Energy flow — Paper 2 · IGCSE Science - Combined 0653

12 Energy flows along a food chain. What does every food chain start with? A carnivore B consumer C herbivore D producer

1 marks

Answer: D

This question in 0653/22 Feb/March 2017

12 What is an ecosystem? A a network of inter-connected food chains B a specific area in which a plant or an animal lives C all the plants and animals living within a specific area D the interactions between all living organisms, in a specific area, and their environment

1 marks

Answer: D

This question in 0653/22 May/June 2017

12 The diagram shows a food web. hawk song bird spider locust beetle tree grass Which statement about this food web is correct? A Some of the energy from the grass eventually passes to the hawk. B The producers get their energy from the soil. C There are more carnivores shown than herbivores. D There are six consumers shown.

1 marks

Answer: A

This question in 0653/22 Oct/Nov 2017

12 The diagram shows the trophic levels of a food chain. producer herbivore carnivore carnivore → → → 1st trophic 2nd trophic 3rd trophic 4th trophic level level level level Why do most food chains not have more than four trophic levels? A There are too many carnivores in the 3rd trophic level. B There are too many herbivores in the 2nd trophic level. C There is no energy transferred from the 2nd trophic level to the 3rd trophic level. D There is not enough energy available to be transferred to a 5th trophic level.

1 marks

Answer: D

This question in 0653/23 Oct/Nov 2017

11 In a food chain, the energy transferred from the first trophic level to the second trophic level is greater than the energy transferred from the second trophic level to the third trophic level. Which process is not a reason for this difference? A egestion B excretion C movement D photosynthesis

1 marks

Answer: D

This question in 0653/22 May/June 2018

13 The diagram shows how energy flows through a food chain. Sun Y Y Y X Z Z producer herbivore carnivore What are the main energy transfers shown by arrows X, Y and Z? X Y Z A chemical → chemical chemical → heat chemical → light B chemical → chemical chemical → light chemical → light C light → chemical chemical → heat chemical → chemical D light → chemical chemical → light chemical → chemical

1 marks

Answer: C

This question in 0653/23 May/June 2018

11 The graph shows the energy content of organisms at each trophic level in a food chain. Which letter represents the primary consumers? 1000 100 energy / arbitrary 10 units 1 0 A B C D

1 marks

Answer: C

This question in 0653/22 Feb/March 2019

12 A farmer chops down a tree to provide firewood. He gets warm when chopping down the tree. The farmer then burns the wood to keep warm. What is the original source of the energy that warms the farmer in both cases? A photosynthesis by the tree growing the wood B respiration C the match used to light the fire D the Sun

1 marks

Answer: D

This question in 0653/22 Feb/March 2019

13 Which term is defined as a unit containing all of the organisms and their environment, interacting with each other? A carbon cycle B ecosystem C food chain D food web

1 marks

Answer: B

This question in 0653/22 May/June 2019

13 An increased volume of nitrate ions is washed into a lake. Why does this result in a decrease in the number of fish in the lake? A There is a decrease in the decomposition of producers. B There is a decrease in the growth of producers. C There is an increase in aerobic respiration by decomposers. D There is an increase in dissolved oxygen.

1 marks

Answer: C

This question in 0653/21 Oct/Nov 2019

13 The flow diagram shows some stages in the eutrophication of a pond. more … 1 … into water more … 2 … more aerobic respiration by … 3 … reduced dissolved oxygen in water Which words complete gaps 1, 2 and 3? 1 2 3 A decomposers nitrates producers B decomposers producers nitrates C nitrates producers decomposers D nitrates decomposers producers

1 marks

Answer: C

This question in 0653/23 Oct/Nov 2019

12 What is defined as all of the organisms and their environment interacting together in a given area? A ecosystem B food chain C food web D trophic levels

1 marks

Answer: A

This question in 0653/21 May/June 2020

13 Eutrophication results in the death of aquatic organisms. What is a stage in this process? A reduced aerobic respiration by decomposers B reduced decomposition after death of producers C reduced growth of producers D reduced levels of dissolved oxygen

1 marks

Answer: D

This question in 0653/21 Oct/Nov 2020

13 The diagram shows the trophic levels of a food chain. producer herbivore carnivore carnivore    1st trophic 2nd trophic 3rd trophic 4th trophic level level level level Why do most food chains not have more than four trophic levels? A There are too many carnivores in the 3rd trophic level. B There are too many herbivores in the 2nd trophic level. C There is no energy transferred from the 2nd trophic level to the 3rd trophic level. D There is not enough energy available to be transferred to a 5th trophic level.

1 marks

Answer: D

This question in 0653/22 Oct/Nov 2020

12 In which food chain does the final consumer receive the most energy from the producer? primary secondary tertiary quaternary A producer     consumer consumer consumer consumer primary secondary tertiary B producer    consumer consumer consumer primary secondary C producer   consumer consumer primary D producer  consumer

1 marks

Answer: D

This question in 0653/23 May/June 2021

13 In the process of eutrophication, what causes the increased growth of producers? A increased carbon dioxide availability B increased decomposition C increased nitrate ion availability D increased oxygen availability

1 marks

Answer: C

This question in 0653/21 May/June 2022

12 A woodland consists of trees, other plants and animals. Which term describes this woodland and the interaction of its living things with each other and their environment? A ecosystem B food web C habitat D trophic level

1 marks

Answer: A

This question in 0653/22 Feb/March 2023

13 Eutrophication of fresh water occurs because of a series of events in the water. The list describes these events. 1 increased aerobic respiration by decomposers 2 increased availability of nitrate and other ions 3 increased decomposition after death of producers 4 increased growth of producers 5 reduction in amount of dissolved oxygen in the water Which order of these events results in the death of fish and other aquatic organisms? A 2  1  4  5  3 B 2  4  3  1  5 C 4  2  3  1  5 D 4  5  2  1  3

1 marks

Answer: B

This question in 0653/22 May/June 2023

13 Which factors reduce the possible number of trophic levels in a food chain? 1 energy lost in faeces 2 energy absorbed by a plant leaf 3 energy released by respiration 4 energy stored in an animal A 1 and 2 B 1 and 3 C 2 and 4 D 3 and 4

1 marks

Answer: B

This question in 0653/21 Oct/Nov 2024

11 Which term describes an area that contains all the organisms and their environment interacting together? A community B ecosystem C food chain D food web

1 marks

Answer: B

This question in 0653/21 May/June 2025

13 What is an ecosystem? A a network of inter-connected food chains B a specific area in which a plant or an animal lives C all the plants and animals that live within a specific area D the interactions between all living organisms and their environment, in a specific area

1 marks

Answer: D

This question in 0653/23 May/June 2025

12 What is an example of an ecosystem? A all the animals in an ocean B all the organisms and their environment in a desert C all the plants and their environment in a lake D all the trees in a forest

1 marks

Answer: B

This question in 0653/21 Oct/Nov 2025

13 What is described as a community of organisms and their environment interacting together? A ecosystem B food chain C food web D habitat

1 marks

Answer: A

This question in 0653/23 Oct/Nov 2025