Topic 3- Infection and Response. Flashcards

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

what are pathogens?

A

they are microorganisms that enter the body and cause disease.

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

what do pathogens cause?

A

they cause communicable (infectious) diseases.

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

what can be infected by pathogens?

A

both plants and animals can be infected.

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

what are the four main types of pathogens?

A
  • bacteria.
  • viruses.
  • protists.
  • fungi.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what are the ways that pathogens can spread?

A
  • water- drinking or bathing in dirty water.
  • air- can be carried in the air and can be breathed in. some can be carried in droplets made when you sneeze or cough.
  • direct contact- can be picked up by touching surfaces they are on (e.g: the skin).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

how can the spread of diseases be reduced or prevented?

A
  • being hygienic- washing hands.
  • destroying vectors - vectors are organisms that spread diseases.
  • isolation infected individuals- keep them away from other people.
  • vaccination- can stop people and animals from getting a communicable disease.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are bacteria?

A

very small living cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

how fast can bacteria reproduce?

A

can reproduce rapidly inside your body.

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

how does bacteria make you feel ill?

A

they produce toxins which is poisons- they can damage your cells and tissues.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what are the two diseases that are bacterial diseases?

A
  • salmonella.

- gonorrhoea.

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

what is salmonella?

A
  • it is a type of bacteria that causes food poisoning.
  • people can suffer from fever, stomach cramps, vomiting and diarrhoea.
  • these are caused by toxins from the bacteria.
  • you can get it… if food is already containing it or it’s been cooked at a place where’s t contains it.
  • in ik- poultry (chickens/turkeys) are given vaccinations.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is gonorrhoea?

A
  • it is caused by a bacteria.
  • it is a STD.
  • they are passed on by sexual contact.
  • pain with they urinate. a thick yellow/green discharge from the vagina/penis.
  • used to be treated with antibiotics (penicillin) now it is resistant to penicillin- new strains.
  • to stop the spread- treat win other antibiotics or use barrier methods.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

are viruses cells or not?

A

they are not cells.

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

how do viruses reproduce?

A

they reproduce rapidly.

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

where do viruses live?

A

inside your cells.

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

what do viruses do inside your cells?

A

they make lots of copies of themselves.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what happens to the cell after they make lots of copies of themselves?

A

the cells usually burst which releases all the new viruses.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what makes you ill?

A

the cell damage.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what viruses can cause different diseases?

A
  • measles.
  • HIV.
  • tobacco mosaic virus.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what is measles?

A

it is spread by droplets form an infected person’s sneeze or cough. they develop a red skin rash and have symptoms of a fever. it can be very serious as people can die if they are any complications. therefore a lot of people are vaccinated against measles when they are young.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what is HIV?

A

it is spread by sexual contact or by exchanging bodily fluids. this can happen when people share needles when taking drugs. for a few weeks HIV causes flu-like-symptoms. it is controlled by antiretroviral drugs. this stops virus copying itself in the body. if not controlled it attacks the immune system. if immune sytem damaged then it cannot cope with other infections- this stage is called late HIV infection or AIDS.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what is tobacco mosaic virus?

A

it is a virus that affects many species of plants. (e.g:tomatoes). causes part of the leaves to become discoloured which gives them a mosaic pattern. the discoloured leaves have less chlorophyll to absorb light. this means less photosynthesis happens in the leaves so plant can’t make enough food to grow.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is a rode black spot?

A

it is a fungal disease. the fungus causes purple/black spots on the leaves of rose plants. the leaves turn yellow and drop off. this means less photosynthesis can happen so less growing. it is spread by water or the wind. gardeners can treat this using fungicides or strip the affected leaves off the plant. these leaves need to be destroyed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is malaria causes by?

A

a protist.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

where does part of the protist’s life cycle take place?

A

takes place inside the mosquito.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

how does a mosquito spread the malaria?

A
  • the mosquito picks up the protist when they feed on an infected animal.
  • the mosquito doesn’t get malaria.
  • they pass on the protist to the other animals when they bite them.
  • the animals get malaria.
27
Q

what does malaria cause?

A

it causes repeating causes of fever- people can die.

28
Q

how can the spread of malaria be reduced?

A

stopping the mosquitoes from breeding.

29
Q

how can people be protected from mosquitoes?

A

using mosquito nets.

30
Q

what features from the human body stop nasty things from entering the body?

A
  • the skin.
  • nose hairs.
  • mucus (snot).
  • cilia (hair-like structures).
  • Stomach acid.
31
Q

what does the skin stop?

A

it stops pathogens getting inside. it also releases substances that kill pathogens.

32
Q

what do nose hairs stop?

A

they trap particles that could contain pathogens.

33
Q

what does the mucus stop?

A

the trachea and bronchi release mucus to trap pathogens.

34
Q

what does the cillia do?

A

the trachea and bronchi are lined with cilia. they move the mucus up to the back of the throat where it can be swallowed.

35
Q

what does the stomach acid do?

