problem 1) Classify the following diseases under the headings 'Transmissible' and 'Non-transmissible'.
lung cancer, whooping cough, rickets, arthritis, appendicitis, food poisoning, tuberculosis,   measles, diabetes, anaemia, syphilis, influenza, AIDS, coronary heart disease, haemophilia

problem 2)(a) In droplet infection (i) where do the droplets come from, (ii) what infective agents might they contain?

(b) Give two exs of diseases normally spread by droplets.

problem 3)(a) Give two exs of diseases which can be spread by contaminated drinking water.

(b) How can the spread of such diseases be prevented?

problem 4) Suggest three ways in which food might become contaminated by harmful bacteria.

problem 5) Which one of the following is least important in preventing the contamination of food?

(a) Keeping food away from flies.
(b) Washing the hands before preparing food.
(c) Not coughing or sneezing over food.
(d) Not smoking while preparing food.

problem 6) The following events describe an outbreak of food poisoning in a factory canteen. Put the events in the appropriate order.

(a) Pathogenic bacteria in intestine.
(b) Unwashed hands prepare food.
(c) Kitchen worker has intestinal disease.
(d) Outbreak of food poisoning.
(e) Pathogenic bacteria in faeces.
(f) Pathogenic bacteria get into food.
(g) Hands not washed after defecation.
(h) Faeces expelled in lavatory.
(i) Food ingested by healthy people.

problem 7) Which one of the following is the most appropriate description of a contagious disease?

A contagious disease is one which is spread by

(a) contaminated food,

(b) contaminated drinking water,

(c) contact with an infected person,

(d) droplets from an infected person.

problem 8) In the air passages, a layer of ….. (A) ….. traps bacteria. This ….. (B) …..is carried away from the lings by the action of …..(C) …..cells which line the air passages.

problem 9) The ….. (A) ….. layer of the skin is a barrier to the entry of bacteria. Also the …..(B) ….. glands and ….. (C) ….. glands produce bacteriocidal substances. If bacteria get through damaged skin they are attacked by ….. (D) …..and ….. (E) …..in the blood.

problem 10) What is the purpose of the gauze mask worn by surgeons during an operation?