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

Ocean Depth Zones

Science · Ocean Life · ages 7-9
Name ______________________   Date ____________

  1. Which of these ocean zones receives no sunlight?

    • Twilight zone
    • Midnight zone
    • Sunlight zone

  2. During daytime, which ocean zone is closest to the surface and receives the most sunlight?

    • Sunlight zone
    • Twilight zone
    • Midnight zone

  3. During daytime, sunlight gets weaker as you travel down from the sunlight zone through the twilight zone to the midnight zone.

    Circle one:   True   False

  4. Seaweed needs sunlight to make food and grow. Which zone gives it enough sunlight?

    • Sunlight zone, with bright sunlight for making food
    • Midnight zone, where darkness helps it make its food
    • Twilight zone, where dim sunlight is enough for its food

  5. Use the descriptions. Which zone still receives some sunlight, but only a dim amount?

    Sunlight: brightTwilight: dimMidnight: no sunlight
    • Sunlight zone
    • Midnight zone
    • Twilight zone

  6. A research submarine travels down from the surface to the midnight zone. In which order does it pass through the three studied zones?

    • Midnight, then twilight, then sunlight
    • Sunlight, then twilight, then midnight
    • Twilight, then sunlight, then midnight

  7. In a made-up daytime example, sunlight readings are 8 units near the surface, 3 in the twilight zone, and 0 in the midnight zone. How many units does the reading drop from the surface to the midnight zone?

    Surface8Twilight3Midnight0

    Answer: ______________

  8. Jake says, 'Seaweed can make food from sunlight in the midnight zone.' Which fact helps him check this idea?

    • Bright sunlight reaches the midnight zone for seaweed to use.
    • Seaweed can make food from sunlight even where none arrives.
    • No sunlight reaches the midnight zone.
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Answer key

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

Ocean Depth Zones W1-mt_sQpIV0-qY7-s1

  1. Midnight zone · No sunlight reaches the midnight zone. Animals and submarine lamps can still give off light there.
  2. Sunlight zone · The sunlight zone is near the surface. It receives more sunlight than the deeper twilight and midnight zones.
  3. True · The journey goes from bright sunlight to dim sunlight and then to water that receives no sunlight.
  4. Sunlight zone, with bright sunlight for making food · The sunlight zone provides enough sunlight for seaweed to make food. The twilight zone has too little, and the midnight zone has none.
  5. Twilight zone · Dim sunlight reaches the twilight zone. The sunlight zone is brighter, while the midnight zone receives no sunlight.
  6. Sunlight, then twilight, then midnight · The submarine begins in the sunlight zone, passes through the twilight zone, and reaches the midnight zone.
  7. 8 · Use the starting reading of 8 and ending reading of 0. The drop is 8 minus 0, or 8 units.
  8. No sunlight reaches the midnight zone. · Seaweed needs sunlight to make food this way. No sunlight reaches the midnight zone, so it cannot make food from sunlight there.
Worksheet · LightMySky