non-communicable diseases Flashcards

bbc bitesize

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

alcohol

definition

A

A depressant that can be found in wines, spirits and beers. Also known as ethanol.

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

alloy

definition

A

An alloy is a mixture of two or more elements, at least one of which is a metal.

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

alveoli

definition

A

Tiny air sacs in the lungs, where gas is exchanged during breathing.

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

Alzheimer’s disease

definition

A

A disease in which the brain degenerates and short term memory is lost.

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

What are arteries?

A

Blood vessels that carry blood away from the heart.

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

What is blood pressure?

A

The force of blood against the artery walls.

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

What are bronchioles?

A

The many small, branching tubules into which the bronchi subdivide.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

bronchitis

definition

A

Inflammation of the bronchi and bronchioles.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

cancer

definition

A

A disease caused by normal cells changing so that they grow and divide in an uncontrolled way. The uncontrolled growth causes a lump called a tumour to form.

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

What is carbon monoxide?

A

Poisonous gas produced during incomplete combustion.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What does cardiovascular mean?

A

Relating to the heart and the blood vessels.

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

What is the cervix?

A

Ring of muscle at the lower end of the uterus.

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

chemotherapy

definition

A

The use of chemicals to treat cancer. The chemicals used are highly toxic to cells that divide rapidly.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

cholesterol

definition

A

A type of lipid (fatty substance).

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

What is cirrhosis?

A

Scarring of the liver, which can be caused by alcoholism or hepatitis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is a clot?

A

A clump of platelets and blood cells that forms when a blood vessel is damaged.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is COPD?

A

COPD or chronic obstructive pulmonary disease is the name to several lung diseases that restrict air flow in the lungs and cause breathing difficulties for a patient.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What does coronary mean?

A

Referring to the heart and the blood vessels which serve the heart tissues.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

coronary heart disease

definition

A

A form of heart disease in which one or more of the coronary arteries become blocked, depriving the heart muscle of oxygen.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

correlation

definition

A

A relationship between two sets of data, such that when one set changes you would expect the other set to change as well.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

diabetes

definition

A

A serious disease in which the body is unable to regulate blood sugar.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is a donor?

A

A person or organism providing an organ or tissue for transplant.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

element

definition

A

A substance made of one type of atom only.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is emphysema?

A

Disease in which the walls of the alveoli break down, reducing the surface area for gas exchange in the lungs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

epidemiology

definition

A

The study of the distribution and patterns of health and disease.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is a heart attack?

A

When the supply of blood to the heart is suddenly blocked.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

heart disease

definition

A

A wide range of conditions that affect the heart.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

heart faliure

definition

A

A condition where the heart is failing to pump sufficient blood around the body at the appropriate pressure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is a heart transplant?

A

An operation to replace a damaged heart with a healthy heart from a donor.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is hepatitis?

A

Inflammation or swelling of the liver, for example because of infection by a virus or drinking too much alcohol.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is a histogram?

A

A graphical representation of the distribution of numerical data.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

immune system

definition

A

The body’s defence system against entry of any foreign body, including pathogens and agents such as pollen grains. The role of the immune system is to prevent disease.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

immunosuppressant drug

definition

A

A type of drug that prevents a patient’s immune system from rejecting a transplant.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is insulin?

A

A hormone that regulates the level of sugar in the blood and can be produced by genetically modified bacteria.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

ionising radiation

definition

A

Radiation that is able to remove electrons from atoms or molecules to produce positively charged particles called ions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

lipid

definition

A

Fat or oils, composed of fatty acids and glycerol.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What is the liver?

A

The large organ, beside the stomach, which has many functions, including processing substances absorbed by the digestive system and a role in the storage of the body’s carbohydrate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

monoclonal antibody

definition

A

Identical copies of an antibody produced by fusing a spleen cell with a cancerous white blood cell which can be designed to bind to many different substances.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

mucus

definition

A

Slimy white protein, which lines the respiratory tract and alimentary canal.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

neurological

meaning

A

To do with the nervous system.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What is nicotine?

