B-3 Infection and response Flashcards
(41 cards)
1
Q
What is a pathogen
A
- Pathogen is a microorganism that can cause infection disease
- may be bacteria, virus, protists or fungi
- Can be seen in plants or animals.
2
Q
What are the characteristic of viruses and bacteria
A
- Bacteria- very small cells- reproduce rapidly- may produce toxins that damage cells and produce toxins
- Virus- not cells- tiny- reproduce rapidly inside body live inside cells and replicate- spread- cell damage makes you feel ill- burst and release new virus
3
Q
What are the characteristics of Fungi and protists
A
- Protists- All eukaryotes- most single celled- some parasites- live on or inside organisms and cause damage
- Often carrie day vector who does not get disease
- Fungi- Single celled or body made fro hyphae- grow and penetrate human skin and surface and skin causing disease
- Can produce spores which spread to other plants and animals
4
Q
- How can pathogens spread
A
- Water- Drinking or bathing- e.g cholera.
- Air- carried in air and breathed in- cough or sneeze e.g influenza virus
- Direct contact- Touching- e.g skin. E.g athletes foot
5
Q
- What is measles
A
- Viral disease showing symptoms of fever and red skin
- Serious can be fatal with complications
- Spread through inhalation of droplets from infected persons sneezes of coughs
- Children are vaccinated against it
6
Q
- What is HIV
A
- Initially causes flu like symptoms - can feel no symptoms for years after
- Unless controlled with antiretroviral drugs it can attack immune system
- Can cause AIDS when boys immune system becomes so weak it cannot cope with infection or cares
- Spread by sexual contact or exchange of bodily fluids- e.g needles
7
Q
What is Tobacco mosaic virus
A
- Plant pathogen affecting many species of plants including tomatoes
- Causes mosiac pattern - discolouration
- Lack of photosynthesis - lac of growth
8
Q
What is Rose black spot
A
- A fungal disease where purple or black spots develop on the leave- often turn yellow and drop
- Photosynthesise reduced- growth-
- Spread in water or wind
- Treated using fungicides and removing affected leaves
9
Q
What is malaria
A
- Pathogens cause malaria are protists
- Life cycle that includes mosquito
- Causes episodes of fever- can be maya;
- Prevent vectors from breeding and using mosquito nets
10
Q
What is salmonella
A
- Food poisoning spread by bacteria - secrete toxins
- Fever, stomach cramps, vomiting and diarrhoea
- Uk most poultry vaccinated- limits spread
- Contaminated eating
11
Q
- WHAT IS GONORRHOEA
A
- STI-
- Thick yellow discharge and pain when urinating
- caused by bacteria
- Used to be easily treated with penicillin- became resistant
- Barrier method anti antibiotics
12
Q
What can be done to reduce the risk of the spread of disease
A
- Being hygienic- stop you infecting
- Destroying vectors- protists cannot be transferred
- Isolating infected individuals- stops spreading
- Vaccination- Can’t get it
13
Q
What is the non-specific defence system
A
- Skin- Barrier- antimicrobial substance- kill pathogens
- Hairs and mucus- trap practices that contain pathogens
- Trachea and bronchi- Cilla- waft mucus that contains pathogens back up
- Stomach- hydrochloric acid- kill
14
Q
What are phagocytes
A
- White blood cells
- Engulf and digest
- Foreign cells
15
Q
What role do white blood cells have on your immune system,
A
- Travel around and attack and destroy pathogens
16
Q
What are lymphocytes- Antibodies
A
- Every pathogen has unique antigens on surface
- When white blood cells come across foreign antigen they produce antibodies-
- These antibodies lock on so they can be found and destroyed by other white blood cells- try new antigens - will only lockout that one
- Antibodies produced rapidly and carried to do to all cells
- Stored as memory lymphocytes so if they come back again can be destroyed quickly
17
Q
What are antitoxins
A
-Toxins produce by the living bacteria
18
Q
What does vaccination involve
A
- Introducing small amounts of dead or inactive forms of pathogens into body
- Stimulates white blood cells to produce antibodies
- If the same disease comes back the memory lymphocyte will know the antibody needed
19
Q
How does vaccination prevent illness on a population level
A
- If large proportion of population is immune the spread is very limited
- Disease may even disappear
- Herd immunity
- Can re-appear
- Whopping cough- 1980s- safety concerns- substantial number does
20
Q
- What are the pros and cons of vaccines
A
Pros-
- Helped control lots of disease e.g polio, whooping cough, mumps
- Eradicated small pocks and 95% of polio now gone
- Large outbreaks and be prevented if vaccinated
Cons
- DOn’t always work
- Can get a bad reaction- rare
21
Q
What are antibiotics
A
- Medicines that help cure bacterial disease by killing infective bacteria inside body.
