QUESTION 1
(a) Describe what is meant by the following terms-
(i) Community
(ii) Ecosystem
(iii) Habitat
(iv) Population
(b) Industrialisation and population growth have had a negative impact on the natural environment resulting in pollution. Elaborate on the different types of pollution and discuss some of the measures that can be taken to mitigate their effects
(c) Describe the Nitrogen Cycle with emphasis on the role of microorganisms
QUESTION 2
"It is believed that eukaryotic cells have evolved from prokaryotic cells." Discuss this statement with reference to the differences between these two types of cells
QUESTION 3
(a) Using a labelled diagram show the different parts of the human respiratory system and describe the mechanism of breathing
(b) The human respiratory system is susceptible to a number of diseases. List and describe the causes and symptoms of five such diseases
QUESTION 4
(a) Draw a labelled diagram of a motor neurone
(b) Describe the sequence of events which takes place during transmission of an action potential and describe how information is transmitted across a cholinergic synapse
(c) Briefly describe one example of a reflex arc