20.5 gene expression and cancer Flashcards Preview

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Flashcards in 20.5 gene expression and cancer Deck (19):
1

compare the size of a benign tumour to a malignant tumour

both grow to a large size

2

compare the speed to growth in a benign tumour to a malignant tumour

benign-> grows slowly
malignant-> grows quickly

3

compare the state of differentiation in benign tumours to malignant tumours

benign-> specialised
malignant-> unspecialised

4

what is metastasis?

process where tumours spread to other parts of the body forming secondary tumours

5

compare the adhesion of the cells in benign tumours and malignant tumours

benign-> adhesion molecule produced so stick together
malignant-> no adhesion molecules so don't stick together

6

compare the presence of a capsule in benign tumours and malignant tumours

benign-> capsule
malignant-> no capsule

7

compare the threat to life benign tumours and malignant tumours have

benign-> not life threatening
malignant-> life threatening

8

compare the effect of the body benign and malignant tumours have

benign-> localised
malignant-> systemic

9

how are benign tumours removed?

surgery

10

how are malignant tumours removed?

radiotherapy, chemotherapy, surgery

11

compare how frequent benign tumours and malignant tumours appear after treatment

benign-> rarely
malignant-> more frequently

12

malignant tumour definition

cancerous tumour

13

benign tumour definition

non- cancerous tumour

14

what are the 2 main type of genes that play a role in cancer?

- oncogenes
- tumour suppressor genes

15

what are oncogenes?

mutated proto-oncogenes

16

what are proto-oncogenes?

genes that stimulate a cell to divide when growth factors attach to a protein cells on its cell surface membrane

17

what happens to proto- oncogenes when growth factors attach to them?

genes are activated which cause DNA to replicate and the cell divides

18

why are oncogenes genes permanently switched on?

- receptor protein can be permanently activated, so that cell division is switched on even if the growth factor is absent
- oncogenes code for a growth factor that is then produced in excessive amounts causing excessive division of cells

19

what are tumour suppressor genes?

genes that slow down cell division, repair mistakes in DNA and 'tell' cells to apoptose