Topic 5 - Health, disease and development of medicines Flashcards
(93 cards)
1
Q
What is health
A
State of complete physical, mental and social well-being and not merely absence of disease or infirmity
As defined by World Health Organisation (WHO)
2
Q
What are the two types ofg disease
A
- Communicable
- Non-communicable
3
Q
What is a communicable disease
A
- Disease passed from person to person
- Caused by pathogen
4
Q
What is a non-communicable disease
A
A disease that is:
* Not passed from person to person
* Not caused by a pathogen
5
Q
What is a pathogen
A
An agent causing communicable disease - an infectious agent
6
Q
What are types of pathogens
A
- Viruses
- Bacteria
- Fungi
- Protists
7
Q
Why can the presence of one disease lead to higher susceptibility to other diseases
A
A disease may weaken an individual’s immune system making them increasingly susceptible to other infections
8
Q
What type of disease is malaria
A
Protist disease
9
Q
What are symptoms of malaria
A
- Bouts of fever
- Damage to blood
- Damage to liver
10
Q
How is malaria spread
A
Through a vector such as mosquito
11
Q
How can malaria be prevented
A
- Using mosquito nets to avoid being bitten
- Killing mosquitoes with insecticides
- Draining stagnant water where mosquitoes lay their eggs
12
Q
What type of disease is chalara ash dieback
A
Fungal disease
13
Q
What are symptoms of chalara ash dieback
A
- Loss of leaves
- Dieback of growing shoots of tree
- Lesions in bark
14
Q
How is chalara ash dieback spread
A
Through air
15
Q
How can chalara ash dieback be prevented
A
Collect leaves and then burn or bury them
16
Q
What type of disease is cholera
A
Bacterial disease
17
Q
What are symptoms of cholera
A
Diarrhoea, vomiting
18
Q
How is cholera spread
A
By drinking water or washing in water that has been contaminated with infectious faeces
19
Q
How can cholera be prevented
A
- Access to clean water
- Improved sanitation (sewage disposal etc.)
20
Q
What type of disease is tuberculosis (TB)
A
Bacterial disease
21
Q
What are symptoms of tuberculosis (TB)
A
Lung damage, chesty cough, wheezing
22
Q
How is tuberculosis spread
A
In air
23
Q
How can tuberculosis be prevented
A
- Improved hygeine (washing hands, sneezing in tissues etc.)
- Infected individuals should avoid crowded areas
- Increased ventilation in individual’s home
24
Q
What type of disease is stomach ulcers
A
Bacterial disease caused by Helicobacter pylori
25
What are symptoms of stomach ulcers
Stomach pain, vomiting, nausea
26
How is stomach ulcers spread
Orally by eating infected foods or drinking infected water
27
How can stomach ulcers be prevented
* Access to clean water
* Improved hygiene
* Improved sanitation (sewage disposal etc.)
28
What type of disease is Ebola
Viral disease
29
What are symptoms of ebola
Fever, diarrhoea, vomiting, internal bleeding
30
How is Ebola spread
Direct contact with bodily fluids (e.g. blood, semen, saliva, mucus, vomit)
31
How can ebola be prevented
* Improved hygiene
* Isolating infected individuals
* Sterilisation of outbreak areas
32
Describe the lytic cycle
* Virus binds to receptor on host cell
* Virus inserts its genetic material into host cell
* Virus is replicated - uses host cell machinery/organelles to produce viral genetic material and viral proteins
* Viral components are assembled into new viruses
* Viruses are released and host cell lyses/bursts
33
Describe the lysogenic cycle
* Viral genetic material integrates itself into host cell DNA and becones a provirus
* Provirus is replicated along with host cell genetic material, cell divides and provirus DNA is transferred to daughter celld
34
What type of disease is HIV
Viral disease
35
How are HIVs transmitted
Through bodily fluids sexually (STD) or through share of needles
36
What do HIVs do to body
* Destroy CD4+ lymphocytes, they weaken immune system
* HIVs make person classified as having AIDS (acquired immune deficiency syndrome)
37
What do HIVs make the person susceptible to
Opportunistic infections such as Mycobacterium tuberculosis
38
How can spread of HIV be reduced
* Use of condoms and protected sex
* Needle exchange
* Screening blood for HIV
* Deterring infected mothers from breastfeeding
39
40
What type of disease is Chlamydia
Bacterial disease
41
How is Chlamydia spread
Through sexual contact or direct contact with infected genital fluids
42
What does Chlamydia do the person infected with it
Can result in infertility
43
How can transmission of Chlamydia be reduced
* Use of condoms and protected sex
* Screening
44
What are physical lines of defence against pathogens in plants
* Cell walls made of cellulose that make it difficult for pathogens or pests to penetrate
* Plant leaves have waxy cuticle which is waterproof physical barrier
* Some plants have hair or spines
45
What are chemical lines of defence against pathogens in plants
* Some plant chemicals have an unpleasant taste and unpleasant small
* Some plant chemicals have antimicrobial or antibacterial properties
46
46
Why are chemicals produced by plants useful
Produce physiological effects on body so can be used in medicines to treat disease
47
How can plant diseases be detected and identified in the field
* Observation of symptoms. e.g. Chalara ash dieback causes bark lesions. Books and online resources aid identification
* Analysis of distribution of infected plants can indicate type of pathogen involved and its mode of transmission e.g. airborne
