Structures for Survival · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

Structures for Survival

Science · Organisms & Life Processes · ages 9-10
Name ______________________   Date ____________

  1. What is the job of the lungs?

    • Pump blood
    • Take in air
    • Grip prey

  2. Which of these is an external structure?

    • Thorns
    • Heart
    • Lungs

  3. A claw is an example of an internal structure.

    Circle one:   True   False

  4. A cow's stomach breaks down tough grass. Is the stomach an internal or external structure?

    • Internal, because it works inside the body
    • External, because it is easy to see
    • Neither, because digestion is not a structure's job

  5. A porcupine is covered in sharp quills. How do the quills help it survive?

    • They help the porcupine climb trees quickly
    • They keep the porcupine warm like a coat of fur
    • They poke predators that get too close

  6. Which sentence best links a structure to a survival function?

    • A deer has legs, and legs are a body part.
    • A deer has long legs, which let it run fast to escape predators.
    • A deer lives in the forest and eats plants.

  7. Sam says: 'The heart takes in air, and the lungs pump blood.' What is wrong with Sam's statement?

    • Sam switched the jobs of the heart and lungs
    • The heart and lungs do not have jobs
    • Nothing, that is correct

  8. Someone writes: 'A bird has wings.' Is this a complete argument for how a structure helps it survive?

    • Yes, naming the structure is enough
    • No, because birds do not have external structures
    • No, it is missing the function the structure performs
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Answer key

For grown-ups. Fold this page away before handing over the rest.

Structures for Survival W1-mt_8VA40Tumth-s1

  1. Take in air · Lungs take in air so the body can get the oxygen it needs.
  2. Thorns · Thorns are on the outside of the plant, so they are an external structure. They protect the plant from being eaten.
  3. False · A claw is on the outside of the body, so it is an external structure, not internal.
  4. Internal, because it works inside the body · The stomach works inside the cow's body, so it is an internal structure that helps digest tough food.
  5. They poke predators that get too close · Sharp quills are an external structure that pokes predators, keeping the porcupine safe.
  6. A deer has long legs, which let it run fast to escape predators. · A strong argument names the structure and explains exactly how it helps the animal survive.
  7. Sam switched the jobs of the heart and lungs · The lungs take in air, and the heart pumps blood. Sam mixed up which structure does which job.
  8. No, it is missing the function the structure performs · A complete argument needs both the structure and the function. Just naming wings does not explain why they matter.
Worksheet · LightMySky