Disease Flashcards
(114 cards)
1
Q
What is a communicable disease?
A
Disease that can be passed from one organism to another.
2
Q
What pathogens cause communicable diseases?
A
Bacteria, viruses and fungi
3
Q
What are pathogens?
A
Disease-causing microbes.
4
Q
What are some examples of communicable diseases?
A
HIV (which leads to AIDS)
Colds and flu
Human papilloma virus (HPV)
Salmonella food poisoning
Tuberculosis
Chlamydia
Athlete’s foot
Potato blight
5
Q
What type of pathogen causes HIV?
A
Virus
6
Q
How is HIV spread?
A
Exchange of bodily fluids during sex.
Infected blood.
7
Q
How is HIV controlled, prevented and treated?
A
Using condom reduces risk of infection.
Drug addicts not sharing needles.
Currently controlled by drugs.
8
Q
What type of pathogen causes colds and flu?
A
Virus
9
Q
How are colds and flu spread?
A
Airborne droplet infection.
10
Q
How are colds and flu controlled, prevented and treated?
A
Flu vaccination for targeted groups.
11
Q
What type of pathogen causes human papilloma virus (HPV)?
A
Virus
12
Q
How is HPV spread?
A
Sexual contact.
13
Q
How is HPV controlled, prevented and treated?
A
HPV vaccination given to 12 to 13 year old girls to protect against developing cervical cancer.
14
Q
What type of pathogen causes salmonella food poisoning?
A
Bacterium
15
Q
How is salmonella spread?
A
From contaminated food.
16
Q
How is salmonella controlled, prevented and treated?
A
Always cooking food thoroughly.
Not mixing cooked and uncooked foods can control spread.
Treatment with antibiotics.
17
Q
What type of pathogen causes tuberculosis?
A
Bacterium
18
Q
How is tuberculosis spread?
A
Airborne droplet infection.
19
Q
How is tuberculosis controlled, prevented and treated?
A
BCG vaccination.
If contracted, treated with drugs, including antibiotics.
20
Q
What type of pathogen causes chlamydia?
A
Bacterium
21
Q
How is chlamydia spread?
A
Sexual contact.
22
Q
How is chlamydia controlled, prevented and treated?
A
Using condom will reduce risk of infection.
Treatment with antibiotics.
23
Q
What type of pathogen causes athlete’s foot?
A
Fungus
24
Q
How is athlete’s foot spread?
A
Contact
25
How is athlete’s foot controlled, prevented and treated?
Reduce infection risk by avoiding direct contact in areas where spores likely to be present, e.g. wear flip flops in changing rooms / swimming pools.
26
What type of pathogen causes potato blight?
Fungus
27
How is potato blight spread?
Spores spread in air from plant to plant, particularly in humid and warm conditions.
28
How is potato blight controlled, prevented and treated?
Crop rotation and spraying plants with fungicide.
29
What is the cost to the NHS on treating communicable disease?
Cost of medication (treatment / drugs).
Cost of salaries (doctors / nurses / other staff).
Upkeep of hospitals.
30
What is the cost to society of communicable diseases?
Missed days from work / school.
Mental health issues.
Family stress.
31
What are the first lines of defence against communicable disease in the body?
Skin
Tears and salvia
Hydrochloric acid in stomach
Ciliated epithelial cells
Eyes / eye lids
32
How does the skin defend against communicable diseases?
Physical barrier (scab formation).
33
How does tears and salvia defend against communicable diseases?
Lysosomal enzymes that hydrolyse bacteria.
34
How does the hydrochloric acid in the stomach defend against communicable diseases?
Low pH denatures enzymes and destroys pathogens.
35
How do ciliated epithelial cells defend against communicable diseases?
Mucus trap dust / dirt / pathogens.
Ciliate waft to back of throat to be coughed out.
36
How do the eyes / eye lids defend against communicable diseases?
Blink reflex - physical barrier.
37
What are the 3 types of white blood cells that carry of secondary immune response?
Lymphocytes
Phagocytes
Memory cells
38
What is a lymphocyte?
A type of white blood cell that produces antibodies.
39
What is an antigen?
A distinctive marker on a microorganism that leads to the body producing specific antibodies.
40
What is an antibody?
Structure produced by lymphocytes that has a complementary shape (can attach to) antigens on a particular microorganism.
41
What is a memory lymphocyte?
Special type of lymphocyte that can remain in the body for many years and produce antibodies quickly when required.
42
How do the lymphocytes help to destroy microorganisms that have entered the body?
1. Antigens on microorganisms cause lymphocytes to produce antibodies.
2. Antibodies complementary in shape to antigens.
3. Antibodies latch onto antigens, linking them together.
4. Immobilises (clumps) microorganisms and then can be destroyed.
43
How do the phagocytes help to destroy microorganisms that have entered the body?
Carry out phagocytosis by engulfing and digesting the clumped microorganisms.
44
What does clumping the harmful microorganisms do?
Prevents them from moving around body, and flags them up for phagocytes to engulf and digest them.
