Food chains and webs

9.If most of the slugs in a food web (lettuce → slug → sparrow) died, what would happen to the lettuce population?

10.Which of the following best describes a food web?

11.What does the arrow in a food chain represent?

12.In an energy pyramid, which trophic level has the most energy?

13.In a food chain, what is the role of a secondary consumer?

14.Which of the following is an example of a producer?

15.In the food chain: lettuce → slug → sparrow → hawk, what is the tertiary consumer?

16.In a food chain, grass → grasshopper → frog → snake, which organism is the secondary consumer?

17.What is the role of a producer in a food chain?

18.In the food chain: lettuce → slug → sparrow → hawk, what is the prey of the sparrow?

19.A student sets up a model ecosystem with two food chains: grass → rabbit → fox and grass → mouse → fox. If a disease kills all the mice, what is the most likely effect on the fox population?

20.In an experiment, a scientist measures the number of organisms at each trophic level in a grassland ecosystem. She finds 1000 grass plants, 200 rabbits, 20 foxes, and 1 eagle. Which statement best explains the decreasing numbers?

21.Which of the following is an omnivore?

22.In a food web, a plant is eaten by a caterpillar, which is eaten by a bird, which is eaten by a cat. The cat is a:

23.A student investigates a pond food web: algae → water flea → small fish → large fish. Which statement about this food web is correct?

24.Which of the following correctly describes a food chain?

25.In a food chain: grass → rabbit → fox, what would be the effect on the grass if the fox population decreases?

26.In the food chain: grass → grasshopper → frog → snake, what is the secondary consumer?

27.In the food chain: lettuce → slug → sparrow → hawk, what would happen to the lettuce population if most of the slugs died?

28.What does an arrow in a food chain represent?

29.In the food web: grass → rabbit → fox and grass → mouse → fox, if a disease kills all the mice, what is the most likely effect on the fox population?

30.In an experiment, a scientist measures the number of organisms at each trophic level in a grassland ecosystem. She finds 1000 grass plants, 200 rabbits, and 20 foxes. Which statement is correct?

31.In a food chain, what is meant by a 'producer'?

32.Which of the following is a herbivore?

33.In the food chain: lettuce → slug → sparrow → hawk, what is the secondary consumer?

34.In a food web, a scientist observes that the number of caterpillars has increased dramatically. Which of the following is most likely to happen as a result?

35.A student sets up two model ecosystems in sealed jars. Jar A contains grass, rabbits, and foxes. Jar B contains grass, rabbits, foxes, and decomposers. After six months, which jar is more likely to have a stable ecosystem?

36.In an experiment, a scientist measures the biomass at each trophic level in a grassland ecosystem. The results show that the biomass of grass is 10,000 kg, the biomass of rabbits is 1,000 kg, and the biomass of foxes is 100 kg. What is the approximate efficiency of energy transfer from the grass to the rabbits?

37.Which of the following is an example of a food chain?

38.In a food web, a pesticide is applied that kills all the insects. Which of the following is the most likely long-term effect on the ecosystem?

39.What is the role of decomposers in a food web?

40.A student constructs a food web: grass → rabbit → fox, and grass → mouse → fox. If a disease kills all the rabbits, what is the most likely effect on the fox population?

41.A herbivore is an animal that eats other animals.

42.In the food chain: grass → grasshopper → frog → snake, which organism is the secondary consumer?

43.Match each term with its correct definition.

44.Arrange the following organisms in the correct order of a food chain, starting with the producer.

45.Which of the following are true about food webs? (Select all that apply)

46.In the food web: grass → rabbit → fox and grass → mouse → fox, if a disease kills all the rabbits, what is the most likely effect on the fox population?

47.In the food chain: lettuce → slug → sparrow → hawk, what is the role of the sparrow?

48.The diagram shows an energy pyramid. Which trophic level contains the greatest amount of energy?

49.Which trophic level in a food chain always contains organisms that can photosynthesise?

50.In a food web, a scientist observes that the population of sparrows has decreased significantly. Which of the following is the most likely direct cause?

51.Complete the sentence using the correct term.

52.State what would happen to the sparrow population if most of the slugs died in the food chain: lettuce → slug → sparrow → hawk.

53.In an energy pyramid, if producers have 10,000 J of energy, and only 10% of energy is passed to each trophic level, how much energy (in J) is available to secondary consumers?

54.In an energy pyramid, if the producers have 50,000 kJ of energy and only 10% of energy is transferred to each trophic level, how much energy (in kJ) is available to the tertiary consumers?

55.Using the food chain: lettuce → slug → sparrow → hawk, state what would happen to the sparrow population if most of the slugs died.

56.In an energy pyramid, the producers have 50,000 kJ of energy. Only 10% of the energy is transferred to each trophic level. How much energy (in kJ) is available to the secondary consumers?

57.Complete the sentence using the correct terms.

58.In an energy pyramid, the producers have 20,000 kJ of energy. Only 10% of the energy is transferred from one trophic level to the next. How much energy (in kJ) is available to the tertiary consumers?

59.Explain why the number of organisms usually decreases at each trophic level in a food chain.

60.In an energy pyramid, if producers have 10,000 J of energy, and only 10% of energy is passed to each trophic level, how much energy (in J) is available to secondary consumers?

61.In an energy pyramid, if the producers have 50,000 kJ of energy and only 10% of energy is transferred to each trophic level, how much energy (in kJ) is available to the tertiary consumers?

62.In an energy pyramid, the producers have 50,000 kJ of energy. Only 10% of the energy is transferred to each trophic level. How much energy (in kJ) is available to the secondary consumers?

63.In an energy pyramid, the producers have 20,000 kJ of energy. Only 10% of the energy is transferred from one trophic level to the next. How much energy (in kJ) is available to the tertiary consumers?