Trophic Levels
Biology: AQA GCSE Higher, topic 7.4.1
Food Chains and Trophic Levels
Food chains show feeding relationships and energy flows within a biological community. An organism’s trophic level describes where it fits into a food chain. Trophic levels are given numbers:
Food chain: level 1
- At the base of all food chains, there are green plants and algae.
- These are called producers and use light energy from the Sun to synthesise (make) their own food.
Food chain: level 2
- Herbivores that eat green plants and/or algae are called primary consumers.
Food chain: level 3
- Carnivores that eat herbivores are called secondary consumers.
Food chain: level 4
- Carnivores that eat other carnivores are called tertiary consumers.
- An apex predator is at the highest point in the food chain.
Test yourself on Trophic Levels
Why are producers found at the base of every food chain?
An owl eats a mouse, and the mouse eats grass. Which trophic level number does the owl occupy?
A caterpillar eats a leaf from a plant. What term describes the caterpillar in this food chain?
In a food chain, a snake eats a frog, the frog eats an insect, and the insect eats a plant. What term describes the snake?
A kestrel is the top predator in a food chain, with no animals above it. What term describes the kestrel?