Infection and response - Communicable diseases

Question 1

what are pathogens

Answer 1

microorganisms that enter the body and cause disease

Question 2

what are bacteria

Answer 2

very small cells which can reproduce rapidly inside your body

Question 3

how do bacteria make you ill

Answer 3

• they make you feel ill by producing toxins toxins that damage your tissues

Question 4

what are viruses

Answer 4

non - living particles which can reproduce rapidly inside your body

Question 5

how do viruses make you ill

Answer 5

• they invade a host cell
• they then reproduce inside the host cell
• when the virus leaves the cell, it can cause the cell to burst open and die

Question 6

what are protists

Answer 6

single celled eukaryotes which make us feel ill by damaging tissues

Question 7

what are fungi

Answer 7

single celled organisms that have a body made of hyphae

Question 8

how does hyphae make you ill

Answer 8

can grow and penetrate human skin and the surface of plants, causing disease

• can also produce spores, which can be spread to other plants and animals

Question 9

name the 3 ways pathogens can be spread

Answer 9

• air
• water
• direct contact

Question 10

describe how pathogens can be spread through water

Answer 10

• pathogens can be picked up by drinking or bathing in dirty water - e.g - cholera is a bacterial infection caused by drinking dirty water

Question 11

describe how pathogens can be spread through air

Answer 11

• pathogens can be carried by the air and breathed in
• some are carried in droplets produced when you cough or sneeze - e.g - influenza virus

Question 12

describe how pathogens can be spread through direct contact

Answer 12

• pathogens can be picked up by touching contaminated surfaces - e.g athletes foot

Question 13

what are the three viral diseases I need to know

Answer 13

measles, HIV, tobacco mosaic virus

Question 14

Measles, what it is, how its spread ,symptoms and preventions

Answer 14

• it’s a viral disease spread by droplets from an infected persons sneeze or cough
• symptoms include red skin rash, fever
• can be very serious, can lead to pneumonia or inflammation of the brain
• most people are vaccinated against measles when they’re young to prevent it

Question 15

HIV , what it is, how it’s spread, symptoms and preventions

Answer 15

• its a virus spread by sexual contact or by exchanging bodily fluids such as blood ( sharing needles )
• causes flu like symptoms for a few weeks, they then don’t experience any other symptoms for a few years, during this time, HIV can be controlled with antiretroviral drugs
• this virus attacks the immune cells, if it’s too damaged . it can’t deal with other infections or cancers, at this stage, the virus is known as aids

Question 16

Tobacco mosaic virus causes diseases etc

Answer 16

• its a virus that affects many species of plant
• mostly tomato plants
• causes a mosaic pattern on the leaves of the plant and causes the leaves to become discoloured
• meaning the rate of photosynthesis is reduced, so the plants growth is reduced

Question 17

what is rose black spot

Answer 17

• fungal disease that causes purple or black spots on the leaves of rose plants, this makes the leaves turn yellow and drop off
• this means less photosynthesis , which means the plant doesnt grow very well
• fungus spreads by water or wind
• can be treated by using fungicides or cutting off and destroying affected leaves so fungus doesn’t spread to other rose plants

Question 18

malaria, how its spread etc

Answer 18

• caused by protists
• mosquitoes ( vectors ) pick up the protist and gives it to whatever animal it feeds on by inserting it into the animals blood vessels
• causes fever, headaches, muscle aches,can be fatal
• can be stopped by stopping mosquitoes from breeding or using insecticides and mosquito nets

Question 19

what bacterial diseases do I need to know

Answer 19

gonorrhoea and salmonella

Question 20

gonorrhoea, how its spread etc

Answer 20

• sexually transmitted disease
• caused by bacteria
• pain when urinating, yellow or green discharge
• prevented by using protection or using antibiotics
• also prevented if you get tested for gonorrhoea after having unprotected sex

Question 21

why is it harder to treat gonorrhoea with antibiotics

Answer 21

some strains of bacteria have become resistant to it

Question 22

salmonella, how its spread etc

Answer 22

• type of bacteria which causes food poisoning
• symptoms include vomiting, diarrhoea, fever, stomach cramps
• caught by eating food which has been contaminated with salmonella bacteria like eating raw chicken or chicken that had been contaminated by being prepared in unhygienic conditions
• in the UK, poultry is vaccinated against salmonella

Question 23

how can basic hygiene reduce/ prevent the spread of disease

Answer 23

for example, washing your hands after you sneeze gets rid of bacteria, stopping you from infecting another person

Question 24

how can destroying vectors reduce / prevent the spread of disease

Answer 24

prevents the disease from being passed on as they cannot breed

Question 25

how can isolation reduce / prevent the spread of diseases

Answer 25

isolating someone with a communicable disease prevents them from passing it to anyone else

Question 26

how does vaccination prevent the spread of diseases

Answer 26

makes you never get the disease

Question 27

what is the vector for malaria

Answer 27

female anopheles mosquito

Question 28

what is the difference between viruses and bacteria

Answer 28

viruses cannot reproduce by themselves, they can only reproduce inside a host cell

Question 29

ways to reduce the spread of pathogens

Answer 29

• drink clean water
• practising basic hygiene like washing hands
• using protection
• isolation
• vaccination

Question 30

how are viral diseases treated

Answer 30

using antiretroviral drugs, to stop the virus from multiplying inside the patient, so it doesn’t damage the patients immune system

Question 31

disadvantages of antiretroviral drugs

Answer 31

• they are not a cure for HIV
• must be taken for the rest of patients life

Question 32

describe the life cycle of the malaria vector

Answer 32

1. infected person is bitten by a mosquito
2. The malaria pathogen passes into the mosqito
3. mosquito then bites another person and gives them the disease

Question 33

how to reduce the spread of malaria

Answer 33

• spray areas of still water with insecticide, so that they cant breed
• drain areas of still water
• use a mosquito net when sleeping