Ecosystems (OCR GCSE Biology A (Gateway)): Exam Questions

Exam code: J247

3 hours37 questions
1
Sme Calculator
1 mark

The diagram below shows a food chain

grass → locusts → snakes → eagles

If the number of snakes decreases due to disease, what will happen to the numbers of the other organisms in the food chain?

 

grass

locusts

eagles

A

increase

increase

increase

B

increase

decrease

increase

C

decrease

decrease

decrease

D

decrease

increase

decrease

    2
    Sme Calculator
    1 mark

    Which of the following factors does NOT affect the rate of decomposition of biological material within an ecosystem?

    • Availability of oxygen

    • Presence of predators nearby

    • Temperature

    • Availability of water

    3
    Sme Calculator
    1 mark

    The diagram below illustrates part of the carbon cycle.

    image-1

    Which process is shown by the arrow labelled Y?

    • Photosynthesis

    • Feeding

    • Respiration

    • Combustion

    4
    Sme Calculator
    1 mark

    Which of the following options shows four ecological terms in a logical order, starting with the smallest and ending with the largest?

    • individual → community → population → ecosystem

    • population → individual → ecosystem → community

    • community → population → ecosystem → individual

    • individual → population → community → ecosystem

    5
    Sme Calculator
    1 mark

    Which of the following diagrams shows a pyramid of biomass for a marine ecosystem?

    image-9
      6
      Sme Calculator
      1 mark

      There are different levels of organisation within an ecosystem.

      What is the correct order of these levels?

      • individual, community, population, ecosystem

      • community, individual, ecosystem, population

      • individual, population, community, ecosystem

      • population, community, ecosystem, individual

      7
      Sme Calculator
      1 mark

      Look at the information about a food chain.

      Organism

      Number

      Biomass

      Oak tree

      1

      500,000

      Aphids

      10,000

      1,000

      Ladybirds

      200

      50

      Calculate the percentage biomass of the aphids transferred to the ladybirds.

      • 0.05%

      • 20%

      • 5%

      • 2000%

      8
      Sme Calculator
      1 mark

      The diagram shows a food web.

      q3-paper2f-spec2018-ocrgcsebio

      What is the most likely effect on the food web, if the number of cod decreases?

      • An increase in the number of herrings

      • An increase in the number of krill

      • An increase in the number of sharks

      • No effect on the population of puffins

      9
      Sme Calculator
      1 mark

      Look at the pyramid of biomass.

      q4-paper2f-spec2018-ocrgcsebio

      What can you tell from this pyramid of biomass?

      • All four trophic levels contain consumers.

      • Fleas are producers.

      • The trophic level with oak trees has the lowest biomass.

      • There are fewer birds than caterpillars.

      10
      Sme Calculator
      1 mark

      Organisms in an ecosystem are affected by biotic factors.

      Which term is a biotic factor?

      • Disease

      • Light intensity

      • Rainfall

      • Wind speed

      11
      Sme Calculator
      1 mark

      In food chains, biomass is lost between different trophic levels.

      One reason for this is the release of undigested food from the body.

      Which term is used to describe this release?

      • Decomposition

      • Egestion

      • Excretion

      • Peristalsis

      12
      Sme Calculator
      1 mark

      Which of these is an abiotic factor that can affect organisms?

      • Food availability

      • Light intensity

      • Pathogens

      • Predators

      13
      Sme Calculator
      1 mark

      The diagram shows the water cycle.

      q2-paper2f-june2019-ocrgcsebio

      Which label, A, B, C or D, represents evaporation?

        14
        Sme Calculator
        1 mark

        Which relationship describes an organism living on an animal and harming it?

        • Decomposition

        • Mutualism

        • Parasitism

        • Predation

        15
        Sme Calculator
        1 mark

        Most food chains only have a maximum of five trophic levels. Explain why.

        • Organisms always get larger at higher trophic levels.

        • Energy is lost at each trophic level.

        • It is more energy efficient to eat meat than plant material.

        • The number of organisms feeding always increases at higher trophic levels.

        16
        Sme Calculator
        1 mark

        Which process in the carbon cycle takes in carbon dioxide from the air?

        • Combustion

        • Decomposition

        • Photosynthesis

        • Respiration

        17
        Sme Calculator
        1 mark

        The diagram shows a pyramid of biomass.

        q2-paper2f-june2018-ocrgcsebio

        Which trophic level is X?

        • Primary consumers

        • Producers

        • Secondary consumers

        • Tertiary consumers

        18
        Sme Calculator
        1 mark

        Which is the correct definition of a parasite?

        • An organism that is always at the top of a food chain.

        • An organism that kills and eats another organism.

        • An organism that lives on another living organism so that they both benefit.

        • An organism that lives on or in another living organism causing it harm.

        19
        Sme Calculator
        1 mark

        The diagram shows a food web in the sea.

        q4-paper2h-nov2020-ocrgcsebio

        The number of penguins decreased in the area. This caused an increase in seal numbers.

        What is a possible reason for the increase in seal numbers?

        • Fewer seals were eaten.

        • The krill numbers dropped.

        • There were more plankton for the seals to eat.

        • The seals had less competition for squid.

        20
        Sme Calculator
        1 mark

        The diagram shows pyramids of biomass for two food webs, X and Y.

        q14-paper2h-nov2020-ocrgcsebio

        Which statement explains the difference between the two pyramids?

        • In food web X there is a greater efficiency of transfer between primary consumer and secondary consumer than in Y.

        • In food web X there is a greater efficiency of transfer between secondary consumer and tertiary consumer than in Y.

        • In food web X there is a lower efficiency of transfer between primary consumer and secondary consumer than in Y.

        • In food web X there is a lower efficiency of transfer between secondary consumer and tertiary consumer than in Y.

        21
        Sme Calculator
        1 mark

        The diagram shows part of a cycle in an ecosystem.

        q1-paper2f-nov2020-ocrgcsebio

        What is the name of the cycle shown in the diagram?

        • Carbon cycle

        • Hydrogen cycle

        • Nitrogen cycle

        • Sulfur cycle

        22
        Sme Calculator
        1 mark

        Goldfish are a species of fish. What name is given to all the goldfish living in a pond?

        • A community

        • An ecosystem

        • A habitat

        • A population

        23
        Sme Calculator
        1 mark

        This is a food chain for organisms in a forest.

        Oak tree ⟶ Greenfly ⟶ Ladybird ⟶ Blackbird

        Which is the correct shape for a pyramid of biomass for this food chain?

        q4-paper2f-nov2020-ocrgcsebio