B3: infection and response Flashcards Preview

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Flashcards in B3: infection and response Deck (45):
1

Pathogens

•Microorganisms that enter the body and communicable cause disease that spread to easily
•Animals and plants can be infected
• release toxins and attack cells

2

Bacteria

•Very small Cells
•Reproduce rapidly inside your body
•Produce toxins - making you ill
•Damage your cells and tissues

3

Viruses

•Are NOT cells
•Reproduce rapidly
•Live inside your cells and replicate themselves
•Take I’ve hosting cells

4

Protists

•Eukaryotes cell
•Some are parasites
•Often transferred to the organism by a vector which doesn’t get the disease it’s self e.g. mosquito

5

Fungi

•Grows and penetrates the human skin and surface of plants causing disease
•Spread by spores

6

How are pathogens spread?

•Water - picked up by drinking or bathing in dirty water e.g. cholera

•Air - carried in the air and can be breathed in , some are carried in air droplets produce when you cough or sneeze

•Direct contact - picked up by touching contaminated surfaces , including the skin

7

Measles

•Viral disease
•Spread by droplets from and infected persons sneeze or cough
•Develop red skin rash and signs of fever
•Can be fatal if there are complications - pneumonia or encephalitis
•Most people are vaccinated

8

HIV

•Is a virus
•Spread by sexual contact or exchanging body fluids such as blood
•Cause flu-like symptoms for a few weeks then the person doesn’t experience any symptoms for many years - during this time HIV can be controlled with antiretroviral drugs stopping the virus from replicating

•Attached immune cells
•Immune System is badly damaged and can’t fight off infections or cancers - late stage HIV or AIDS

9

TMV(tobacco mosaic virus)

•virus
•affects plants
•causes mosaic pattern on leaves of the plants - parts of of the leaves become discoloured
• discolouration means the plant can’t carry out photosynthesis ad well
• virus affects growth

10

Rose black spot

•Fungal diseases
•Causes purple or black spots to develop of the leaves of rose plants
• leaves can turn yellow and drop off
•less photosynthesis can happen - plants done grow very well
• spreads through the environment in water or by wind
•treated by using fungicides and by striping the plant of it’s affected leaves

11

Malaria

•Disease caused by a protist
•part of the protist life cycle takes place in the mosquitos- the vectors
• every time the mosquito feeds on another animals it infects a it by inspecting the protist into the animals blood vessels
• causes repeating episodes of fever
• spread can be reduced by stopping mosquitos from breeding - protected by using insecticides and mosquito nets

12

Salmonella

•Bacterial disease
•Causes food poisoning
•Infected people can suffer from fever , stomach cramps , vomiting and diarrhoea
•Symptoms are caused by toxins that the bacteria produce
•You can get it but eating contaminated food

13

Gonorrhoea

•Bacterial disease
•Sexually transmitted disease
•Passed in by sexual contact
•Symptoms are Pain when they urinate and yellow or green discharge from vagina or the penis
•Originally treated with an antibiotic but had become resistant to it
•To prevent spread people can be treated with antibiotics and should use Barrier methods of contraption

14

Reduce or prevention on disease

Being hygienic - simple hygiene measures, washing hands before preparing food etc

Destroying vectors - by getting rid of organisms that spread the diseases you can prevent the disease from spreading

Isolating infected individuals

Vaccination - the person can not develop the infection and then pass it on to someone else

15

Body’s Defense system- Skin

•Acts as a Barrier to pathogens
•Secretes antimicrobial substances which kill pathogens
•Skin looses layers and removed the bacteria with them

16

Body’s Defense system- Nose

•Hairs and mucus in your nose trap particles that could contain pathogens

17

Body’s Defense system- Teaches and bronchi

•Secrete mucus to trap pathogens

18

Body’s Defense system- Trachea

•Lined with cilia which waft the mucus up to the back of the throat where it can be swallowed

19

Body’s Defense system- stomach

•Produces hydrochloric acid
•Kills pathogens that make it that far from the mouth

