Topic 5 - Health, disease and the development of medicines

Question 1

What is health?

Answer 1

Health is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity

Question 2

What is a disease?

Answer 2

A disease is a condition where part of an organism doesn’t function properly. There are two sorts of disease - communicable and non-communicable

Question 3

What are communicable diseases?

Answer 3

Diseases that can be spread between individuals.

Question 4

What are non-communicable diseases?

Answer 4

Non-communicable diseases can’t be transmitted between individuals. They include things like cancer and heart disease

Question 5

Explain why the presence of one disease can lead to a higher susceptibility to other diseases?

Answer 5

If you’re affected by one disease, it could make you more susceptible to other as your body may become weakened by the disease, so its less able to fight off others

Question 6

What is a pathogen?

Answer 6

A pathogen is a disease-causing organism. Pathogens are organisms such as viruses, bacteria, fungi and protists that cause communicable diseases.

Question 7

How does cholera develop?

Answer 7

Cholera is a communicable disease which develops from a pathogen - a bacterium called Vibrio cholerae.
Symptoms - Diarrhoea
It spreads via contaminated water sources.
In order to prevent transmission, people must have access to clean water supplies.

Question 8

How does tuberculosis develop?

Answer 8

Tuberculosis is a communicable disease which develops from a pathogen - a bacterium called Mycobacterium tuberculosis.
Symptoms- Coughing and lung damage
It spreads through the air when infected individuals cough
In order to prevent transmission, infected people should avoid crowded public spaces, practise good hygiene and sleep alone. Their homes should be well ventilated.

Question 9

How does malaria develop?

Answer 9

Malaria is a communicable disease which develops from a pathogen - a protist.
Symptoms - Damage to red blood cells and sometimes to the liver
It spreads from Mosquitos which act as animal vectors, they pass on the protist to humans
In order to prevent transmission, Mosquito nets and insect repellent should be used to stop the mosquitos

Question 10

How does chalara ash dieback develop?

Answer 10

Chalara ash dieback is a communicable disease which develops from a pathogen - a fungus that infects ash trees
Symtoms - leaf loss and bark lesions
It spreads from being carried through the air by the wind and when diseased ash trees are moved
In order to prevent transmission, remove young, infected ash trees and replant with different species. Restrict the import or movement of ash trees

Question 11

What is an STI?

Answer 11

A sexually transmitted infection is an infection that spreads through sexual contact, including sexual intercourse

Question 12

What is HIV?

Answer 12

HIV is the human immunodeficiency virus. It infects and kills white blood cells, which are really important in the immune response. HIV eventually leads to AIDS

Question 13

What is AIDS?

Answer 13

AIDS are an acquired immune deficiency syndrome. This is when the infected person’s immune system deteriorates and eventually fails - because of this, the person becomes very vulnerable to opportunistic infections by other pathogens

Question 14

What are viruses?

Answer 14

Viruses are a protein coat around a strand of genetic material. They have to infect living cells in order to reproduce. Specific types of viruses will only infect specific cells

Question 15

Explain how HIV is spread via infected bodily fluids?

Answer 15

These bodily fluids include blood, semen and vaginal fluids. This means that one of the main ways to prevent the spreading of HIV is to use protection. Medication can reduce the risk of an infected individual passing the virus on to others during sex so screening and proper treatment are also important

Question 16

What is chlamydia?

Answer 16

A sexually transmitted bacterial infection. Chlamydia is a kind of bacterium, but it behaves in a similar way to a virus because it can only reproduce inside host cells. It can result in infertility in men and women

Question 17

What are the ways to reduce the spreading of chlamydia?

Answer 17

• wearing a condom when having sex
• screening individuals so they can be treated for the infection
• avoiding sexual contact

Question 18

What do physical and chemical barriers do?

Answer 18

Stop pathogens entering the body

Question 19

What are examples of physical barriers?

Answer 19

Mucus, Cilia and skin

Question 20

What are examples of chemical barriers?

Answer 20

Lysozymes and hydrochloric acid

Question 21

How does the skin act as a physical barrier?

Answer 21

The skin acts as a barrier to pathogens and if it gets damaged blood clots quickly seal cuts and keep microorganisms out

Question 22

How do hair and mucus act as a physical barrier?

Answer 22

Hairs and mucus in your nose trap particles that could contain pathogens

Question 23

How does mucus and cilia act as physical barriers?

Answer 23

Cells in your trachea and bronchi also produce mucus, which traps pathogens. Other cells that line the trachea and bronchi have cilia. These are hair-like structures which waft the mucus up to the back of the throat where it can be swallowed

Question 24

How does hydrochloric acid act as a chemical barrier?

Answer 24

The stomach produces hydrochloric acid. This kills most pathogens that are swallowed

Question 25

How does lysozyme act as a chemical barrier?

Answer 25

The eyes produce a chemical called lysozyme (in tears) which kills bacteria on the surface of the eye

Question 26

What is the role of the immune system?

Answer 26

To attack pathogens. If pathogens make it into your body, your immune system destroys them

Question 27

What is the role of white blood cells in your immune system?

Answer 27

They travel around in your blood and crawl into every part of you, looking for pathogens

Question 28

What are B-lymphocytes?