A

The addictive substance found in tobacco and tobacco smoke.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

non-communicable disease

definition

A

A disease that is not transferred between people or other organisms.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

obesity

definition

A

The medical term for being very overweight, owing to the excessive accumulation of body fat.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

organ

definition

A

A group of different tissues that work together to carry out a particular function, eg heart and lungs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

oxygen

definition

A

Gaseous element making up about 20% of the air, which is needed by living organisms for respiration.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

palliative care

definition

A

Health care that focuses on relieving and preventing suffering, typically near the end of a patient’s life when they are terminally ill.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

qualitative

definition

A

Results that are not expressed as numbers or numerical data, eg they can be expressed as present or absent, or as colours.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

quantitative

definition

A

Results that can be expressed using numerical values.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

radioactive

definition

A

When unstable atoms give off particles that can be harmful to humans.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

radiotherapy

definition

A

Using ionising radiation to treat cancer by targeting cancerous cells.

51
Q

regenerate

definition

A

To restore something to its original form. For example, a catalyst is regenerated at the end of a reaction. Certain tissues and organs can regenerate themselves by producing new cells.

52
Q

What is a representative sample?

A

A representative sample is one that accurately represents the whole of the group.

53
Q

reproductive system

definition

A

The organs and tissues involved in producing offspring.

54
Q

respiration

definition

A

The chemical change that takes place inside living cells, which uses glucose and oxygen to release the energy that organisms need to live. Carbon dioxide is a by-product of respiration.

55
Q

risk factor

definition

A

Something that increases a person’s chances of developing a disease.

56
Q

stent

definition

A

A device, consisting of a wire mesh tube, used to keep a narrowed or blocked coronary artery open.

57
Q

stroke

definition

A

Damage to the brain caused by bleeding or blood clots in the brain’s blood vessels.

58
Q

tumour

definition

A

The lump of cells formed as a result of uncontrolled cell division.

59
Q

virus

definition

A

An ultramicroscopic infectious non-cellular organism that can replicate inside the cells of living hosts, with negative consequences.

60
Q

Diseases can be grouped into two types:

A
  • non-communicable

- Communicable

61
Q

What are non-communicable diseases?

A

Diseases which are not transferred between people or other organisms

62
Q

What are communicable diseases?

A

Diseases which can be transferred from one person to another, or from one organism to another, eg in humans, these include measles, food poisoning and malaria.

63
Q

Examples of non-communicable diseases

A
  • cancer
  • diabetes
  • genetic disorders and conditions
  • heart disease
  • neurological disorders
64
Q

Interactions between different types of diseases

overview

A

Different types of disease may interact. This can mean that the presence of one disease can lead to a higher chance of developing another disease.

65
Q

Interactions between different types of diseases

Defects in the immune system

A

Defects in the immune system mean that an individual is more likely to suffer from infectious diseases. For instance, human immunodeficiency virus (HIV) infections, which lead to AIDS, affect the immune system and lead to an increase risk of developing other infectious diseases.

66
Q

Interactions between different types of diseases

Viruses

A

Viruses living in cells can be the trigger for cancers. For instance, the majority of cases of cancer of the cervix are linked with a virus present in the female reproductive system.

67
Q

Interactions between different types of diseases

Reaction of the immune system to pathogens

A

The reaction of the immune system to pathogens and other foreign bodies can trigger allergic reactions that lead to skin rashes and asthma. For instance, severe respiratory infections in babies can lead to asthma in later childhood.

68
Q

Interactions between different types of diseases

severe physical illness

A

Severe physical ill health can lead to depression and other types of mental illness.

69
Q

Risk factors

A

Anything that increases a chance of developing a disease is called a risk factor. Risk factors can be caused by lifestyle factors or substances in a person’s body or their environment. Some diseases are caused by an interaction between risk factors.

Some risk factors have been proven to cause a disease. We know that smoking causes lung cancer. Other risk factors are linked but not proven.

70
Q

List a risk factor and effect of Type 2 diabetes

A

Risk factor: Obesity

Effect: Blood sugar levels cannot be regulated properly

71
Q

List a risk factor and effect of Liver cirrhosis

A

Risk factor: Alcohol

Effect: Scar tissue is formed in the liver which stops it removing toxins

72
Q

List a risk factor and effect of Lung cancer

A

Risk factor: Smoking

Effect: Smoking causes lung cancer and also the underdevelopment of unborn babies

73
Q

Causal mechanisms
Correlation
cancer

A

Research has established links between cancer and various lifestyle factors, chemicals produced in the body, or that enter the human body, and chemicals in the environment. Scientists have established several causal mechanisms for these risk factors.

74
Q

Correlation and cause

A

If there is a correlation between a particular factor and an outcome, it does not mean that the factor necessarily causes the outcome. Scientists must look for a possible mechanism by which the factor could be the likely cause.

