Observation

This question was compulsory.
Question (a) was well answered as most candidates could state some processes involved in the water cycle.
In (b), Some candidates could name the instrument used for measuring each of the listed physical factors but poor spellings made them lose marks.
In (c), some candidates performed well in this question although some were stating the cell theory.
In (d), some candidates could partially define the terms.
In (e), many candidates got the drawing of the human tongue but could not locate the specific areas of taste on the tongue.
In (f), many candidates could answer this question correctly.

The expected answers are:
(a) Processes involved in water cycle

• Respiration by plants/animals;
• Transpiration;
• Surface run-off/erosion;
• Excretion by plants/animals;
• Decay of plants/animals;
• Precipitation /rainfall;
• Condensation of water vapour/ cloud;
• Absorption of water by root hairs;
• Evaporation;
• Percolation;
• Perspiration/ sweating;                                                                       

Spelling of terms must be correct to score.                                                

(b) Instruments for measuring the following physical factors
pH  – pH meter/pH paper/ colorimeter;
Light intensity – light meter/photometer;
Turbidity   – Secchi disc;
Temperature  –thermometer.                                                                                   

(c) Contributions to cell theory
(i) Robert Hooke: He discovered the cell; while using a microscope to examine the cork from a tree bark; he observed honeycomb structures/dead cell walls surrounding empty holes; which he called ‘cells’.                                                                         
(ii) Theodore Schwann: Examined bits of different animals under the microscope; and observed that all animals are composed of cells.                                                           
(d) (i) Nastism
Refers to the non-directional response of plant organs/part of a fixed plant to external /non-directional or diffused stimuli/touch/temperature/humidity/( e.g. leaves of Mimosa plant folding up when touched); it is not a growth movement; it is reversible (e.g. 4-0-clock flower).                                                                                                 
(ii) Taxism

It is not a growth movement; directional response of motile/whole organisms; towards / away from to an external stimulus/ light/ chemicals/ temperature; (e.g. Euglena swimming away from chemicals; Euglena swimming towards light, etc.) 

(e) Diagram of the human tongue showing areas of taste

Title (TL): Human tongue showing areas of taste                 
Size (Sz): 6cm – 8 cm long                                                    
Correct location of taste (CL)                                                
Labels (L)                                                                               
                                                                                                                       
(f) (i) Ways through which microbes enter the human body

• Through some parts of the body/Mouth; mucous membranes/mucosa; anus; skin; birth canal /vagina; nose;
• Insect bite;
• Blood contact;
• Direct contact with infected person/animal;
• Body secretions/semen/saliva/sweat/vaginal fluids/tears/mucus;
• Food;
• Water;
• Inhalation/aerosol.                                                                              

Note:  Spellings must be correct to score.

     (ii) Harmful effects of microbes to humans

• Causes various diseases in humans;
• Involved in spoilage of food;
• Causes death of humans;
• Destruction of materials/wood/cotton/leather/paper/any correctly named example.