This question was  attempted by many candidates and their performance was fair.  In part (a) candidates could not correctly  draw and label the diagram as been specified in the question.  In part (b) candidates could not correctly  state function of the parts labelled of a typical animal cell. as seen under a  light microscope.  In part (c) candidates  correctly stated methods by which the spread of malaria can be controlled.  In part (d) candidates wrongly wrote methods  of refuse disposal as methods of preventing water  pollution. 
However, the expected  answers were as follows:       
  
Accuracy  
  NB: Nucleus should be indicated.  Cell should be roughly circular 
 Dimension – not less than 10 lines 
I   -  cell membrane      VI  -    cytoplasm 
II   -   nucleus                 V   -   glycogen granule 
III  -   mitochondrion     VI  -    vacuole 
(b)     Function of the labelled parts
  Function Nucleus 
 
  -  controls activities of cell
 
  -  it allows exchange of materials between the  nucleus and cytoplasm
 
  - development of genetically acquired  traits/hereditary materials                                             
 
 
         Function Vacuole 
  - It acts as a store house for excretory  products                                 
 
 
          Function  mitochondrion 
  - for respiration
 
  - it acts as power house (for energy)                          
 
 
          Function glycogen granule 
  -  stores animal starch/glycogen                           
 
 
           Function cell membrane 
  -  it prevents the cell contents from escaping
 
  -  it controls the materials which are allowed to  enter or leave the cell.
 
 
(c)     Methods  of Controlling malaria 
          -     use drugs to destroy parasite in  humans 
          -     destruction of larvae pouring oil  on stagnant water 
           -    destruction of adult  mosquitoes using insecticide 
          -     live in mosquito proof houses 
          -     introduce fish into water to feed on larvae 
          -     destruction of bleeding places 
          -     destruction of hiding places 
          -      education/public awareness   
                          
  (d)    Methods  of preventing water pollution 
            -     legislation 
           -      treatment of raw sewage before discharge into  water/proper disposal of     
                 sewage 
  - recycling  of industrial waste
 
  - educate  farmers on the correct usage of fertilizers to limit run-off into water bodies
 
  - ban  the use of chemical in fishing
 
  - waste  must be discharged in controlled amount
 
  - oil  leakages must be prevented from tankers
 
  - use  of organic manure other than fertilizers to be encourage
 
  - avoid  thermal pollution/coding of liquid wastes from factories.
 
 
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