Biomass is the mass of living material in one or more organisms.

A pyramid of biomass is a diagram which shows the biological mass (biomass) of organisms at each trophic level in a food chain diagram.

A pyramid of numbers is a diagram which shows the total number of organisms at each trophic level in a food chain diagram.

Pyramids of biomass

Science

Interdependence within ecosystems

Pyramids of number

Plants are adapted for their environment

Animals are adapted for their environment

Ecological sampling of living organisms

Ecological sampling using a quadrat

Conserving biodiversity

Pupils will learn about biotic and abiotic components of an ecosystem, measuring population size, interdependence and competition in ecosystems, how changes in biotic and abiotic factors affect communities, the cycling of carbon and water, and the role of microorganisms in cycling materials through ecosystems.

Pupils learnt about interdependence in ecosystems, covering food webs and food chains along with predator-prey relationships. The effect of the use of pesticides on organisms such as pollinating insects and top predators through bioaccumulation.

This unit examines environmental changes and their impact on species' survival and adaptation, potentially leading to extinction. It also develops skills for interpreting data and observations, evaluating errors, and using SI units and IUPAC chemical nomenclature in scientific contexts.

Biodiversity

the position an organism has within the food chain diagram

What is meant by the term 'trophic level' when we talk about food chain diagrams?

The dry mass of organisms at each trophic level is called ...

pyramids of numbers do not take the size of organisms into account.

it is not easy to count the number of organisms in a population.

the number of organisms in each part of the food chain are always changing.

Pyramids of numbers are not as good as pyramids of biomass because...

The following diagram is a pyramid of biomass.  The population of which organism has the largest biomass?

Look at the food chain diagram and its pyramid of biomass. Put the organisms in the order of biomass (largest first).

What is the biomass of the oak tree in this pyramid of biomass?

Look at the food web diagram below. Which of the organisms is a herbivore?

Look at the food web diagram below. Which of the organisms is a carnivore?

Look at the food web diagram below. Which of the organisms is an omnivore?

Producers make their food from which **two** of the following?

Look at the food chain diagram and match the organism to the correct description.

Look at the pyramid of numbers diagram. How many producers are there in the population?

Starter Quiz

Look at the food web diagram below. Which of the organisms is a herbivore?