B5 - Communicable Diseases

Question 1

Pathogen

Answer 1

Microorganism that cause disease

Question 2

Virus

Answer 2

Pathogen much smaller than bacteria that replicates and causes damage from within a cell

Question 3

Microorganism

Answer 3

Usually single celled and can only be seen using a microscope. They include bacteria, fungi, viruses and protists.

Question 4

Aphids

Answer 4

Insects that penetrate plants phloem and feed on dissolved food

Question 5

Measles

Answer 5

• virus
• red skin rash
• children vaccinated against it
• spreads through droplets in sneezes and coughs

Question 6

HIV

Answer 6

• sexually transmitted or through exchange of bodily fluid
• can be controlled with antiretroviral drugs
• attacks body’s immune system
• latter stages (AIDS) body can no longer defend itself from diseases

Question 7

Salmonella

Answer 7

• bacteria
• spread through raw or unsanitary food
• poultry vaccinated against it
• fever, abdominal cramps, vomiting and diarrhoea

Question 8

Gonorrhoea

Answer 8

• bacteria
• thick green/yellow discharge
• controlled by penicillin but now there are too many resistive strains
• prevented through barrier methods and treated with antibiotics

Question 9

Tobacco Mosaic Virus

Answer 9

• pattern of discolouration on leaves
• lack of photosynthesis so stunted growth

Question 10

Rose Black Spot

Answer 10

• fungi
• black or purple spots on leaves which often turn yellow and the drop
• affects growth
• spread by water or wind
• treated by removing infected leaves and fungicides

Question 11

Malaria

Answer 11

• disease spread by protist mosquito
• recurrent fever
• use mosquito nets

Question 12

what is a communicable disease

Answer 12

a disease that can be transmitted from one organism to another

Question 13

how do pathogens spread

Answer 13

air, water, direct contact

Question 14

four methods of controlling spread of communicable disease

Answer 14

good hygiene, isolating infected individuals, controlling vectors, vaccination

Question 15

how can cause of plant disease be identified

Answer 15

gardening manuals and websites, laboratory testing, monoclonal antibody kits

Question 16

three mechanical defences that protect plants

Answer 16

thorns and hairs, leaves that droop or curl, mimicry to trick animals

Question 17

three physical defences of plants

Answer 17

cellulose cell walls, tough waxy cuticles, bark on trees

Question 18

how can aphids be controlled by gardeners

Answer 18

introduce lady birds to eat aphids

Question 19

how can plant diseases be detected

Answer 19

• areas of decay
• discolouration
• growths
• malformed stems or leaves
• presence of pests
• spots on leaves
• stunted growth