* Changing environmental conditions to eliminate other causes such as nutrient deficiencies or water-logged soils
48
How can plant diseases be detected and identified in the lab
* Detection of foreign antigens in sample of plant tissue using monoclonal antibodies
* Analysis of DNA to identify any pathogen DNA in tissue sample
49
What is the first and second line of defence against pathogens in humans
First line of defence - barriers against the entry of pathogens into the body
Second line of defence - immune system
50
What are barriers against the entry of pathogens into the body
* Mucus secreted by goblet cells traps pathogens
* Cilia of ciliated epithelial cells move and remove mucus and pathogens out of body
* Keratin (protein) in the skin is waterproof (physical barrier)
* Lysosyme (enzyme) in tears and saliva destroys bacterial cell wall and kills bacteria (antibacterial property) (chemical barrier)
* Hydrochloric acid in stomach has low pH that kills pathogens (chemical barrier)
51
How does immune system play a role as line of defence against pathogens in humans
* Phagocytes are type of white blood cells, they engulg pathogens by phagocytosis
* B lymphocytes release antibodies with a shape complementary and specific to antigen of pathogen
* B memory lymphocytes are produced in the primary immune response and are in the secondary immune response to produce more antibodies faster
* People might develop fever
52
Describe the process of vaccination/immunisation
* Dead/attenuated pathogen, containing the antigen is injected into person
* Vaccination stimulates primary immune response and B lymphocytes are activated and release antibodies with a shape complementary and specific to antigen of pathogen
* B memory lymphocytes are also formed in the primary immune response
* On infection/second exposure, b memory lymphocytes are activated producing more antibodies faster - this is secondary immune response
53
What is herd immunity
When a large number of individuals in a population are immunised/vaccinated and transmission of disease is limited
54
What are advantages of vaccination
* Herd immunity
* Helps prevent epidemics and pandemics
55
What are disadvantages of vaccinations
* Side effects
* Allergic reactions
56
What is an antibiotic
* Substance that kills or inhibits cell process of bacteria (no effect on viruses)
* No effect on cells in host organism
* Produced by living organisms e.g. fungi
57
What are aseptic techniques
* Disinect working surface before and after use
* Only lift lids of agar plates partially and for as little time as possible
* Work carefully near Bunsen burner to provide convection current
* Only dispose of used agar plates after they have been autoclaved
58
What is the process of studying antibacterial properties in plants
1. Extract is made from plant
2. Extract is then placed on paper disc then disc is placed on agar plate with bacteria
3. Control used is paper disc plus solvent only
4. Incubate temperature between 20 and 30 degrees, to prevent growth of human bacteria, overnight
5. Calculate the area of zone of inhibition using A = π r^2
6. The tronger the antibacterial property is the larger area of the zone of inhibition will be
7. Repeat this and calculate mean
59
What are the stages in developing in new medicines
* Discovery
* Development
* Preclinical testing
* Clinical testing
60
What are preclinical trials
Testing drug on cell culture, tissue culture or animals to determine its toxicity
61
What are the three phases of clinical trials
* Phase 1 - Testing on healthy volunteers
* Phase 2 - Testing on small number of individuals with medical condition
* Phase 3 - Testing on large number of individuals with medical condition
62
What are reasons for phase 1 of clinical trials
* Using different doses to determine safe dose
* To determine side effects
* To determine how the drug is metabolised
| Testing on healthy volunteers
63
What are reasons for phase 2 of clinical trials
* To see whether drug is effective in treating medical condition
* To determine less-common side effects
| Testing on small number of individuals with medical condition
64
What are reasons for phase 3 of clinical trials
To gather more data for statistical analysis
65
Describe the processes of preclinical and clinical trials
| (6 marker)
**Preclinical trial** - testing on cell culture/tissue culture/animals to determine toxicity
**Clinical trials**:
* Phase 1 - Testing on healthy volunteers to determine safe dose, side effects and how drug is metabolised
* Phase 2 - Testing on small numer of individuals with medical condition to see whether drug is effective in treating medical condition and to determine less-common side effects
* Phase 3 - testing on large number of individuals with medical condition to gather more data for statistical analysis
66
What are placebos
Substance that appears just like real drug but has no effect on recipient
67
What is a blind trial and why are they done
* Where participants don't know whether they are receiving new drug or placebo
* Prevents patient's bias affecting results
68
What is double-blind trial and why is it done
* Neither participants nor doctors know who is receiving new drug or placebo
* Prevents bias from doctors when analysing results
69
How can monoclonal antibodies be produced
* Inject antigen of pathogen into mouse/rodent
