← Back to the activity

Grade 8 Science — Ecosystems and food chains

Separate the living and non-living parts of a habitat, build a food chain, and name the three ways two organisms can live together.

Name: ________________________

  1. 1.In the chain grass → grasshopper → frog → snake, the frogs disappear. What happens to the grasshoppers and the snakes?

    • a) Both stay the same, because the grass is unaffected
    • b) Both increase, because one fewer animal is competing for space
    • c) Grasshoppers increase, because nothing is eating them; snakes decrease, because their food has gone
    • d) Grasshoppers decrease and snakes increase

  2. 2.In the food chain grass → grasshopper → frog → snake, which one is the producer?

    • a) Grasshopper
    • b) Snake
    • c) Frog
    • d) Grass

  3. 3.Food chains in an ecosystem are not really separate. What are they, taken together?

    • a) A population, because the chains hold organisms of the same kind
    • b) A trophic level, because each chain occupies one level
    • c) A community, because the chains share a habitat
    • d) A food web, because an organism may be eaten by two or more kinds of organism

  4. 4.Carrying pollen from the stamens to the carpels — by wind, water, insects, bats or birds — has a one-word name, and fruits and seeds depend on it. What is it?

  5. 5.Sort what you would find in a pond or a forest by whether it is living or not.

    Groups: Biotic · Abiotic

    • Grass
    • Water
    • Soil
    • Sunlight
    • Fish

  6. 6.Match each pair of organisms to the kind of relationship they have.

    • Honeybees and flowers
    • An orchid on a tree branch
    • A tick on a dog
    • parasitism
    • mutualism
    • commensalism

  7. 7.Put these four levels of nature in order, from the smallest upwards.

    • Population
    • Individual
    • Ecosystem
    • Community

  8. 8.Put this grassland food chain in order, from what is eaten first to what eats last.

    • Frog
    • Snake
    • Eagle
    • Grass
    • Grasshopper

Answer key — Grade 8 Science — Ecosystems and food chains

  1. 1. c) Grasshoppers increase, because nothing is eating them; snakes decrease, because their food has gone
  2. 2. d) Grass
  3. 3. d) A food web, because an organism may be eaten by two or more kinds of organism
  4. 4. pollination
  5. 5. Fish → Biotic; Grass → Biotic; Soil → Abiotic; Sunlight → Abiotic; Water → Abiotic
  6. 6. Honeybees and flowers → mutualism; An orchid on a tree branch → commensalism; A tick on a dog → parasitism
  7. 7. 1. Individual 2. Population 3. Community 4. Ecosystem
  8. 8. 1. Grass 2. Grasshopper 3. Frog 4. Snake 5. Eagle