Which one of the following is not a viral disease?

Oxygen is harmful for

Explain the following statement by giving two examples: 'It is not necessary that the pathogen affects an organ or tissue depending upon its point of entry.'

State whether the following statement is true or false:
The diseases which last for only short periods of time are called chronic diseases.

Name two diseases caused by protozoans. What are their causal organisms?

Distinguish between acute and chronic diseases.