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The diagram below represents a food web in a certain ecosystem.

(a) Name the trophic level occupied by each of the
following:
(i) Caterpillars.
(ii) Small insects.
(b) From the food web,construct two food chains which end with lizards as a tertiary consumer.
(c) (i) Which organisms have the least biomass in this ecosystem?
(ii) Explain the answer in (c) (i) above.

Answer Text:
(a)(i)- Primary consumer
(ii) Primary consumer/secondary consumer
(b) Green plant #rarr# Caterpillars #rarr# Small insects #rarr# Lizard
Decaying leaves #rarr# Caterpillars #rarr# Small insects #rarr# Lizard
(c) (i) Hawks
(ii) - At each trophic level, energy is lost as heat during respiration and decomposition.
Heat is also lost in defecation/ faeces of metabolis.
Some parts of the body are not eaten, hence less
biomass as one as one moves up the trophic levels.