Topic 8A: Cancers Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

How does cancers occur?

A

When mutation in genes cause an uncontrollable cell growth. This eventually forms tumours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are acquired mutations?

A

Mutations that occur in the individual cells after fertilisation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What causes uncontrolled cell divisions?

A

When the mutations occur in the genes that control the rate of cell division

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are tumours?

A

-a mass of abnormal cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How do you know the tumours are cancerous?

A

they invade and destroy surrounding tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Name the types of genes that control cell division

A
  • tumour suppressor genes

- proto-oncogenes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What do tumour suppressor genes do when they function normally?

A
  • they slow cell division by
  • producing proteins that stop cells dividing
  • or cause them to self destruct (apoptosis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What happens if the tumour suppressor genes are mutated in the DNA sequence?

A
  • the genes get inactivated
  • the protein to stop cells dividing isn’t produced
  • therefore cells divide uncontrollably
  • rate of cell division increases
  • results in a tumour
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What do proto-oncogenes genes do when they function normally?

A
  • the genes stimulate cell division

- by producing proteins that make cells divide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What happens if the proto-oncogenes genes are mutated in the DNA sequence?

A
  • the effect of proto oncogenes are increased
  • gene becomes overeactive
  • stimulates cells to divide uncontrollably
  • rate of cell division increases
  • results in a tumour
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What do you call a mutated proto oncogene?

A

oncogene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the two types of tumours?

A

Benign

Malignant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are benign tumours?

A
  • non cancerous tumours
  • grow slower than malignant tumours
  • often covered in fibrous tissue which stops cells invading other tissues
  • can cause blockage and put pressure on organs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Can benign tumours turn into malignant?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are malignant tumours?

A
  • cancerous tumours
  • grow rapidly
  • invade and destroy surrounding tissues
  • cells can break off the tumours and spread to other parts
  • like bloodstream/lymphatic system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How do tumour cells looks different to normal cells?

A
  • irregular shape
  • nucleus larger and darker
  • sometimes more than one nucleus
  • dont produce all the proteins needed
  • different antigens on their surface
  • they don’t respond to growth regulating processes
  • divide more frequently
17
Q

What is methylation?

A

adding a methyl group on something

18
Q

Why is the methylation of DNA important?

A

Because it ca control whether or not a gene is transcribed (copied into mRNA) and translated (turned into protein)

19
Q

Abnormal methylation caused by

A

growht of tumours

20
Q

Tumour suppressor genes are….

A

HypERmethylated

21
Q

Proto oncogenes are

A

HypOmethylated

22
Q

What does hypermethylated tumour suppressor gene leads to?

A
  • genes not transcribed
  • proteins to slow cell division is not made
  • cells divide uncontrollably by mitosis
23
Q

What does hypormethylated proto oncogene gene leads to?

A
  • act as oncogenes

- increases production of proteins for cells to divide

24
Q

Increased exposure to oestrogen can….

A

increase a woman’s risk of developing breast cancer

25
Q

What causes the increase exposure to oestrogen?

A
  • starting menstruation early than usual
  • starting menopause later than usual
  • result in taking oestrogen containing drugs such as HRT
26
Q

Outline theories on how oestrogen contribute to the development of some breast cancer…

A

1) -oestrogen can stimulate certain breast cells to divide and replicate
- the more cell divisions can increase the chance of cells becoming cancerous
2) oestrogen maybe actually able to introduce mutations directly into the DNA of certain breast cells.
- increase the chance of these cells becoming cancerous