B7- non-communicable diseases 🚬🚭 Flashcards
1
Q
How is a tumour produced ? [3]
A
- cell division by mitosis occurs all over the body, especially during growth and during repair-[e.g- after an injury]
- mitosis is extremely tightly controlled, since genes in the nucleus tell cells when to divide and when to stop dividing.
- ; sometimes changes take place in these genes and that leads to the uncontrolled growth, and mitosis- this produces a tumour.
2
Q
What are the two types of tumours ?
A
- the two types of tumours, are benign and malignant tumours.
3
Q
What are benign tumours ?
A
- benign tumours, are growths of abnormal cells which are found in one area.
- benign tumours are usually contained within a membrane, and benign tumours don’t invade other parts of the body- they stay in one place
4
Q
What are malignant tumours ?
A
- malignant tumors, are tumors which invade neighbouring tissues, and move into the bloodstream.
- once malignant cells are in the bloodstream, the malignant cells can spread to different parts of the body, and form new tumours. [known as secondary tumours]
- they are classified as a cancer.
5
Q
What are the difference between benign tumours 🆚 malignant tumours? [6]
A
- benign tumours, are growths of abnormal cells which are found in one area; with malignant tumours, malignant cells invade neighbouring tissues.
- malignant cells are made of cancerous cells; benign tumours aren’t.
- malignant - malignant cells can also move into the bloodstream; benign tumours don’t.
6
Q
What are the similarities between benign tumours 🆚 malignant tumours? [4]
A
- benign and malignant tumours are made up of abnormal cells and are a result of changes in the genes.
- both tumours can form a lump of cells, and are a result of uncontrolled cell division.
7
Q
What are risk factors for developing cancer ? [4]
A
- some cancers are genetic, and we inherit an increased risk of those cancers from our parents- [e.g- certain types of breast and prostate cancer]
- smoking is a risk factor for lung cancer
- and exposure to ultraviolet lights [e.g- sunbathing], is a risk factor for skin cancer.
- alcohol is a risk factor for mouth, and throat cancer.
8
Q
How are certain cancers linked to substances, in our environment ? [3]
A
- certain cancers linked to substances, in our environment, for example…
- radon, is a radioactive gas which increases your risk of developing lung cancer.
- This is because, radon releasing ionising radiation which damages the DNA in our cells.
- Therefore, this can cause our cells to undergo uncontrolled cell division- leading to cancer.
9
Q
Explain how benign and malignant tumours can be life-threatening.
A
- benign tumours can be life-threatening, if they press against vital organs- [e.g- your brain]
- [malignant] cancer cells can be life-threatning, since they take up the needed space and nutrients that the healthy organs would use.
- And as a result, the healthy organs can no longer function
10
Q
How can a lack of control in the cell cycle to tumour formation ?
A
- a lack of control in the cell cycle to tumour formation,
- because defects in the genes that control the mitotic surveillance mechanism [needed for chromosome sorting], can lead to abnormalities in the number of chromosomes.
- meaning this can lead to the formation of a cancer, when normal cells, are ‘transformed’ into cancerous cells.
11
Q
What is the mitotic surveillance mechanism ?
A
- the mitotic surveillance mechanism, is a pathway preventing the growth of human cells, which will have an increased chance of making errors in mitosis.
12
Q
Compared to communicable, what are most non-communicable diseases caused by ?
A
- unlike how communicable diseases are caused by the spreading of pathogens, non-communicable diseases are caused by risk factors.
13
Q
What is a key fact about correlation ?
A
- correlation doesn’t prove cause.
- For example, a graph of the risk of developing lung cancer, with the number of cigarettes smoked per day, doesn’t prove that cigarette smoking causes lung cancer.
- it only suggests that smoking and lung cancer might be linked.
14
Q
What is a causal mechanism ?
A
- a casual mechanism, is seeing if there is any scientific explanation why something happens.
- it simply means, there’s a link between two factors.
15
Q
What is the casual mechanism for smoking and lung cancer ?
A
- as scientists began to look at how cigarette smoking could cause cancer…
- they discovered that cigarette smoke, contains chemicals which damage DNA, increasing the risk of cancer [known as carcinogens]
16
Q
What are carcinogens ?
A
- carcinogens, are chemicals which damage DNA and increase the risk of cancer.
17
Q
What’s the problem with sampling ?
A
- with sampling, we ideally want to look at every person in the population; it’s not possible to sample every single person.
- so instead, scientists will sample a group of people and then try to draw conclusions about the whole population.
- ; sampling isn’t representative of the whole country, since it can be bias- meaning we can’t use the results, to draw conclusions about the whole population.
18
Q
How could we investigate, how studying the patterns of disease, determines risk factors ?
A
- if we want to investigate how studying the patterns of disease, to determine risk factors, this can pose a problem- sampling.
19
Q
How can we avoid bias in sampling ?
A
- to avoid bias, we need to take as large of a sample as possible, and it it must be as random as possible.
- since we can’t draw conclusions from a small or non-random sample.
21
Q
What is a risk factor ?
A
- a risk factor, is anything that increases a [person’s] chance of developing a disease
21
Q
What is a correlation ?
A
- a correlation, is a relationship between two sets of data- it shows a connection factor and an outcome.
22
Q
What is the difference between a risk factor 🆚 a correlation 🆚 a casual mechanism ? [4]
A
- a risk factor, is anything that increases a [person’s] chance of developing a disease
- a correlation, is a relationship between two sets of data- it shows a connection factor and an outcome.
- a casual mechanism, is seeing if there is any scientific explanation why something happens. [simply means a link bewteen two factors]
23
Q
Explain how the causal link between smoking and lung cancer was identified.
A
- in the 1930s, rates of lung cancer began to sharply increase; scientists couldn’t explain this.
- since it would be unethical to carry out experiments on humans, to try to work out what causes lung cancer..
- scientists began to look very closely at people’s lifestyle habitats- in an to attempt, to link any of these lifestyle habitats to lung cancer.
24
Q
Explain in detail how the causal link between smoking and lung cancer was identified. [4]
A
- as scientists began to look very closely at people’s lifestyle habitats…
- they noticed, that lung cancer is much more common among cigarette smokers, than in non-smokers.
- They then looked at how many cigarettes people smoked each day, and then looked at how of these many people developed lung cancer- they were looking to see, if there was a correlation between lung cancer and smoking.
25
Q
How can scientists determine whether there is a correlation ?
A
- scientists can determine whether there is a correlation, by using a scatter graph.
- from the scatter graph, it showed that as the number of cigarettes smoked per day increases, so did the risk of developing lung cancer.
- after finding a positive correlation, they then plotted a graph of the number of years a person smoked, versus the risk of developing lung cancer- it showed a positive correlation again.
26
Q
When scientists attempted to find a link between smoking and lung cancer, what were the two graphs ?
A
- from the first scatter graph, it showed that as the number of cigarettes smoked per day increases, so did the risk of developing lung cancer.
- after finding a positive correlation, they then plotted a second graph of the number of years a person smoked, versus the risk of developing lung cancer- it showed a positive correlation again.
27
Q
What is epidemiology ? [1]
A
- epidemiology, is studying the pattern of diseases, to determine risk factors.
