INFECTION AND RESPONSE - Viral Diseases

Question 1

Viruses

Answer 1

Reproduce rapidly in body cells causing damage to the cells

Question 2

Measles

Answer 2

Symptoms is fever and red skin rash. Can be spread by breathing in droplets from sneezing and coughs. It can be fatal if there are complications so young children are vaccinated against measles

Question 3

HIV

Answer 3

Spread by sexual contact or exchange of bodily fluids e.g transmitted in blood by drug users using needles. First HIV causes flu-like illness. If untreated virus enters the lymph nodes and attacks the bodys immune cells. Late stage is when bodys immune system is damaged and cannot fight off other infectious diseases. Taking antiviral drugs can delay its happening.

Question 4

Tobacco Mosaic Virus (TMV)

Answer 4

Plant pathogen affecting many species of plants including tomatoes. It gives a distinctive ‘mosaic’ pattern of discolouration reducing chlorophyll content of leaves. Therefore affects photosynthesis and plant growth.