Energy flow

The diagram illustrates the energy contained in a food chain: $40\,000\ \text{kJ}$ photosynthesising phytoplankton $\rightarrow$ $4000\ \text{kJ}$ krill $\rightarrow$ $400\ \text{kJ}$ herring $\rightarrow$ $40\ \text{kJ}$ bass. What percentage of the energy in the producer is passed on to the secondary consumer?

Feb/March 2017

Which diagram illustrates the way energy moves through an ecosystem?

Feb/March 2018

The diagram illustrates energy transfer within an ecosystem. In which form is energy passed on at X?

Feb/March 2018

What is the main source of energy entering biological systems?

Feb/March 2019

What is the main energy source for living things?

Feb/March 2020

Which row shows the way energy passes through a biological system?

Feb/March 2020

What is the main source of energy that enters food chains?

Feb/March 2021

The figures in the diagram indicate the amount of energy transferred through part of an ecosystem. How much energy is transferred from herbivores to carnivores?

Feb/March 2023

The diagram illustrates a food chain. phytoplankton → zooplankton → herring → sea lion Which diagram represents a pyramid of energy for this food chain?

Feb/March 2023

Explain how phytoplankton reduce carbon dioxide concentrations in the atmosphere.

Feb/March 2024

A coral reef includes species such as stony corals, sponges, seahorses and whale sharks. These species interact with one another and are influenced by the water temperature, salt concentration and oxygen concentration. Using all the information provided, what is being described?

Feb/March 2025

Black truffle is a fungus that gains nutrients from the roots of hazel trees. Female pigs locate and consume the fungi. What is the main source of energy in this food chain?

May/June 2018

Which energy source is the main one for most food chains?

May/June 2018

The diagram represents a food chain. maize $\rightarrow$ locusts $\rightarrow$ lizards $\rightarrow$ snakes $10000\,\text{kJ}$\quad $1000\,\text{kJ}$\quad $100\,\text{kJ}$\quad $10\,\text{kJ}$ Calculate the efficiency of energy transfer between the maize and the lizards in this food chain?

May/June 2018

Which trophic level contains the largest amount of energy?

May/June 2019

The diagram illustrates the energy present in the producers in an ecosystem, how much is passed to primary consumers, and how much is eventually lost to the environment. How much energy is passed from primary consumers to secondary consumers?

May/June 2019

The diagram illustrates the transfer of energy. Sun $\rightarrow$ grass $\rightarrow$ rabbit $\rightarrow$ fox Which form of energy is transferred at points 1 and 3 on the diagram?

May/June 2021

The diagram illustrates energy transfer along a food chain. The arrows that are labelled indicate the energy transfers. Which energy transfers are indicated by the labelled arrows?

May/June 2021

The diagram illustrates energy moving from the Sun, via a food chain, and then into the environment. What form of energy does each numbered arrow represent?

May/June 2023

From where does the energy transferred through a food chain first come?

May/June 2023

The diagram illustrates energy transfer from the Sun, through a food chain and into the environment. What form of energy does each numbered arrow represent?

May/June 2023

From what original source does the energy transferred along a food chain come?

May/June 2023

In a forest, which diagram depicts a pyramid of biomass?

May/June 2023

What is the principal source of energy entering biological systems?

May/June 2024

What is the main source of energy entering an ecosystem?

May/June 2024

What is the main energy source for biological systems?

May/June 2025

Which is the main source of energy entering biological systems?

May/June 2025

Which statement is correct about a pyramid of energy for a food chain?

May/June 2025

Which row shows the direction of energy transfer into and along a food chain that begins with a plant?

May/June 2025

The diagram illustrates the transfer of energy, measured in energy units, through a food chain. Producers: 1000 units → primary consumers: 100 units → secondary consumers: 10 units → tertiary consumers: 1 unit. What percentage of energy is lost between the producers and secondary consumers?