- Specific bacteria treated by specific antibiotic
22
Q
What uses to antibiotics and other medicine have in treating disease
A
- -Actually kill or prevent growth the bacteria without killing body cells
- Different for each bacteria
- Cannot kill viruses
23
Q
What is the issue with finding drugs for viruses
A
- Viruses reproduce using body own cells which makes it difficult to kill them with killing your own body
24
Q
What has the use of antibiotics done
A
- Greatly reduced the number of deaths from communicable disease caused by bacteria
25
- `what are the steps in bacteria becoming resistant to antibiotics
- Bacteria can mutate-become resistant
- If have infection some bacteria may be resistant to antibiotics
- Only the non-resistant strain survives
- This then reproduces and increase in number-
- Could cause serious infection that antibiotics can treat
e.g MRSA caused wound infections and is resistant to methicillin
26
What can be done to stop down the rate at which resistant strains develop
- Doctors can stop overprescribing
| - Finish the whole course of antibiotics
27
What are painkillers
- Used to treat symptoms, pain, and do not kill pathogens
28
- How can plants be used to create drugs
- Plants produce variety of chemicals to defend themselves
- Can be used as drugs to treat humans or relive symptoms
- Some can be extracted from microorganisms
- Most are made by chemists but they are still used today
29
- What examples of plants being used for medication can be seen today
- Aspirin- painkiller to lower fever. Found in willow
| - Digitalis- Used to treat heart conditions- Found in Foxgloves
30
What was Alexanders Flemming's discovery
- Was clearing out petri dishes containing bacteria
- One of dishes had mould, but area around mould was free of bacteria
- Mould called penicillium notatum was producing substance that killer bacteria
- Penicillin
31
What are the three stages in drug testing- breif
- Pre-clinical 1- tissue
- Pre-clinical 2- animals
- Clinical- humans
32
Describe the first stage of drug development
- Preclinical-
- Tested on human cells and tissues
- Can't use humans cells or tissue to test drugs that affect whole or multiple systems
- E.g Blood pressure drug has to be done on whole animal
33
- Describe the second stage in drug development
- Pre-clinical 2
- Animals
- Test efficiency, toxicity and dosage
- Law in Britain means new drug has to be tested on two live animals
34
What are efficiency, toxicity and dosage - drugs
- Efficiency- Wether it works or not and produces desired effect
- Toxicity- How harmful drug is
- Dosage- Concentration and frequency at which the drug should be given
35
What are contrasting views on Animal testing
- Some people say its cruel and wrong.
- Animals don't get the choice
- Animals are different to humans so its pointless
- Some say its the safest way
- Better for animals to be harmed than humans
36
What is the third stage in Drug development
- Clinical testing
- Tested on voluntary, healthy volunteers- side effects
- Starts with very low dose
- optimum dose found with further trials
- If Safe it gets tested on sufferers on illness-
- Goes through peer review and published
37
What is an optimum dose
- A dose that produces the greatest effect with the fewest side effect
38
What is a placebo
- A substance that is like the drug but does nothing
39
What is the placebo effect
- Where someone expects the treatment to work and feel better, even though nothing is happening
40
What is meant by a blind trial
- Patients don't know if they are getting the drug or placebo
- Allows to compare actual results to pleb results
41
What is a double blind trial
- Where neither the patient to the doctor know wether or not they have been given the placebo till the end
- stops sub-conscience influencing of testers
