IGCSE Biology 19.1 Energy flow Topic Practice

The dominant grass species in an African grassland ecosystem are star grass and red oat grass.
- Star grass is eaten by antelope species, such as topi and Thomson's gazelle.
- Smaller animals such as mice and grasshoppers feed on red oat grass.
- Topi and Thomson's gazelle are eaten by predators such as cheetahs, lions and serval cats.
- Grasshoppers and mice are eaten by serval cats and tawny eagles.
- Vultures feed on dead mammals.

Fig. 1.1 shows part of the food web for this ecosystem.

Fig. 1.1 shows a pyramid of biomass and part of the carbon cycle.

State the principal source of energy required for trophic level D of the pyramid of biomass in Fig. 1.1.

The dominant grass species in an African grassland ecosystem are star grass and red oat grass.
- Star grass is eaten by antelope species, such as topi and Thomson's gazelle.
- Smaller animals such as mice and grasshoppers feed on red oat grass.
- Topi and Thomson's gazelle are eaten by predators such as cheetahs, lions and serval cats.
- Grasshoppers and mice are eaten by serval cats and tawny eagles.
- Vultures feed on dead mammals.

Fig. 1.1 shows part of the food web for this ecosystem.

Outline how organisms in the first trophic level of the woodland food chain produce biomass using energy from the Sun.

Phytoplankton are microorganisms that photosynthesise.

A scientist made notes about a marine food web.

Fig. 5.1 shows the notes she made.
- In the sea, phytoplankton photosynthesise.
- Phytoplankton are eaten by small organisms in the sea, called zooplankton.
- Herring fish and cod fish eat phytoplankton. Herring fish also eat zooplankton.
- Cod fish eat other fish such as herring.

State the principal source of energy for this food web.

The diagram shows energy flow through an ecosystem.

In what form is energy transferred at X ?

What is the principal source of energy input into an ecosystem?

Where does the energy being transferred along a food chain originally come from?

Energy flows through a food chain.
In which form does the energy first enter the food chain?

The diagram shows the flow of energy through living organisms.

Which term should be placed in both boxes to complete the diagram?