F212 Health And Disease Flashcards
0
Q
Disease
Definition
A
A departure from good health caused by a malfunction of the mind or body
1
Q
Health
Definition
A
A state of mental, physical and social well being, not just the absence of disease
2
Q
Pathogen
Definition
A
An organism that a uses disease
3
Q
Parasite
Definition
A
An organism that lives on or inside a host organism causing harm to its host
4
Q
Transmission
Definition
A
The way in which a parasitic microorganism travels from one host to another
5
Q
Malaria
Cause
A
Eukaryotic organisms for the genus Plasmodium
6
Q
Malaria
Transmission
A
The vector for malaria is the female Anopheles mosquito
The mosquito bites an infected person and takes in the Plasmodium gametes from their blood
Plasmodium zygotes develop inside the mosquito’s stomach then move to the salivary glands
When the mosquito bites someone else it injects saliva as an anticoagulant transferring the Plasmodium
Inside the new host the Plasmodium moves to the liver where it produces gametes
The gametes move to the red blood cells
7
Q
Malaria
Global Distribution
A
South America
Sub-Saharan Africa
North Africa
South East Asia
8
Q
Malaria
Global Impact
A
Increases drug resistance by Plasmodium
40% of the world’s population love in malarial areas
Difficult to develop a vaccine as there are different species of Plasmodium that cause malaria
9
Q
Malaria
Control Measures
A
Mosquito nets to prevent them from biting at night
Drugs to fight the Plasmodium
Reduce Mosquito populations
Destroy mosquito larva
10
Q
HIV / AIDS
Cause
A
Human immunodeficiency virus
11
Q
HIV / AIDS
Transmission
A
Exchange of bodily fluids
12
Q
HIV / AIDS
Description
A
HIV-Positive: the virus enters the body but remains inactive
Once it becomes active it attacks and destroys T helper cells
This damage to the immune system makes the person susceptible to a range of opportunistic infections
It is the effects of these diseases that will kill a person with HIV
AIDS stands for acquired immune deficiency syndrome
13
Q
HIV / AIDS
Global Distribution
A
Worldwide Particularly: -Sub Saharan Africa -South East Asia -Latin America
14
Q
HIV / AIDS
Global Impact
A
Over 40 million people are living with HIV
Millions of new cases are discovered each year
Affects a range of people not just those in poverty
TH is an associated opportunistic infection
15
Q
HIV / AIDS
Control Measures
A
Health education
Screening of blood donations
Needle exchange schemes
16
Q
TB
Cause
A
Two species of bacterium:
- Mycobacterium tuberculosis
- Mycobacterium bovis
17
Q
TB
Transmission
A
Droplet Infection Made more likely by: -overcrowding -poor ventilation -poor health -poor diet TB can also be contracted from the milk or meat of cattle
18
Q
TB
Global Distribution
A
Worldwide Particularly in: -South East Asia -Sub Saharan Africa -Eastern Europe
19
Q
TB
Global Impact
A
Some strains are resistant to drugs
New people are infected each year
Many people may be infected but not diagnosed yet
BCG vaccine has been ruled ineffective
20
Q
TB
Control Measures
A
Contact tracing
Testing for bacteria and screening for symptoms
Long course of antibiotics
21
Q
Immune Response
Definition
A
A response to an antigen which involves the activation of leukocytes and the production of antibodies
22
Q
Antigen
Definition
A
Molecules found on the surface of cells which can stimulate the production of antibodies
23
Q
Antibodies
Definition
A
A specialised protein produced by B cells
Able to neutralise the effect of a complimentary antigen
24
Primary Defence
| Definition
Defences that set out to prevent pathogens from entering the body
25
Primary Defences
| Tears
Wash out bacteria
| Contain lysosome enzymes and antibodies to destroy bacteria
26
Primary Defences
| Skin
A tough impenetrable layer
27
Primary Defences
| Mouth
Contains good bacteria to prevent the establishment of bad bacteria
28
Primary Defences
| Nose and Lungs
Contain ciliated epithelial
29
Primary Defences
| Stomach
Highly acidic to kill potential pathogens
30
Leukocytes
White blood cells
31
Phagocytes
| Definition
Cells that can carry out a phagocytosis and ingest bacteria or small particles
Macrophages and neutrophils are both phagocytes
Non specific
32
Non Specific Immune Response
| Macrophages
Manufactured in the bone marrow
Travel in the blood as monocytes
Tend to settle in the body organs particularly in the lymph nodes where they develop into macrophages
Engulf invading pathogens
33
Non Specific Immune Response
| Neutrophils
Produced in the bone marrow
Travel in the blood
Able to squeeze out of the blood into the tissue fluid
Also found on epithelial surfaces e.g. in the lungs
Undergo phagocytosis
34
Secondary Defence
| Definition
Defences that attempt to destroy pathogens that have already invaded the body
35
Differences Between Macrophages and Neutrophils
```
Macrophages live longer in the blood
Macrophages are larger than neutrophils
Neutrophils dominate the infection site early after infection, macrophages dominate one to two days after the infection
