B3 And 4

Question 1

Explain 3 types of viral diseases

Answer 1

Measles
• Develop a red rash and a high fever
• Most people are vaccinated

HIV
• Spread by sexual contact, body fluids and needles
• Flu symptoms and attacks immune cells and weakens it

Tobacco mosaic Virus
• Mosaic pattern
• Discolouration- no photosynthesis

Question 2

Explain Fungal disease

Answer 2

Rose black spot
• Black spots on leaves that turn yellow
• No photosynthesis
• Leaves destroyed

Question 3

What type or drugs prevents viruses replicating

Answer 3

Antiretroviral drugs

Question 4

Explain 4 ways in which disease can be prevented

Answer 4

Hygiene
Vaccination
Destroying the vector
Isolating the individual

Question 5

Explain advantages and disadvantages of vaccinations (4 marks)

Answer 5

Help control communicable disease
Stop dangerous pathogens entering the body

Don’t always work
Some people have a bad reaction

Question 6

Name 3 types of drugs from plants

Answer 6

Aspirin
Found in willow
Painkiller

Digitalis
Found in a toxic flower (foxgloves)
Treats heart conditions

Penicillin
Used to kill bacteria