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Ocean Depths

Name: 
Date: 

Instructions: Deep sea knowledge, trenches, and marine science

  1. 1.

    What is the deepest known point in the world's oceans?

    A
    Puerto Rico Trench
    B
    Tonga Trench
    C
    Java Trench
    D
    Challenger Deep
  2. 2.

    Who was the first person to reach the bottom of the Mariana Trench in 1960?

    A
    Jacques Cousteau
    B
    Sylvia Earle
    C
    Jacques Piccard and Don Walsh
    D
    Robert Ballard
  3. 3.

    What percentage of the ocean floor has been mapped in detail?

    A
    About 5%
    B
    About 25%
    C
    About 75%
    D
    About 50%
  4. 4.

    What is the name for the region of the ocean where sunlight cannot penetrate?

    A
    Twilight zone
    B
    Pelagic zone
    C
    Aphotic zone
    D
    Benthic zone
  5. 5.

    What phenomenon allows deep-sea creatures to produce their own light?

    A
    Fluorescence
    B
    Chemiluminescence
    C
    Phosphorescence
    D
    Bioluminescence
  6. 6.

    Which ocean is the deepest on average?

    A
    Pacific Ocean
    B
    Arctic Ocean
    C
    Indian Ocean
    D
    Atlantic Ocean
  7. 7.

    What are hydrothermal vents on the ocean floor commonly called?

    A
    Sea geysers
    B
    Deep bubblers
    C
    Ocean volcanoes
    D
    Black smokers
  8. 8.

    What is the largest structure built by living organisms on Earth?

    A
    The Appalachian Mountains
    B
    The Amazon rainforest
    C
    The Great Barrier Reef
    D
    The Sahara Desert
  9. 9.

    At what depth does the 'midnight zone' of the ocean begin?

    A
    200 meters (660 feet)
    B
    1,000 meters (3,300 feet)
    C
    2,000 meters (6,600 feet)
    D
    500 meters (1,640 feet)
  10. 10.

    What is the Mid-Atlantic Ridge?

    A
    An undersea mountain range
    B
    A coral reef system
    C
    A submarine canyon
    D
    A deep ocean trench
  11. 11.

    Which deep-sea fish is known for the bioluminescent lure dangling from its head?

    A
    Gulper eel
    B
    Viperfish
    C
    Lanternfish
    D
    Anglerfish
  12. 12.

    What causes ocean tides?

    A
    Wind patterns
    B
    Underwater volcanic activity
    C
    Earth's rotation alone
    D
    Gravitational pull of the Moon and Sun
  13. 13.

    What is the deepest-living fish ever discovered?

    A
    Barreleye fish
    B
    Giant oarfish
    C
    Hadal snailfish
    D
    Coelacanth
  14. 14.

    What is the Great Blue Hole off the coast of Belize?

    A
    An underwater volcano
    B
    A coral reef formation
    C
    A deep ocean trench
    D
    A giant underwater sinkhole
  15. 15.

    What extreme condition, besides darkness, do creatures face in the deepest parts of the ocean?

    A
    Extreme heat
    B
    Toxic oxygen levels
    C
    Strong ocean currents
    D
    Crushing water pressure

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