B5 Communicable Diseases

Question 1

Pathogen Def-4 types

Answer 1

Microorganism that causes disease : viruses, Bacteria, Fungi, Protists

Question 2

Ways of transmition

Answer 2

Direct contact, Water, Air, Unhygienic food preparation, vectors

Question 3

Direct Contact

Answer 3

This can be sexual contact during intercourse or non-sexual contact, like shaking hands.

Question 4

How can water spread disease

Answer 4

Dirty water can transmit many diseases, such as the cholera bacterium.

Question 5

Spreading disease through Air

Answer 5

Coughing and sneezing spread pathogen particles to others

Question 6

what does Unhygienic food preparation cause

Answer 6

Undercooked or reheated food can cause bacterial diseases like Escherichia coli which is a cause of food poisoning.

Question 7

Vector

Answer 7

Any organism that can spread a disease is called a vector.

Question 8

Viruses GK

Answer 8

Not alive, ‘strains’ not species due to short DNA length surronded by protein coat. Not affected by antibiotics

Question 9

Viruses Life Cycle

Answer 9

• find suitable host
• inject host with DNA
• replicate DNA and protein coats inside
• burst cell to infect more

Question 10

Tobacco mosaic virus

Answer 10

infects tobacco and close species. Trasmitted by contact between plants. Infects chloroplasts, changes colour and reduces its ability to photosynthesis

Question 11

HIV/AIDS

Answer 11

HIV, Spread through body fluids, mild fever. AIDS months - years after infection of HIV. Attacks patient’s immune system

Question 12

Bacterial diseases GK

Answer 12

Not all bad. Do not have a nucleus. much larger than viruses. Treated using antibiotics

Question 13

Gonorrhoea

Answer 13

STD. burning pain when urinating. Thick yellow/green discharge from infected penis/vagina.

Question 14

Salmonella

Answer 14

Causes food poisoning, found in undercooked food. all poultry in UK vaccinated against it to reduce vectors

Question 15

Protist Diseases GK

Answer 15

Mix of plant animal and fungi. eukaroyotic

Question 16

Malaria

Answer 16

Spread by vector (mosquitos). gives fever sweats and chills

Question 17

Fungal diseases GK

Answer 17

not all bad, Not all single celled, eukaroyotic. Can be treated using antifungal medication and fungicides

Question 18

Athlete’s foot

Answer 18

rash caused by fungus. Red dry or white wet skin. Spread in communal areas.

Question 19

Rose black spot

Answer 19

Infects roses, black purple spots on leaves, stop photosynthesis, spreads through air and water

Question 20

How to prevent the spread (6)

Answer 20

Sterilising water-Cholera-Chemicals or UV light kill pathogens in unclean water.

Suitable food hygiene - Salmonella- Cooking foods thoroughly and preparing them in hygienic conditions kills pathogens.

Suitable personal hygiene - Athlete’s foot - Washing surfaces with disinfectants kills pathogens. Treating existing cases of infection kills pathogens.

Vaccination - Measles - Vaccinations introduce a small or weakened version of a pathogen into your body, and the immune system learns how to defend itself.

Contraception - HIV/AIDs - Using barrier contraception, like condoms, stops the transfer of bodily fluids and sexually transmitted diseases.

Question 21

Phagocytes

Answer 21

surround pathogens and engulf them by binding to them. Membrane surrounds them and breaks down from the inside. They are non-specific as they destroy all pathogens

Question 22

Lymphocytes

Answer 22

Recognise proteins on surface of pathogen called antigens. They produce antibodies from them which takes time. These antibodies stick to pathogen and makes it easy for phagocytes to engulf them. They can also produce antitoxins.

Question 23

Skin

Answer 23

Physical barrier. Produce antimicrobial secretions. Microorganisms living on skin prevent growth of pathogens

Question 24

nose

Answer 24

cilia and mucus trap particles in the air, preventing them from entering the lungs. Trachea and bronchi produce mucus which is moved from the lungs to the back of the throat

Question 25

stomach

Answer 25

produces strong acid (hydrochloric pH 2) that destroys pathogens