Section 5

Question 1

Communicable and noncommunicable diseases

Answer 1

Communicable – can be spread between individuals - caused by pathogens(viruses, bacteria, fungi, protists)
Noncommunicable – disease can’t be transmitted between individuals

Question 2

Health and disease

Answer 2

World health organisation define health as a state of complete physical mental and social well-being
If you’re affected by some diseases it makes you more susceptible to others – body becomes weak and so can’t fight it off

Question 3

STI’S - chlamydia

Answer 3

Sexually transmitted bacterial infection – can only reproduce the living cells

Question 4

STI’S - hiv

Answer 4

Sexually transmitted virus – it affects and kills white blood cells – leads to aids – immune system deteriorates and fails – vulnerable to infection by other pathogens – Spread via infected bodily fluids

Question 5

Physical barriers to infection

Answer 5

Skin – contains keratin which makes surface tough
Hair – produces an antiseptic sebum that kills microorganisms and waterproofs skin
Cilia – learning of breathing system, traps bacteria

Question 6

Chemical barrier of infection

Answer 6

Stomach acid – makes hydrochloric acid, kills bacteria

Lysozyme – in eyes, kills bacteria

Question 7

Fighting diseases

Answer 7

B lymphocytes – every pathogen has unique molecules on the surface called antigens when the leucocytes come across antigen on pathogen produces antibodies which sticks on and destroys

Three lines of defence – chemical and physical barriers, Immune system, antibiotics

Question 8

Immunisation

Answer 8

Immunisation Stops you getting infections – inject dead or inactive pathogens and body makes antibodies to destroy them – trigger memory lymphocytes to be made
Memory lymphocytes give immunity to later infection

Question 9

Memory lymphocytes

Answer 9

When a pathogen enters the body for first-time response is slow as aren’t many B lymphocytes this can make the antibodies need to lock onto the antigenMemory lymphocytes also produced in response to foreign antigen is he is raining blood in case of secondary attack second immune responses faster and stronger

Question 10

Antibiotics and other medicines

Answer 10

1. tested on cells – to see if it can enter and side-effects
2. animal testing – minimise risk to humans
3. Small clinical trials – test on healthy, check safety on humans and side-effects
4. large clinical trials – people with disease, workout correct dose and side-effects

Question 11

Antibiotics advantages and disadvantages

Answer 11

ADV- safe, side-effects decreased
DIS – expensive, takes time, disease may spread rapidly
Used to treat bacterial infections

Question 12

Noncommunicable diseases

Answer 12

Lifestyle factors may increase risk
Smoking – cardiovascular disease, nicotine increases heart rate which increases blood pressure and high blood pressure damages artery walls, buildup of fatty deposit = heart attack
Alcohol and lack of exercise are risk factors associated with CD

Question 13

Measures of obesity

Answer 13

BMI= weight ÷ height^2
Not always reliable, muscle weighs a lot
Waist: hip ratio (waist ÷ hip)

Question 14

Treatments for cardiovascular disease

Answer 14

Warfarin– makes blood clots less likely to form
Antihypertensives reduce blood pressure
Started reduces amount of cholesterol in bloodstream
Treatment – diet, exercise, stop smoking
Cholesterol blocked arteries restricts blood flow triggering blood clots, heart muscle deprived of oxygen