Food webs and trophic levels: WAEC Biology Past Questions and Answers

What the WAEC syllabus covers in Food webs and trophic levels

Our summary: Producers, consumers and decomposers, food chains and webs, energy pyramids and decomposition.

• Autotrophs and heterotrophs: producers: autotrophs; consumers: heterotrophs; decomposers (Candidates should be able to classify organisms as producers, consumers and decomposers. Aquatic and terrestrial producers, consumers and decomposers should be known.)
• Trophic levels energy relationships: food chain; food web (Candidates should illustrate food relationships in a food chain and food web using specific examples.)
• Energy flow: food/energy relationship in aquatic and terrestrial environment
• Pyramid of energy and pyramid of numbers (Non-cyclic nature of energy transfer should be mentioned. Candidates should be able to construct and explain pyramid of energy, pyramid of numbers and point out the major differences between them.)
• Decomposition in nature: decomposers (micro and macro-decomposers); gaseous products; role of decomposers (Candidates should observe demonstrations to show that carbon dioxide, hydrogen sulphide, heat energy are released during decomposition.)

Syllabus content © The West African Examinations Council (WASSCE (harmonised West African syllabus)).