A

it makes hydrochloric acid- this kills pathogens in the stomach.

36
Q

what can your immune system attack?

A

it can attack pathogens.

37
Q

what is the most important part of the immune system?

A

the white blood cells.

38
Q

what are the three lines of attack in the immune system?

A
  • phagocytosis.
  • producing antibodies.
  • producing antitoxins.
39
Q

what is phagocytosis?

A

it is when the white blood cells engulf (surround) pathogens and digest them.

40
Q

what happens when producing antibodies?

A

every invading pathogens has a unique molecules on its surface= antigen. when some types of white blood cells come across a foreign antigen they will start to make antibodies. antibodies lock onto invading pathogens. the antibodies made are specific to that type of antigen- won’t lock to any other. antigens make sure the pathogens can be found and destroyed by other white blood cells. if the person is infected with the same pathogen again the white blood cells will rapidly make antibodies to kill it- means they will be naturally immune and won’t get ill.

41
Q

what happens when producing antitoxins?

A

the antitoxins stop toxins produced by the invading bacteria from working.

42
Q

what does vaccination protect us from?

A

from future infections.

43
Q

what does vaccination involve?

A

it involves injecting small amounts of dead or inactive pathogens into the body.

44
Q

what do these pathogens have on their surface?

A

antigens.

45
Q

what do the anitgens cause?

A

it causes the white blood cells to produce antibodies to attack the pathogens.

46
Q

what happens if you are infected with the same pathogen?

A

your white blood cells quickly produce lots of antibodies. these antibodies kill the pathogen so you don’t become ill.

47
Q

what are the advantages of vaccination?

A
  • they have helped control lots of communicable diseases that used to be common in the UK (polio).
  • a big outbreak of disease is called an epidemic. they can be prevented if lots of people are vaccinated. even people who aren’t vaccinated are unlikely to catch the disease because there are fewer people able to pass it on.
48
Q

what are the disadvantages of vaccination?

A
  • vaccines doesn’t always work- sometimes they don’t give you immunity.
  • can have bad reaction to a vaccine (swelling or fever).
49
Q

what has drugs got to do with fighting diseases?

A
  • some drugs can help get rid of symptoms. (it doesn’t kill pathogens).
  • other drugs can cure the problem.
50
Q

what does antibiotics kill?

A

bacteria.

51
Q

what has the uses of antibiotics done?

A

it has massively reduced the number of deaths from communicable diseases caused by bacteria.

52
Q

what doesn’t antibiotics do?

A

it doesn’t destroy viruses.

53
Q

how do viruses reproduce?

A

they use your own body cells, making it very difficult to develop drugs that destroy the virus without killing the body’s cells.

54
Q

what can bacteria become?

A

resistant to antibiotics.

55
Q

what can bacteria do?

A

they can mutate (change).

56
Q

what can some of these mutations cause the bacteria to become?

A

to become resistant to an antibiotic. resistanr strains of bacteria (e.g: MRSA) have increased as a result of natural selection.

57
Q

what do plants produce?

A

they produce chemicals to defend themselves against pests and pathogens. some of these chemicals can be used as drugs to treat human diseases or relieve symptoms.

58
Q

examples of drugs that has a come from a plant?

A
  • aspirin- used as a painkiller, made from a chemical found in willow.
  • digitalis- used to treat heart conditions, made from a chemical found in foxgloves.
59
Q

some drugs come from microorganisms, for example:

A

pencillin- Alexander Fleming found that a type of mould (Pencillium) makes a substance that kills bacteria. this was substance is called penicillin and now used as an antibiotic.

60
Q

where are new drugs made today?

A

new drugs are made by the pharmaceutical industry (companies that make and sell drugs.) there are made by chemists in labs. the process still might start with a chemical taken from a plant.

61
Q

what are the different stages in developing new drugs?

A
  • preclinical.

- clinical testing.

62
Q

what happens in the preclinical testing?

A

1) drugs are first tested on human cells and tissues in the lab.
2) then tested on live animals to find out…
- the efficact (whether the frug works and has effects you are looking for).
- the toxicity (how harmful it is and any side effects).
- the dosage (the concentration of the drug that it works best and how often it should be taken).

63
Q

what happens in clinical testing?

A

1) if the drug passes on animals then it is tested on human volunteers in a clinical trial.
2) first testes on healthy volunteers- to make sure it doesn’t have any harmful side effects when the bdy is working normally.
3) at the start of the trial, a very low dose is given- then increase a little at a time.
4) if these result are good, they can be tested on patients.
5) the optimum dose is found - it is the dosage of drug that is the most effective and has a few side effects.
6) to test how well the drug work, patients are put into two groups: group 1 has the drug and group 2 had a placebo- it doesn’t do anything.
7) the doctors compare results to see if it makes a real differences.
8) clinical trials are blind- the patient doesn’t know.
9) sometime it can be double-blinded- patient or the doctor doesn’t know.
10) results are published until they have been through peer review which helps them prevent false claims.