45
What does immunity mean?
Antibody levels are high enough (or high enough levels can be produced quickly enough) to combat microorganism infections.
46
What are the types of artificial immunity?
Active
Passive
47
Where does passive immunity come from?
Antibodies from source directly injected in body, e.g. tetanus.
48
Where does active immunity come from?
Vaccination of dead / attenuated does of pathogen, e.g. MMR vaccination.
49
What are the characteristics of passive immunity?
Fast acting.
Only lasts a short period of time.
50
What are the characteristics of active immunity?
Slow acting.
Provides long-lasting protection.
51
What are some examples of passive immunity?
Breastfeeding passing antibodies to baby.
Anti-venom for snake-bites.
52
What are some examples of active immunity?
Body producing antibodies to combat an infection.
Vaccines.
53
What does immunity involve?
Memory cells in secondary immune response.
54
What are the 2 types of natural immunity?
Innate
Acquired
55
Where does innate immunity come from?
Colostrual route - from mother to baby via breast milk.
Placenta route - from mother to foetus via placenta.
56
Where does acquired immunity come from?
Develops during life as result of infection / contact with pathogen and recovering, e.g. chicken pox.
57
What are the characteristics of innate immunity?
Antibodies are already made.
Fast acting.
Short lived immunity.
58
What are the characteristics of acquired immunity?
Antibodies actively produced.
Slow acting.
Longer lived immunity.
59
What is a vaccination?
Injection of dead or modified pathogens with purpose of raising antibody and memory lymphocyte levels in blood.
60
How do vaccinations work?
Antigens on dead or modified pathogens cause body to produce antibodies.
Raises antibody levels in blood; if body becomes infected with same pathogens again later, memory lymphocytes already present in body to rapidly produce antibodies to prevent disease developing.
61
What are the 2 types of plant defense mechanisms against microorganisms?
Structural
Chemical
62
What are the plant structural defence mechanisms against microorganisms?
Waxy cuticles
Thick cell walls
63
How do the plant structural defence mechanisms defend against microorganisms?
Prevent entry of microorganisms.
64
What are the plant chemical defence mechanisms against microorganisms?
Antimicrobial chemicals defend against bacteria, viruses or fungi.
65
What are some examples of plant chemical defence mechanism against microorganisms?
Chemicals in mint kills bacteria.
Digitalis in foxgloves kills insects / slugs.
66
When and who discovered penicillin?
1928, Alexander Flemming
67
How was penicillin discovered (mark scheme answer)?
1. Bacteria grown on agar plates.
2. Plates contaminated.
3. Penicillium is a fungus.
4. Produces a chemical / substance / antibiotic.
5. Chemical diffuses.
6. Bacteria killed.
7. Reference to clear area.
68
Who were able to isolate the penicillin and grow it in bio digesters?
Florey and Chain.
69
What is an antibiotic?
Chemical produced by fungi that kills bacteria.
70
How can some bacteria develop antibiotic resistance?
Mutation (change in DNA).
71
What is a bacteria that is resistant to a number of antibiotics called.
A superbug.
72
What is an example of a superbug?
MRSA
73
What are the factors that can cause MRSA to be prevalent in hospitals?
Poor standards of hygiene.
Patients have weak immune systems.
Wounds allow molecules to enter the body.
Antibiotics-rich environment.
74
What are the measures that can help to eradicate superbugs in hospitals?
Increased levels of hygiene.
Immediate clean up of body fluid spills.
Wearing gloves.
Greater care in administrating antibiotics.
75
What is peer review?
Development of new medicines and other scientific research is properly reviewed by other scientists.
76
What are the 2 types of clinical trials?
Preclinical trials.
Clinical trials.
77
What are the 2 stages of preclinical trials?
Stage 1 - in vitro testing.
Stage 2 - animal testing.
78
What happens during stage 1 of preclinical trials?
Testing on living cells and tissues in laboratory.
79
Why are drugs tested on live cells and tissues during stage 1 of preclinical trials?
To see if they are effective and that drug does not harm living cells.
Allows testing before drug used on living organisms.
Initial ‘trial-and-error’ process.
80
What happens during stage 2 of preclinical trials?
Testing on animals to check how they work on whole organisms.
81
What are the benefits of testing drugs on animals during stage 2 of preclinical trials.
Avoids testing on humans at this stage.
Can check for side effects in living organisms.
82
What are the disadvantages of testing drugs on animals during stage 2 of preclinical trials.
Animals are different from humans, so drugs may react differently when used in humans.
Raises ethical issues.
83
What happens during clinical trials?
Testing on small numbers of healthy human volunteers and patients.
84
What is tested for during clinical trials?
How effective drug is at doing what it is meant to do.
Finding optimum dosage.
Side effects.
85
What must be avoided when working with bacteria and fungi in a laboratory?
Contamination of cultures used.
Growth of unwanted, pathogenic microorganisms.
86
What do aseptic techniques include?
No eating or drinking in lab.