* Collect B lymphocytes from it
* Fuse B lymphocytes with myeloma cell to produce hybridoma
* Hybridoma will produce monoclonal antibodies with shape complementary and specific to antigen of pathogen
* Isolate the antibodies
70
What are uses of monoclonal antibodies
* Locating position of cancers/treatment of cancetr
* Locating position of blood clots
* Pregnancy testing
71
How can monoclonal antibodies be used to diagnose cancer
* Monoclonal antibodies tagged to radioactive substance
* Monoclonal antibodies injected into patient's blood stream
* Monoclonal antibodies bind to tumour markers on cancer cells
* Emittted radiation is detected using specialised scanner anablind doctors to determine location of cancer cells
72
How can monoclonal antibodies be used to treat cancer
* Monoclonal antibodies attached to anti-cancer drug
* Monoclonal antibodies injected into patient's bloodstream
* Monoclonal antibodies binds to tumour markers on cancer cells
* Anti-cancer drug destroys cancer cells
73
How can monoclonal antibodies be used to locate blood clots
* Monoclonal antibodies tagged to radioactive substance
* Monoclonal antibodies target and bind to specific proteins in blood clots
* Radiation emitted by monoclonal antibodies is detected enabling location of blood clots to be identified
74
How do test sticks check if a woman is pregnant
**If pregnant:**
* hCG in urine binds to monoclonal antibodies attached to blue bead
* Monoclonal antibodies with hCG diffuse up dipstick
* Monoclonal antibodies fixed to stick bind to hCG
* Blue line forms
**If not pregnant:**
* No hCG in urine so blue line is not formed
75
Give examples of non-communicable diseases
* Many forms of cancer
* Diabetes
* Some lung and liver diseases
* Diabetes
* Cardiovascular disease
76
What factors can affect risk of developing non-communicable disease
* Lifestyle factors e.g. diet, excerciese, alcohol, smoking
* Environmental factors e.g. exposure to pollution
* Genetics e.g. alleles that increase risk of cancer
77
Describe how exercise affects the risk of some non-communicable diseases
* Regular exercise decreases fat stores, reducing obesity (risk factor of cardiovascular disease and type 2 diabetes)
* Decreases heart rate, recovery time and blood pressure, lowering risk of cardiovascular disease
78
Describe how diet affects the risk of some non-commumicable diseases
* Diet high in saturated fat raises blood cholesterol levels, increasing deposition of fatty deposits in arteries so greater risk of CVD
* Obesity and consumption of large amounts of simple sugars increases risk of type 2 diabetes
* Malnourishment increases risk of deficiency diseases
79
Describe what happens in cardiovascular disease
* Fatty deposits such as cholesterol and build up in arteries into fibrous plaque
* Fobrous plaque ruptures and blood cells called platelets clot to form a thormbus
* This prevents oxygen from being delivered to tissues
* If this occurs in heart it can lead to heart attack
* If this occurs in brain it can lead to stroke
80
How can cardiovascular disease be treated
* Stents can be inserted into arteries to keep them open
* Drugs such as statin can be used to lower blood cholesterol
* Other drugs such as warfarin can be used to reduce chances of blood clots
* Lifestyle changes such as balanced diet and more exercise
81
How can type 2 diabetes be treated
Balanced diet and more exercise
82
How can type 1 diabetes be treated
Insulin injections
83
What happens in type 1 diabetes
Pancreas does not produce sufficient insulin so blood glucose after meal remains high. In some cases type 1 diabetes is genetic or inherited
84
What happens in type 2 diabetes
Cells do not respond to insulin and are insulin resistant, this means glucose will not be moved to liver cells to be converted to glycogen. This means blood glucose remains high after meal. Obesity will remain high after meal
85
Explain how the pancreas regulates blood glucose levels
* When blood sugar is high (after a meal) pancreas releases insulin into bloodstream
* Insulin causes glucose to be moved into liver cells where it is converted to glycogen
* This causes blood glucose levels to fall
* When blood glucose is low (hunger) pancreas releases glucagon into bloodstream.
* Glucagon causes glycogen in liver to be converted back into glucose and released back into bloodstream
* This causes blood glucose levels to rise
86
Give examples of deficiency disease
* Scurvy (Vitamin C deficiency)
* Anaemia (iron deficiency)
87
What is Body Mass Index (BMI)
Value based on height and mass used to categorise individual as underweight, overweight or obese
88
How is BMI calculated
BMI = mass (kg) / (height m)2
89
How is an individuals waist to hip ratio calculated
Waist-to-hip ratio = waist circumference (cm) / hip circumference (cm)
90
How does alcohol affect risk of some non-communicable diseases
* Alcohol raises blood pressure thus increasing risk of cardiovascular disease
* Toxic products in alcohol can cause mutations to DNA increasing risk of cancer
91
How does smoking affect risk of some non-communicable disease
* Nicotine raises heart rate increasing risk of cardiovascular disease
* Carbon monoxide lowers ability of red blood cells to carrt oxygen, heart rait increases increasing risk of cardiovascular disease
* Carcinogens in tar can cause mutations to DNA increasing risk of cancer
92