75
Q

Correlation and cause

lung cancer

A

In the case of lung cancer, analyses of cigarette smoke have shown that at least 70 of the chemicals present in smoke will cause cancer in laboratory animals which establishes a causal link.

76
Q

Cancers

A

Cancers are non-communicable diseases. This means they cannot be caught. Instead they develop. Cancers occur when cell division goes wrong. This causes cells to grow out of control, which form a tumour.

77
Q

How are cancers looked for?

A

Cancers are looked for by doctors in a process called screening. This can be in an x-ray, in blood or urine tests or by using monoclonal antibodies.

78
Q

Causes of cancer

A

Many cancers are caused by smoking or drinking too much. Others are caused by infections such as the HPV virus. Other causes include the Sun’s UV rays and some environmental pollutants. The risk of cancer also increases as we get older.

79
Q

Treatment for cancers include:

A
  • chemotherapy
    using chemicals to kill cancerous cells
  • radiotherapy
    using x-rays to kill cancerous cells
  • palliative
    this helps a person who has fatal cancer to die as comfortably as possible
80
Q

Smoking increases the risk of cardiovascular disease in several ways:

A
  • Smoking damages the lining of the arteries, including the coronary arteries. The damage encourages the build-up of fatty material in the arteries. This can lead to a heart attack or a stroke.
  • Inhalation of carbon monoxide in cigarette smoke reduces the amount of oxygen that can be carried by the blood.
  • The nicotine in cigarette smoke increases heart rate, putting strain on the heart.
  • Chemicals in cigarette smoke increase the likelihood of the blood clotting, resulting in a heart attack or stroke.
81
Q

A person may develop COPD - chronic obstructive pulmonary disease. This condition includes the diseases chronic bronchitis and emphysema. In COPD:

A
  • smoking damages the bronchioles and can eventually destroy many of the alveoli in the lungs
  • the airways become inflamed and mucus, which normally traps particles in the lungs, builds up
  • the patient becomes breathless, and finds it more and more difficult to obtain the oxygen required for respiration
82
Q

Negative effects of CPOD

A

The damage caused by COPD is permanent. The disease cannot be cured, and can result in death. It is essential that the person seeks medical help to try to prevent progression of the disease.

83
Q

Lung cancer

A

The carcinogens in cigarette smoke also cause lung cancer. Almost all cases of lung cancer are caused by smoking - smaller numbers of cases are linked with air pollution and ionising radiation from radon gas, a radioactiveelement found in the environment in some parts of the country.

84
Q

The liver can regenerate its cells, but long-term alcohol abuse causes serious damage. Give the sequence it occurs in.

A

1) The patient begins by feeling sick, experiences weight loss and loss of appetite. There is a yellowing of the eyes, confusion, drowsiness and vomiting blood.
2) Alcohol causes lipids to build up in the liver which is called fatty liver disease.
3) Alcohol damage leads to alcoholic hepatitis, which can lead to death.
4) Cirrhosis of the liver can develop - the liver becomes scarred and loses its ability to function.
5) The changes are now irreversible and the reduced ability to process alcohol can also lead to brain damage.

85
Q

Alcohol affects the brain in several ways, it:

A
  • slows reaction time
  • causes difficulty walking
  • can impair memory
  • causes slurred speech
  • causes changes in sleep patterns and mood, including increased anxiety and depression.
86
Q

Longer term drinking of excess alcohol:

A
  • causes brain shrinkage
  • leads to memory problems
  • leads to psychiatric problems
  • may result in the patient requiring long-term care.
87
Q

Alcoholism has impacts on social and economic aspects:

A
  • there is increased violence, antisocial behaviour and other crime associated with alcoholism
  • there is an increased risk of accidents
  • there is increased absence from work
  • alcoholism increases the likelihood of relationship break-up
  • alcoholism causes mental decline
  • alcoholism increases treatment costs to NHS
88
Q

Obesity and cardiovascular disease

A

Obesity leads to high blood pressure and the build-up of fatty deposits in the arteries, which lead to cardiovascular disease. It also increases the likelihood of developing diabetes, another risk factor cardiovascular disease.

Being obese - with deposits of lipids in the abdomen - increases blood pressure beyond normal levels and increases levels of blood lipids.

89
Q

Obesity and type 2 diabetes

A

Body fat also affects the body’s ability to use insulin.

