This question was attempted by many candidates and their performance was good. In part (a)(i) many candidates correctly stated reasons for drug addiction, a few of the candidates listed self medication , misinformation, poverty and cultural deprivation as reasons for drug addiction and in (a) (ii) candidates could not correctly highlight preventive measures for drug addiction. In part (b) many candidates correctly stated functions of the structures of the respiratory parts such as trachea, lungs, nose and ribs. In part (c) many candidates correctly mentioned substances involved in the exchange of gases during breathing.
The expected answers are as follows:
4(a) Reasons for drug addiction
- Curiosity/passion/desire to test or experiment
- lack of self confidence
- peer group pressurebr
- illiteracy
- searching for excitement/to feel high
- to escape the challenges of life
- to reduce stress and frustration
- to challenge people in position of authority/boldness
- to keep awake
- environmental/occupational/influence
- lack of parental care/and guidance.
(ii) Preventive measures for drug addiction
- mass education/counselling
- keeping drugs away from youth/avoid environment or groups where drugs are used
- employment/empowerment programme
- strict adherence to doctor’s instruction on the use of drugs
- severe punishment of drug addicts by government
- provision of recreational centres for youth and adult
- law against drug addicts
- banning importation/production of hard drugs
- keeping good friends/avoiding bad friends.
(b) Functions of the following structures of the respiratory system
(i) Functions of trachea
- for passage of air down to the lungs
- the cilia filters and expel dust or foreign particles
going into the lungs
- it humidifies the air/warms the air
(ii) Functions of lungs
- exchange of gases
- absorption of oxygen
- It provides large surface area for exchange of gases
- expulsion of carbon dioxide
(iii) Functions of nose
- removes impurities and dust
- moistens/humidifies the air
- warms the air
- passage for air/inhalation and exhalation/breathing.
(iv) Functions of ribs
- aids respiration by moving up and down
- contraction of intercostal muscles/alter the volume of chest/thoracic
cavity
- protects the respiratory organs.
- protecs the heart.
(c) Substances involved in the exchange of gases during breathing
- Oxygen
- Carbon dioxide
- Water vapour |