Hydrosphere - Practice Test 4

Attempt the quiz above first, then review every question with its correct answer and a short explanation below.

1. Q1.Gyres are:

   • A.Large systems of circulating ocean currents✓ Correct Answer
   • B.Tornadoes
   • C.Coral reefs
   • D.Fish

   Explanation: Circular patterns of currents.

2. Q2.Which zone of the ocean is dark (no light)?

   • A.Aphotic Zone✓ Correct Answer
   • B.Photic Zone
   • C.Euphotic Zone
   • D.Surface Zone

   Explanation: Below 200m-1000m.

3. Q3.The deepest trench in the Atlantic Ocean is:

   • A.Puerto Rico Trench✓ Correct Answer
   • B.Mariana Trench
   • C.Java Trench
   • D.Tonga Trench

   Explanation: Approx 8,376 meters deep.

4. Q4.Which current flows around Antarctica?

   • A.West Wind Drift (Antarctic Circumpolar)✓ Correct Answer
   • B.Gulf Stream
   • C.Kuroshio
   • D.Agulhas

   Explanation: Moves west to east around the continent.

5. Q5.Sea mounts are:

   • A.Underwater mountains (volcanic)✓ Correct Answer
   • B.Islands
   • C.Coral reefs
   • D.Trenches

   Explanation: Volcanic peaks that don't break the surface.

6. Q6.Guyots are:

   • A.Flat-topped seamounts✓ Correct Answer
   • B.Trenches
   • C.Currents
   • D.Fish

   Explanation: Eroded seamounts.

7. Q7.The Red Sea gets its name from:

   • A.Algal blooms (Trichodesmium)✓ Correct Answer
   • B.Red rocks
   • C.Blood
   • D.Red coral

   Explanation: Cyanobacteria turn the water reddish-brown.

8. Q8.Which canal connects the Pacific and Atlantic oceans?

   • A.Panama Canal✓ Correct Answer
   • B.Suez Canal
   • C.Kiel Canal
   • D.Erie Canal

   Explanation: Repeated concept: Panama.

9. Q9.Salinity is expressed as parts per:

   • A.Thousand (ppt)✓ Correct Answer
   • B.Hundred
   • C.Million
   • D.Ten

   Explanation: Grams of salt per kg of water.

10. Q10.Warm currents flow from:

    • A.Equator to Poles✓ Correct Answer
    • B.Poles to Equator
    • C.East to West only
    • D.West to East only

    Explanation: They carry warm water from the equator poleward.

11. Q11.Cold currents flow from:

    • A.Poles to Equator✓ Correct Answer
    • B.Equator to Poles
    • C.Land to Sea
    • D.Sea to Land

    Explanation: They carry cold water equatorward.

12. Q12.The Canary Current is:

    • A.Cold✓ Correct Answer
    • B.Warm
    • C.Freshwater
    • D.Wind

    Explanation: Cold current off NW Africa.

13. Q13.The Mozambique Current is:

    • A.Warm✓ Correct Answer
    • B.Cold
    • C.Neutral
    • D.Frozen

    Explanation: Warm current in the Indian Ocean.

14. Q14.The densest water in the oceans is found in:

    • A.Bottom / Deep zone✓ Correct Answer
    • B.Surface
    • C.Thermocline
    • D.Coastal

    Explanation: Cold and salty water sinks to the bottom.

15. Q15.Which ocean has the most trenches?

    • A.Pacific✓ Correct Answer
    • B.Atlantic
    • C.Indian
    • D.Arctic

    Explanation: Ring of Fire subduction zones.

16. Q16.Upwelling brings:

    • A.Nutrients from depth to surface✓ Correct Answer
    • B.Warm water down
    • C.Sand
    • D.Oil

    Explanation: Supports fish populations.

17. Q17.Tidal range is:

    • A.Difference in height between high and low tide✓ Correct Answer
    • B.Distance of tide
    • C.Speed of tide
    • D.Time of tide

    Explanation: Vertical difference.

18. Q18.The Bay of Fundy is famous for:

    • A.Highest tides in the world✓ Correct Answer
    • B.Coral reefs
    • C.Sharks
    • D.Calm water

    Explanation: Located in Canada, tides can reach 16m.

19. Q19.Coral polyps live in symbiosis with:

    • A.Zooxanthellae (Algae)✓ Correct Answer
    • B.Fish
    • C.Whales
    • D.Sharks

    Explanation: Algae provide food/color.

20. Q20.The largest coral reef in India is:

    • A.Lakshadweep (Atolls)✓ Correct Answer
    • B.Andaman
    • C.Gulf of Kutch
    • D.Gulf of Mannar

    Explanation: Lakshadweep is entirely coral.