhibit mitosis
where are chemotherapy drugs most effective?
against rapidly dividing cells, so cancer cells are more affected than normal cells
what are the side effects of chemotherapy?
drugs affecting normal cells.
rapidly dividing normal cells are more likely to be affected e.g. hair producing cells which therefore leads to atypical hair loss