May/June 2025

Fig. 1.1 is a pyramid of energy for an ecosystem. The diagram gives energy values in joules (J): Trophic level 1: 11 212 J Trophic level 2: 9804 J Trophic level 3: 822 J Trophic level 4: 98 J The labels on the diagram are energy / J, trophic level, and trophic levels 1 to 4 are shown as stacked bars.

May/June 2025

What is the main source of energy entering a food chain?

Oct/Nov 2016

The diagram illustrates the transfer of energy through an ecosystem. What does X stand for?

Oct/Nov 2016

The diagram illustrates a food chain. How much energy is passed to the bird?

Oct/Nov 2016

Fig. 10.1 illustrates the movement of energy through a simple food chain. For every 200 J of energy in the cabbage eaten by the caterpillar, 35 J is transferred to the bird. In the diagram, a cabbage has an arrow marked 200 J pointing to a caterpillar. From the caterpillar, an arrow marked 35 J points to a bird. From the caterpillar, an upward arrow is labelled "lost in faeces 100 J" and a downward arrow is labelled "3 J lost in respiration".

Oct/Nov 2016

A food chain is illustrated. potato plant $\rightarrow$ slug $\rightarrow$ hedgehog Through which process is energy passed from the potato plant to the slug?

Oct/Nov 2017

Yeast is capable of respiring both aerobically and anaerobically.

Oct/Nov 2017

Which diagram shows the correct flow of energy?

Oct/Nov 2019

Which row shows how energy enters and passes through a food chain beginning with a plant?

Oct/Nov 2019

In what ways do green plants and mammals obtain their energy?

Oct/Nov 2019

Which source provides the first energy input to most biological systems?

Oct/Nov 2021

The diagram illustrates how energy moves through living organisms. Energy from the Sun → photosynthesis → [box] → energy in plants → feeding → [box] → energy in animals. Which term should be written in both boxes to finish the diagram?

Oct/Nov 2022

The diagram illustrates how energy passes through a food chain. Which row gives the correct labels for this energy-flow diagram?

Oct/Nov 2022

It is estimated that $90\%$ of the energy passing through living organisms in a food chain is lost from one trophic level to the next. The producers in a food chain have $1000$ units of energy. How many units of energy will reach the quaternary consumers in the food chain?

Oct/Nov 2023

The diagram represents a food chain: tree $\rightarrow$ insect $\rightarrow$ blue tit $\rightarrow$ hawk. Which statement about a pyramid constructed from this food chain is correct?

Oct/Nov 2023

The energy transfers in an ecosystem are shown below. Which of these transfers are correct?

Oct/Nov 2024

Which diagram shows the energy flow correctly?

Oct/Nov 2024

The diagram indicates the quantity of energy, in $\text{kJ m}^{-2} \text{yr}^{-1}$, at each trophic level in a food chain. Producers $88000 \rightarrow$ primary consumers $14000 \rightarrow$ secondary consumers $2000$. Approximately how much energy is lost from the producers to the secondary consumers?

Oct/Nov 2024

The diagram illustrates an ecological pyramid. Which letter indicates the producers?

Oct/Nov 2025

The diagram illustrates the energy contained in the producers in an ecosystem and the amount passed on to primary consumers before being lost to the environment. How much energy is transferred from primary consumers to secondary consumers?

Oct/Nov 2025

Black truffle is a fungus that takes nutrients from the roots of hazel trees. Deer locate and consume the fungi. What is the energy source for this food chain?

Oct/Nov 2025

The diagram illustrates a simple food chain. green plants → chickens → foxes. Energy loss is shown at points 1, 2 and 3. Which process releases the energy that is lost at 1, 2 and 3?

Oct/Nov 2025

The diagram depicts an ecological pyramid. At which levels in the diagram are carnivores found?

Oct/Nov 2025

Which flowchart illustrates the transfer of energy from the Sun to an organism?

Oct/Nov 2025

What unit could be used for the measurements required to construct an energy pyramid?

Oct/Nov 2025

At which trophic level are herbivores located?

Oct/Nov 2025

Steppe ecosystems are broad grassland regions in central Asia.

Oct/Nov 2025