Type 2 diabetes is where the body’s cells lose their sensitivity to insulin – they no longer respond, or respond less effectively, to the insulin that’s produced.

Obesity accounts for 80 to 85 per cent of the risk of type 2 diabetes. Rising obesity is linked with ‘western diet’ - a diet that includes energy-rich ‘fast foods’ and an inactive lifestyle.

90
Q

How to reduce the risk of developing cardiovascular disease.

A

The risk of developing cardiovascular disease and type 2 diabetes can be reduced by eating a balanced diet, with unrefined, unprocessed, ‘whole foods’, and taking regular exercise.

91
Q

BMI calculation

A

weight (kg) / (height (m))^2

92
Q

Samples must be representative - they must reflect the population under study. They cannot:

A
  • focus on certain groups and ignore others

- be affected by bias

93
Q

To obtain a representative sample:

A
  • the study must be wide, and cover all groups in the population being studied
  • the study must be random within these groups
94
Q

When working with samples of human populations, studies must take account of possible variations owing to differences:

A
  • between the sexes
  • resulting from people of different ages taking part
  • in people’s lifestyles, which could affect the study
95
Q

principles of sampling

what is a subsection and what is it used?

A

Analyses can be carried out on sub-sets of data within the whole study, so that comparisons can be made within the same age group, for instance.

96
Q

Principles of sampling

In scientific models

A

In scientific studies, it may be difficult to control lifestyle factors that have the potential to affect the study, particularly if the study is long-term. People involved in a long-term study of the effects of alcohol intake, for instance, will have different lifestyle factors, for instance diet and exercise that could potentially affect the results of the study.

97
Q

Bar charts

A

Bar charts show data collected for separate groups. The height of the bar is proportional to the measured number or frequency.

Note that the bars in a bar chart are all the same width. They do not touch each other as they show distinct categories.

98
Q

Histograms

A

Histograms look similar to bar charts, but show how the frequently data occur within certain ranges.

The independent variable is therefore continuous and is divided into sub-sections or classes.

The bars of a histogram are next to each other. The area of each bar is proportional to the frequency of each class interval. The bars of a histogram may not be the same width - it depends on the range they cover.

99
Q

Line graphs

A

Line graphs display data where both variables are continuous.

With line graphs, you have a choice between connecting the plots point-to-point, or using a line of best fit.

Joining dots point to point is essential to show fluctuations in data - for instance, with the death rates - above - or a person’s body temperature. We can also connect data point to point when we are confident of their quality.

100
Q

Line of best fit

A

A line of best fit looks at how variables behave in relation to each other - it is used to establish or display a correlation or a trend. These relationships may not be obvious from a table of data or could be obscured by experimental errors. Lines of best fit are also used to make predictions.

101
Q

Coronary heart disease

A

Coronary heart disease occurs when a waxy plaque builds up inside the coronary arteries that supply the heart with oxygen. Drugs and surgery can help to control cardiovascular disease.

102
Q

Ways of treating cardiovascular disease
Medication

How do statins work?

A

Statins are drugs that help to lower cholesterol in the blood. They do this by lowering the production of cholesterol in the liver.

103
Q

Ways of treating cardiovascular disease
Medication

When are statins prescribed?

A

Statins are prescribed for people with heart disease or who have a high risk of developing it. They need to be taken long-term. Cholesterol levels will rise again if a person stops taking them.

104
Q

Ways of treating cardiovascular disease
Medication

Who are statins not suitable for?

A

Statins are not suitable for everyone - they should not be prescribed for people with liver disease, or pregnant or breast feeding women.

105
Q

Ways of treating cardiovascular disease
Medication

Side effects of statins

A

Some patients taking statins often experience side-effects such as headaches and memory loss. There have been reports of statins being linked with type 2 diabetes and liver damage.

106
Q

Ways of treating cardiovascular disease
Surgical procedures

stents

A

Coronary arteries that are blocked or have become narrow can be stretched open and a stent inserted to restore and maintain blood flow.

They can be used in instances where drugs are less effective, and offer a longer term solution. Stents are made from metal alloys and do not lead to an immune response in the patient.

107
Q

Ways of treating cardiovascular disease
Surgical procedures
stents

Around 75,000 operations are carried out each year. Risk factors depend on the patient’s:

A
  • age
  • general health
  • whether they have had a heart attack

The operation is safe as it does not involve surgery, but there is a risk of bleeding, heart attack or stroke.