20

Immune system

•Kicks in to destroy pathogens that make it into your body

•Most important part of the immune system is the white blood cells

21

White blood cells

•Travel around in your blood patrolling for microbes
•When they come across the microbe they have three lines of attack
-Consuming
-Producing antibodies
-Producing antitoxins

22

White blood cells three lines of attack

•Consuming the pathogen
-WBC engulf foreign Cells and digest them - phagocytosis
•Producing antibodies
-Every invading pathogen has antigens on its surface so the WBC will start to produce proteins called antibodies to lock into the invading cells so that they can be found and destroyed by they WBC
-The antibodies produced are specific to the antigen
Produces rapidly
- memory cells remember the pathogen if the person is infected again and will be immune to that pathogen
•producing antitoxins
- contract toxins produced by the invading bacteria

23

Vaccination

•Injecting small amounts of dead or inactive or weakened pathogens which carry antigens which causes your body to produce antibodies to attack them
•So if live pathogens appears after that WBC can rapidly mass produce antibodies to kill the pathogens instead of taking days to learn how to deal with it

24

Pros of vaccination

•Controls lots of communicable diseases that were once common
•Epidemics can be prevented if a large percentage of the population is vaccinated

25

Cons of vaccination

•Don’t always work and give you immunity
•Sometimes have a bad reaction

26

Antibiotic resistant

When a bacteria mutates and is no longer affected by antibiotics
Only non resistant strains of bacteria will be killed
The individual resistant bacteria will survive and reproduce and the population of the resistant strains will increase

27

MRSA

•Superbug is a bacterium resistant to many antibiotics
•Treatment is using an intravenous medication at hospital then specific antibiotics after
•To prevent MRSA isolation, wash hands thoroughly, water or alcohol based hand sanitizer

28

Painkillers

•A medicinal drug used for pain relief
Blocks nerve impulses form the painful part of the body to the brain
•Treat symptoms of disease but do not kill pathogens
•Synthesised to avoid side effects

29

Antibodies

Produced by white blood cells
Each antibody is specific to the pathogen
They stick to the pathogen and clump them together making them easier to remove

30

Antitoxins

Pathogens may produce toxic chemicals
To prevent their effect and make you feel better your white blood cells produce antitoxins

31

MMR

measles mumps and rubella

32

Antibiotic

What is it? A medicine Made from microorganisms that kill off infectious or disease causing microorganisms

33

What do antibiotics do?

Fight off and kill infectious or diseased microorganisms or slow the growth down inhibit bacteria

34

How are antibiotics produced?

Divided from special microorganisms or living systems

35

Where are antibiotics ineffective?

Useless against viral infections as viruses are so simple that they use their host Cecil’s so tou need antiviral drugs l
ONLY WORK ON BACTERIA

36

Drug digitalis

Comes from foxgloves and helps prevent heart disease

37

What makes a good drug ?

Effective
Safe
Stable

38

How are Drug tested?

1. Drugs are tested using computer models and human cells grown in the laboratory
2.drugs that have passes the 1st stage are tested on animals - giving a known amount of the substance to the animals them monitoring them carefully for any side effects
3.drugs that pass animal tests are used in clinical trials - tested on healthy volunteers to check they are safe
Stage 1 : low dose
Stage 2 : increased dose for other trials
Stage 3: increased again

39

Why are drugs not tested on Ill people ?

So there medication doesn’t react bad with the drug
Gives unusable results

40

Placebo (dummy drug)

A fake drug that has no effects on the body ( doesn’t contain any pathogens )

41

What is an open / open label

When they are testing drugs on a patient and the volunteers and doctors know which one they are getting

42

Blind trial

Participants don’t know but doctors know if they are being given the placebo or actual drug

43

Double blind trial

Neither the doctor or the patients know If they are being given the dummy drug or the actual drug

44

What is Thalidomide ?

Is a drug that is now used as a treatment of certain cancers and of a complication of leprosy

45

What was it used to treat in the 1960s?

It was used to treat pregnant women with morning sickness
But it was initially developed as a sleeping pill