Neutrophils have a multi-lobed nucleus
Macrophages can present antigens
```
36
Neutrophils
| Structure
Multi lobed nucleus
| Very flexible allowing them to pass through the fenestrations in capillary walls to move into the tissue fluid
37
Antibodies
| Structure
Y shape
Constant Region:
-Two heavy polypeptide chains and two light polypeptide chains
-Disulphides bridges between polypeptide chains
-hinge region to arms to spread apart when the antibodies binds to an antigen
Variable Region
-differentiates between antibodies
-complimentary shape to specific antigens
38
Neutralisation of Pathogens
Antibodies cover binding sites on pathogen preventing it from binding to a host cell
39
Agglutination of Pathogens
Antibodies cause pathogens to clump together making it easier to be engulfed by phagocytes
40
Specific Immune Response
| B Lymphocytes
- Antibodies on the surface bind to antigens on the surface of the pathogen partially activating the cell
- An activated complimentary T helper cell binds to the B lymphocyte and activates it
- The B cell clones itself producing B memory cells and activated B cells
41
Specific Immune Response
| Macrophages
- takes in pathogen by phagocytosis
- antigen presentation, takes the antigens from the pathogen and attaches them to an MHC protein which is over to the surface by exocytosis
- binds to complimentary T helper cell and activates it
42
Specific Immune Response
| T Helper Cells
- CD4 receptor on surface binds to complimentary antigens on antigen presenting macrophage
- receives signal from macrophage to activate it
- clones itself to produce T memory cells and activated T helper cells
43
Specific Immune Response
| Plasma Cells
- activated B cells differentiate to become plasma cells
- full of RER for protein synthesis
- produce vast numbers of antibodies
- antibodies are secreted by exocytosis
44
Specific Immune Response
| B Memory Cells
- remain in the body for a long time after infection
| - trigger a faster secondary immune response
45
Specific Immune Response
| T Memory Cells
- remain in the body for a long time after infection
| - trigger a fast secondary immune response
46
Specific Immune Response
| Activated T Helper Cells
- bind to complimentary B lymphocyte
| - secretes cytokines to activate the B lymphocyte
47
B cells
| Production
Produced in the bone marrow by stem cells
| Mature in the bone marrow
48
T Cells
| Production
Produced by stem cells in the bone marrow
| Mature in the thymus (in the chest)
49
Clonal Selection
| Definition
Selecting the complimentary lymphocyte to the antigen on the invading pathogen
50
Clonal Expansion
| Definition
Selected complimentary lymphocyte clones producing many more
51
Primary Response
| Definition
The pathogen is detected by the immune system and starts producing antibodies but it takes a few days for antibody activity to significantly increase
52
Secondary Response
| Definition
Memory cells are able to trigger a much faster immune response, rapidly producing large numbers of antibodies
53
Natural Immunity
| Definition
Immunity acquired through exposure to disease during the normal course of life
54
Artificial Immunity
| Definition
Immunity acquired by deliberate exposure to antigens or injection of antibodies
55
Passive Immunity
| Definition
Immunity acquired without the activation of lymphocytes
| Provided by antibodies which haven't been produced by stimulating the immune system
56
Active Immunity
| Definition
Immunity acquired by the activation of the immune system
57
Passive Natural Immunity
| Example
Maternal antibodies provided via breast milk or the placenta
| Useful while the baby's immune system is still developing
58
Passive Artificial Immunity
| Example
Injection of antibodies
59
Active Natural Immune
| Example
Antibodies and memory cells made in the immune system as a result of infection
60
Active Artificial Immunity
| Example
Antibodies and memory cells made in the immune system as a result of vaccination
61
Herd Vaccination
Large proportion of the population is vaccinated
| Reduces the risk for individuals that aren't vaccinated as the disease can't spread
62
Ring Vaccination
Vaccinating individuals in the immediate proximity of a new case of infection
Prevents the disease from spreading
63
Influenza
| Definition
Respiratory disease caused by a virus
64
Influenza
| Government Response
In the UK there is a vaccination programme for over 65s and 'at risk' groups
Specific strains of flu are vaccinated against because the virus mutates so quickly
Research is done to determine which strains of flu are likely to spread fastest in a particular year
65
New Sources of Medicine
| Microorganisms
- research into how they cause disease
- it may be possible to block receptor sites to prevent pathogens fro entering the cell
- comparing human DNA with the microorganism to identify potential drugs
66
New Sources of Medicine
| Plants
- maintaining biodiversity is important as plants that could be developed as new drugs may become extinct
- comparing human and plant DNA to identify potential drugs