108
Q

Ways of treating cardiovascular disease
Surgical procedures
Heart transplants

When is a heart transplant required?

A

A heart transplant is required in cases of heart failure. Coronary heart disease can lead to heart failure. The heart fails to pump sufficient blood and organs are starved of oxygen. There will be degrees of severity of heart failure.

109
Q

Ways of treating cardiovascular disease
Surgical procedures

Heart transplants

A

A donor heart is transplanted. In rare cases, a heart is transplanted along with lungs.

A consultant assesses the patient’s condition. If other treatments are not managing the heart condition, a transplant may be recommended and a patient will be put on a waiting list. A transplant puts major strain on the body, and the benefits and risks will be evaluated including whether the patient’s condition is sufficiently severe and other health factors.

110
Q

Ways of treating cardiovascular disease
Surgical procedures
Heart transplants

artificial hearts

A

Artificial hearts are plastic devices used occasionally to keep patients alive whilst waiting for a heart transplant. They can also be used to allow a patient’s heart to rest to help it recover.

111
Q

Ways of treating cardiovascular disease
Surgical procedures
Heart transplants

After the transplant, the patient will:

A
  • need time to heal, recover and build up strength
  • have to take drugs called immunosuppressant drugs for the rest of their life - this prevents the person’s immune system from rejecting the donor heart
  • have an increased risk of infection because of these drugs
112
Q

Drugs used alongside heart conditions and transplants prolong life.
Evaluation of different treatment methods

List the advantages of the treatment: statins (drugs)

A
  • Reduce the risk of heart attack.
  • Studies have shown a decrease in ‘bad cholesterol’ and an increase in ‘good cholesterol’.
  • Used to reduce high cholesterol levels that have genetic causes.
  • May have beneficial effects on other conditions.
113
Q

Drugs used alongside heart conditions and transplants prolong life.
Evaluation of different treatment methods

List the disadvantages of the treatment: Statins (drugs)

A
  • Not suitable for people with liver disease.
  • Some side effects.
  • Must be taken for life.
  • Should not be taken if pregnant or breastfeeding.
114
Q

Drugs used alongside heart conditions and transplants prolong life.
Evaluation of different treatment methods

List the advantages of the treatment: Heart transplant

A

improve quality of life

115
Q

Drugs used alongside heart conditions and transplants prolong life.
Evaluation of different treatment methods

List the disadvantages of the treatment: Heart transplant

A
  • Few donor hearts are available.
  • Recovery time is long.
  • There is a risk of rejection by the body’s immune system.
116
Q

Drugs used alongside heart conditions and transplants prolong life.
Evaluation of different treatment methods

List the advantages of the treatment: Stents

A

Widen coronary arteries that have not responded to drug treatment. The recovery time is short following insertion of the stent.

117
Q

Drugs used alongside heart conditions and transplants prolong life.
Evaluation of different treatment methods

List the advantages of the treatment: Stents

A
  • Widen coronary arteries that have not responded to drug treatment.
  • The recovery time is short following insertion of the stent.
118
Q

Drugs used alongside heart conditions and transplants prolong life.
Evaluation of different treatment methods

List the advantages of the treatment: lifestyle changes

A

These include stopping smoking, reducing alcohol intake, eating a balanced diet and regular exercise. These changes will improve the health of all people; those with and without cardiovascular disease.

119
Q

Drugs used alongside heart conditions and transplants prolong life.
Evaluation of different treatment methods

List the advantages of the treatment: lifestyle changes

A

These include stopping smoking, reducing alcohol intake, eating a balanced diet and regular exercise.

These changes will improve the health of all people; those with and without cardiovascular disease.

120
Q

Drugs used alongside heart conditions and transplants prolong life.
Evaluation of different treatment methods

List the disadvantages of the treatment: Lifestyle changes

A

These include stopping smoking, reducing alcohol intake, eating a balanced diet and regular exercise.

These changes will improve the health of all people; those with and without cardiovascular disease.

121
Q

What is the carcinogen in cigarettes?

A

Tar

122
Q

Which organ in the body can regenerate?

A

Liver

123
Q

What type of drug is alcohol?

A

Depressant

124
Q

If, in an investigation of a disease, two sets of data show a correlation, what must a scientist do to establish that it was a change in one variable that led to a change in the other?

A

To establish that one variable causes a change in another, a possible causal mechanism must be looked for.