Wiping bench with disinfectant / alcohol.
Not growing microorganisms at body temperature.
Using sterile loops when transferring cultures.
Flaming culture bottle necks to prevent contamination.
Sterilising (using autoclave) or disposing of all used equipment.
Washing hands thoroughly.
87
What is the method for using aseptic techniques when transferring microorganisms?
1. Pass metal loop through flame of Bunsen burner.
2. Allow metal to cool.
3. Remove lid of culture bottle and glide loop over surface of agar, called inoculation.
4. Replaced lid to prevent contamination, sweep neck of bottle through flame to destroy any airborne microorganisms.
5. Spread microbes over surface of agar in Petri dish by gently gliding metal loop over nutrient agar surface, called plating, make sure lid at angle to stop unwanted microbes entering.
6. Metal loop then heated again it high temperature to ensure any microorganisms on loop are destroyed.
7. Petri dish should be taped and incubated in oven at 25oC.
8. When carrying out transfer important to work up close to Bunsen burner as creates upward current of air carrying microbes in air away, avoiding contamination.
9. When investigation complete important to clean all work surfaces and hands and safely dispose of bacterial cultures.
88
What are non-communicable diseases?
Diseases not passed on from one person to another, e.g. non-infectious.
89
How are non-communicable diseases caused?
Inheriting a gene for the disease (genetics).
Lifestyle factors.
90
What lifestyle factors can cause non-communicable diseases?
Diet high in saturated fat.
Smoking.
Drinking alcohol.
Lack of exercise.
Overexposure to UV lights ( may cause skin cell mutation, leading to cancer).
91
What harmful substances are contained in cigarettes?
Tar.
Nicotine.
Carbon monoxide.
92
What are the harmful effects of tar in cigarettes on people?
Bronchitis (narrowing of bronchioles).
Emphysema (damage to alveoli, reducing surface area for gas exchange).
Lung cancer (caused by abnormal cell division).
93
What are the harmful effects of nicotine in cigarettes on people?
Addictive.
Irregular heart rate.
94
What are the harmful effects of carbon dioxide in cigarettes on people?
Has high affinity for haemoglobin, replacing oxygen in red blood cells reducing oxygen carry capacity of red blood cells.
95
How does cardiovascular disease / a heart attack occur?
1. Build up of cholesterol in coronary artery leads to blockage.
2. Reduces / narrows lumen of artery.
3. Hence reduction in blood flow to heart cells.
4. Less oxygen and glucose delivered to heart cells.
5. Less respiration in heart cells so less energy released and heart cells die.
6. Heart muscle has to work harder, resulting in heart attack and possible death.
96
What is angiography?
Procedure in which dye, usually containing iodine, added to blood vessel close to skin, via thin tube.
X-ray pictures used to detect blockages in coronary artery caused by build up of plague.
97
What is angioplasty?
Procedure in which catheter with inflated ballon is guided through aorta and into coronary artery to remove plaque build-up and widen lumen to increase blood flow.
98
How is a stent used to keep the lumen in the coronary artery wide?
1. Stent placed in location of plaque.
2. Balloon inflated with fluid, stent expands and pushes back plaque.
3. Balloon deflated and removed along with elastic tube.
4. Stent left to keep lumen wide and artery open to increase blood flow.
99
What drugs can be given to patients with cardiovascular disease to reduce the chances of a heart attack occurring?
Statins
Aspirin
100
How do statins reduce the chance of a heart attack occurring?
Reduce blood cholesterol.
101
How does aspirin reduce the chance of a heart attack occurring?
Makes blood thinner.
102
How are strokes caused?
Circulatory blockage in brain which leads to death of brain cells.
Size of area and location of blockage determines effect and severity of damage.
103
What is cancer?
A range of diseases caused by uncontrolled cell division.
104
What is a benign tumour?
Tumour that is encapsulated and does not spread to other parts of body.
105
What is a malignant tumour?
Tumour that is not surrounded by a capsule and is capable of spreading around body.
106
What are the causes of some cancers?
UV radiation
Chemicals in cigarette smoke
Viruses
107
How can UV radiation cause some cancers?
Can cause skin cancer.
108
How can people protect against UV radiation causing skin cancer?
Covering up.
Using high-factor sun screen.
Avoiding sun in hottest part of day.
109
How can chemicals in cigarette smoke cause some cancers?
Tar causes lung cancer.
110
How can people protect against chemicals in cigarette smoke causing skin cancer?
Not smoking.
111
How can viruses cause some cancers?
HPV virus linked to cervical cancer.
112
How can people protect against viruses causing skin cancer?
HPV vaccine.
113
What are the economic costs to the NHS of treating disease?
Many diseases involve long-term treatment, e.g. heart disease and cancer.
May involve long stays in hospital.
Expensive drugs and medicines may be required.
Highly trained and specialist staff are required.
114
What are the cost to families of diseases?
People who care for those who are ill may need time off work as well.
Individuals who are ill may not be as productive in workplace.
