Food Pyramids Flashcards

All 5 cards in this deck

What is a pyramid of biomass?

A diagram of horizontal bars showing the total dry mass of organisms at each trophic level, drawn to scale.

What are the steps to draw a pyramid of biomass to scale?
e.g. grass $4000$ kg, rabbits $400$ kg, foxes $40$ kg

1. Choose a scale that fits the largest value: $1$ cm $= 1000$ kg.
2. Draw bars of that width, producer at the bottom: $4$ cm, $0.4$ cm, $0.04$ cm.
3. Label each bar with the organism's name.

In a pyramid of biomass, which trophic level is drawn at the bottom?

The producer, and it has the widest bar.

Why is a pyramid of biomass almost always pyramid-shaped?

Biomass decreases at each trophic level because energy and material are lost between levels.

True or false? The bars of a pyramid of biomass can be drawn any length as long as they get smaller going up.

False. The bars must be drawn to scale, in proportion to the biomass values given.