Energy flow in food webs

What you’ll learn about energy flow

Energy flow in food webs explains who eats whom, how much energy is passed on, and why ecosystems can only support so many trophic levels. You’ll practice interpreting feeding relationships, energy pyramids, and the roles of producers, consumers, and decomposers.

Expect questions that connect concepts like productivity, biomass, and ecological efficiency to real food web scenarios. You’ll also see how changes to one population can ripple through a web.

Quiz format and difficulty settings

Each question has 4 options and there’s no timer, so you can think through each step of the pathway. You can choose the question count and the difficulty before you start - short sets for quick revision or longer runs to build stamina.

Difficulty is mixed on purpose: easier items cover core definitions (trophic level, apex predator), while harder ones test application (predicting outcomes after a species is removed). This balance helps you warm up, then stretch your understanding.

Common pitfalls to avoid

• Mixing up energy flow (one-way) with nutrient cycling (reused)
• Confusing food chains (linear) with food webs (interconnected)
• Assuming "10% rule" is exact in every ecosystem and situation
• Forgetting decomposers/detritivores and their role in energy pathways
• Misreading arrows in food webs (they point from food to consumer)

Tips to score higher

Slow down on diagram questions and identify producers first, then trace arrows upward to higher trophic levels. When stuck, eliminate options that violate basic constraints (energy decreases at each transfer; top predators are fewer and require large energy input).