Answer 28

A type of white blood cell that are involved in the specific immune response - this is the immune response to a specific pathogen.

Question 29

How does the immune system work?

Answer 29

• Every pathogen has unique molecule on its surface called antigens.
• When your B-lymphocytes come across an antigen on a pathogen they start to produce proteins called antibodies. Antibodies bind to the new invading pathogen so it can be found and destroyed by other white blood cells. The antibodies produced are specific to that pathogen.
• The antibodies are then produced rapidly and flow all round the body to find similar pathogens

Question 30

What is an antibody?

Answer 30

A blood protein produced in response to and counteracting a specific antigen.

Question 31

What is an antigen?

Answer 31

A toxin or other foreign substance which induces and immune response in the body, especially the response of antibodies

Question 32

What is the role of memory lymphocytes in the secondary response to the antigen?

Answer 32

As well as antibodies, memory lymphocytes are produced in response to a foreign antigen, they remain in the body for a long time. This now means that a humans immune system has the ability to respond quickly to a second infection. The secondary immune response is faster and stronger and gets rid of the pathogen.

Question 33

How do immunisations stop you getting infections?

Answer 33

Immunisation involves injecting dead/inactive pathogens into the body. These are antigenic so even though they’re harmless, your body makes antibodies to destroy them. They also trigger memory lymphocytes to be made. If live pathogens of the same type get into the body, there will already be memory lymphocytes that can cause a fast secondary immune response. = less likely to get disease

Question 34

What are antibiotics used for?

Answer 34

Antibiotics can only be used to treat bacterial infections because they inhabit cell processes in the bacterium but not the host organism

Question 35

What is involved in the process of developing new medicine?

Answer 35

The process of developing new medicines has many stages, including discovery, development, preclinical and clinical testing

Question 36

What is preclinical testing?

Answer 36

The testing of a drug, procedure or other medical treatment in animals before trials may be carried out in humans. Drugs are tested on animals, to see if it works and to found out how toxic it is and to find the best dosage

Question 37

What is clinical testing?

Answer 37

Research investigations in which people volunteer to test new treatments as a mean to prevent, detect, treat or manage various diseases/conditions. Firstly tested on healthy people to see if there are any side effects.

Question 38

How are non-communicable diseases caused?

Answer 38

By the interaction of a number of factors including cardiovascular diseases, many forms of cancer, some lung and liver diseases and diseases influenced by nutrition

Question 39

What are risk factors?

Answer 39

Things that are linked to an increase in the likelihood that a person will develop a certain disease during their lifetime.

Question 40

How does smoking effect health?

Answer 40

Smoking is a risk factor associated with cardiovascular diseases. This is because:

• Nicotine increases heart rate, which increases blood pressure
• High blood pressure damages artery walls, which contribute to the build up of fatty deposits in the arteries. These deposits restrict blood flow and increase the risk of a heart attack or stroke.
• Smoking increases the risk of blood clots forming in arteries, which can restrict or block blood flow, leading to heart attack/stoke

Question 41

How does alcohol affect health?

Answer 41

Drinking too much alcohol is a major risk factor for the development of liver disease. This is because alcohol is broken down by enzymes in the liver and some of the products are toxic. Drinking too much over a long period of time can cause permanent liver damage

Question 42

How does diet affect health?

Answer 42

A diet with too many or too few nutrients can lead to malnutrition and non-communicable diseases

Question 43

What are the risk factors for non-communicable diseases?

Answer 43

Smoking, alcohol, lack of exercise, diet, cancer, liver/lung diseases, obesity

Question 44

What are effects of non-communicable diseases?

Answer 44

• Areas with high level of obesity/smoking/alcohol consumption, theres likely to be a high occurrence of non-communicable diseases. This can put pressure on nearby hospitals
• Costly at a national level, can affect country’s economy as people are unable to work
• Cause of death, can hold back the development of a country(less food and water)

Question 45

What is your BMI?

Answer 45

Body mass index shows whether your underweight, normal, overweight or obese
BMI = weight(kg)➗height(m)^2

Question 46

What is the waist to hip ratio?

Answer 46

Waist to hip = waist circumference➗hip circumference

a ratio above 1.0 for males and 0.85 for women indicates you’re carrying too much weight around your abdomens

Question 47

How is life long medication used to treat cardiovascular diseases?

Answer 47

Medication can reduce the amount of cholesterol in the bloodstream, slowing down the rate which fatty acids form. They also make blood clots less likely to form and reduce blood pressure which helps prevent damage to blood vessels.

Question 48

How do surgical procedures treat cardiovascular diseases?

Answer 48

Tubes are inserted into arteries, keeping them open, making sure blood passes through to the heart muscles - lowering the risk of a heart attack.
A piece of healthy vessel can be taken and used to bypass a blocked section of blood vessels.
Heart can be replaced with a donor heart

Question 49

How do lifestyle changes treat cardiovascular diseases?

Answer 49

People are encouraged to eat a healthy, balanced diet which is low in saturated fat. They may also exercise regularly and if necessary may need to stop smoking. These allow a person to lose weight and lower their blood cholesterol