Observation

Many candidates that answered this question could not give the expected answers to the question. Candidates performed well in this question. Spelling errors affected most candidates in their responses to the question.

Some candidates were able to explain ecosystem and state the characteristics of an ecosystem.
Many candidates were not able to state the effect of flood on the ecosystem satisfactorily.
Some candidates could not spell abiotic factors and the instruments for measuring them.

The expected answers are:

(a)  (i)         Ecosystem
Is a biological community; that comprises biotic/living/plant/animal components; and abiotic/non-living/physical components.                                                  

(ii)        Characteristics of an ecosystem

• it is made up of biotic/living/ components/plant/animal;
• and abiotic components/non-living/physical and chemical factors;
• the biotic and abiotic components interact together;
• there is a flow of energy from the sun;
• there is a recycling of nutrients.                                      

            (b)        Effect of flooding on the ecosystem

• there would be soil erosion;
• increase in humidity;
• some terrestrial habitats will be destroyed;
• increase in volume of water in rivers/water bodies;
• availability of water/more water in the ecosystem;
• some terrestrial animals/plants will be destroyed/die;
• establishment of new habitats;
• increased turbidity;
• lowered temperature;
• facilitate growth of vegetation/flora;
• outbreak of diseases/water-borne diseases.                                             

            (c)        Abiotic factors and instruments

                       
Note: Spelling of any four (4) abiotic factors and any four (4) instruments must be correct to score the 8 marks.

            (d)       Habitats in the ecosystem

• aquatic;
• terrestrial;
• arboreal.                                                                                              

Note: Spelling must be correct to score.