b6.3 - immunity/ bacteria Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

vaccination

A
  • given a little bit of of inactive or dead pathogen
    -correct lymphocytes produce antibodies and destroy pathogens
  • some lymphocytes become memory cells
  • when live pathogens of the same type infect you your immune system can protect you immediately due to memory cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

how are vaccines given

A

injection
orally
nasal sprays

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

vaccine (primary vs secondary response)

A

secondary
- fast
- many antibodies
as you ahve memory cells so start with more cells and antibodies can be made faster

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

mass vaccination

A

if everyone is vaccinate they can destroy the pathogen fast and not get symptoms
if not enough vaccinated they can continue to carry and spread it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

why do you need boosters

A

memory cells sometimes don’t last so need a boost to make more memory cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

bacteria growth over time

A

lag phase
- no reproduction
- copy dna and proteins within single cells
exponential growth
- due to correct conditions
stationary phase
- resources become scarce
- die at same rate as reproduction
death phase
- bacteria poisoned by build up of toxins in the culture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

binary fission

A
  • circular dna strand replicates
  • circular strands migrate to opposite ends of cells
  • cytoplasm replicates and divides
  • cells divide in two
  • identical daughter cells made
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

how to calculate no. of bacteria in a population

A

1calculate no. divisions in the asked hours
- eg if it asks how many in 6h and it gives you 3 in 1h it’ll be 18 divisions
2calculate no. bacteria
- everytime it reproduces it doubles
- bacteria at start x2^no. divisions
3how long it takes to reach a given no. bacteria
- log2 x given no. bacteria
- times this by the mean division time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

aseptic techniques to grow microorganisms

A
  • sterilise, petri dish and agar
  • Work close to a roaring flame
  • heat the inoculating loop
  • Let the loop cool, without putting the loop back on the table
  • Open the tube of bacteria and flame the neck of the tube - Dip the loop in the tube
  • Lift the petri dish lid a little - draw a line down the plate using the loop
  • label the dish and seal it with tape
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

why do you sterilise and heat and not leave on the table and work near to a bunsen

A

to kill any contaminating bacteria (clean it)
- create convection current lifting unwanted microbes away from working area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

why use an incubation temperature not above 25°?

A

so we don’t grow pathogenic bacteria that can cause harm to humans.
- We only grow bacteria denatures at 25° so can’t survive in the human body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

how do antibiotics kill bacteria

A

by interfering with bacterias metabolism, e.g. processes that make the bacteria cell wall

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

if not cell wall in bacteria why can it die

A

if in hypotonic solution it could lyse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

antivirals

A

A drug that treats viruses
- it prevents reproduction.
- It only slows down, doesn’t kill it
- because of the virus is in the host cells to kill the virus you killed the host cells, so it’s difficult to not damage cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

antiseptics

A

antimicrobial substances applied to human tissue or skin
- different antiseptic skill, different pathogens,
e.g. alcohol/iodine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

disenfectants

A

Solutions that destroy a micro organism on the surface of nonliving things

17
Q

how to investigate the strength of disenfectants

A
  • wash hands/ wear gloves
  • divide the sealed plate into six equal sections, using a pen,
  • use the sterile, forceps, dip one paper disk into each disinfectant
  • put the paper desk, intro respective section on the agar plate, container bacteria
  • dip one disc into water this is a control
  • make sure disks do not touch each other
  • reseal the plate with tape and incubate it.
18
Q

preclinical testing (step 1)

A
  • tested using computer models and human cells grown in the laboratory
  • scientists check side-effects and efficacy of the drug.
  • Many drugs fail because they damage cells or don’t work
19
Q

preclinical trials (step 2 )

A

drug tested on live animals
- Involves giving a know amount to animals and monitoring them for side effects

20
Q

clinical trials (phase 1)

A
  • drug tested on a small number (20–80) of healthy volunteers
  • very low doses of the drug in at the start and volunteers monitored for side-effects.
  • If deemed safe further tests carried out to find the optimum dose
21
Q

clinical trials (phase 2)

A
  • The drug is seher, my small sample (100–300) volunteers, who suffer from the condition
  • To look for efficacy & side effects
22
Q

clinical trials (phase 3)

A
  • drug tested on a large number of people (1000–5000) who suffer from the condition
  • To monitor, drug, effectiveness, side-effects, safety and adverse reactions to long-term use
  • trials reviews by medical professionals and then published
23
Q

drugs from plants/ microbes

A
  • heart drug came from foxgloves
  • Aspirin comes from Willow trees
  • Penicillin discovered by Alexander Flemmjng
24
Q

double blind trial

A

volunteers and patient, randomly, allocated
so neither doctor or patient know if they take the drug or the placebo
- minimises, the placebo effect, ensured results cannot be influenced by people in the trial

25
Q

why is single blind not effective

A

The doctor who knows what drug is being taken, may give away, clues about what the patient taking without realising it
- this is the observer bias

26
Q

cost of developing drugs

A
  • find this may take years to find the right, chemical
  • the raw materials, maybe rare or difficult to make
  • the volunteers need to be paid for time and risking health
  • Many patients need to be tested for several years to check it works
  • permission to sell the medicine is only given if there’s good enough evidence it’s safe and effective