67
New Source of Medicine
| Chemical Fingerprinting
New techniques allow scientists to screen natural chemicals
68
Specific Immune Response
| T Lymphocytes
- viral pathogen invades host cell which presents viral antigens on surface
- complimentary T lymphocyte binds to presented antigens
- T lymphocyte clones producing T memory cells and T killer cells
69
Specific Immune Response
| T Killer Cells
- binds to complimentary presented antigens on surface of host body cell
- secretes toxic substances e.g. hydrogen peroxide into the infected cell
- this causes lysis
- the cell bursts destroying it and the viral pathogen
70
Vaccination
| Definition
Deliberate exposure to antigenic material (using an injection) which activates the immune system triggering an immune response producing memory cells to provide immunity
71
Antigenic Material Examples
Whole, live Microorganisms
A dead pathogen
Harmless or attenuated version of the pathogenic organism
Preparation of the antigens from a pathogen
72
Nicotine
| Effects
Releases adrenalin increasing heart rate and blood pressure
Stimulates decrease in blood flow to the extremities
Makes platelets sticky increasing the risk of blood clots, thrombosis
73
Carbon Monoxide
| Effects
Reduces the oxygen carrying capacity of the blood as haemoglobin has a higher affinity for carbon monoxide than oxygen
Damages the linings if arteries
74
Tar
| Short Term Effects
Settles in the linings of the airways and the alveoli which increases diffusion distance
Can trigger allergic reactions
Airway lumen narrows restricting air flow
Paralyses cilia
Stimulates goblet cells to secrete mucus
Increased risk of infection
75
Tar
| Long Term Effects
```
Smokers cough
Irritation of airways
Damages linings of airways and alveoli
Linings replaced by scar tissue
Smooth muscle thickens permanently narrowing lumen
```
76
Effects of Smoking - Gas Exchange System
Chronic Bronchitis
Emphysema
Lung Cancer
Chronic Obstructive Pulmonary Disease
77
Chronic Bronchitis
| Description
Inflamed lining of lungs
Smooth muscle thickens
Goblet cells secrete more mucus
Damage to cilia
78
Chronic Bronchitis
| Effects
Shortness of breath
Wheezing
Persistent cough
Increased risk of lung infection
79
Emphysema
| Description
Loss of elasticity in the alveoli
Alveoli burst
Air spaces are larger reducing surface area for gas exchange
80
Emphysema
| Effects
Shortness of breath
Difficulty exhaling
Blood less well oxygenated
Fatigue
81
Lung Cancer
| Description
Carcinogens enter lung tissue cells
Mutation effects cell division controlling gene
Uncontrolled division leads to tumour
Bronchitis become blocked by cancerous growth
82
Lung Cancer
| Effects
Persistent cough
Coughing up blood
Weight loss
Chest pain
83
Effect of Smoking - The Cardiovascular System
```
Atherosclerosis
Thrombosis
Stroke
Coronary Heart Disease
Arteriosclerosis
```
84
Atherosclerosis
| Description
Carbon monoxide damages endothelium of arteries
Damage repaired by leukocytes
Encourages smooth muscle growth and deposition of cholesterol by LDLs
Deposits build up to form atheroma in the artery wall
Atheroma grows larger and penetrates endothelium
This forms a plaque sticking out into the lumen of the artery
85
Atherosclerosis
| Effects
Reduced lumen size
Restricted blood flow
Increased risk of blood clots
Reduced blood flow in coronary arteries leads to coronary heart disease
86
Thrombosis
| Description
Formation of a thrombus, a blood clot
Clots can break off and flow in the blood
Lodge in narrow arteries stopping blood flow
87
Thrombosis
| Effects
Can cause strokes
| Restricts blood flow
88
Stroke
| Description
Caused by a thrombus or a haemorrhage causing a an artery leading to the brain bursting
A death of part of the brain tissue
89
Stroke
| Effects
Sudden numbness or weakness in face, arm, leg ,one side of body
Difficulty seeing, speaking, walking, balancing
Severe headache or migraine
90
Coronary Heart Disease
| Description
Coronary arteries carry blood at high pressure increasing risk of atherosclerosis
Arteries can be narrowed by plaques
Cardiac muscle receives less oxygenated blood
91
Coronary Heart Disease
| Effects
Difficulty exercising
Out of breath easily and quickly
Chest pain
92
Arteriosclerosis
| Description
Thickening and stiffening of artery walls
| Loss of elasticity
93
Epidemiology
The study of patterns in disease and he factors that influence their spread
- identifies links between disease and risk factors
- incentivise at risk groups
- predicts future incidents of disease
94
Epidemiology
| Smoking and Disease
About half of smokers die of smoking related diseases
| Smokers are 3 times as likely to die in middle age than non smokers
95
Epidemiology
| Smoking and Lung Cancer
Stopping smoking reduces the risk of lung cancer
Smokers are 18 times more likely to develop lung cancer
25% of smokers die due to lung cancer
96
Epidemiology
| Smoking and Cardiovascular Disease
Less evident link as CVD is multi factorial
| However substances in cigarette smoke are known to increase the risk of CVD
