Test Your Understanding of
the World’s Oceans
World Oceans Day is Saturday, June 8.
Since 2002, World Oceans Day has been celebrated to promote global involvement in protecting our oceans and sustainably managing oceanic resources.
But how much do you really know about the briny deep? Take our mini-quiz and find out.
(Answers are below, but no fair peeking!)
#1. What are the names of the world’s five oceans?
A. North Atlantic, South Atlantic, North Pacific, South Pacific, and Indian
B. Atlantic, Pacific, Indian, Arctic, and Southern
C. Atlantic, Pacific, Arctic, Antarctic, and Southern
D. Atlantic, Pacific, Mediterranean, Baltic, and South China
E. North Atlantic, South Atlantic, North Pacific, Southern, and Indian
#2. How much of the earth’s surface is covered by ocean?
A. 60%
B. 85%
C. 96%
D. 71%
E. 40%
#3.The blue whale is the world’s largest animal. What else is it known for?
A. It’s the world’s loudest animal
B. It’s the world’s fastest sea animal
C. It’s one of the world’s quietest animals
D. It’s the world’s heaviest animal
E. Both A and D
#4. What is the name and oceanic location of the world’s deepest marine trench?
A. Puerto Rico Trench in the Atlantic
B. Molloy Hole in the Arctic Ocean
C. Mariana Trench in the Pacific
D. South Sandwich Trench in the Southern Ocean
E. Java Trench in the Indian Ocean
#5. The oceans are an amazing food source, but which of the following fish can kill you after it’s been caught and cooked?
A. Great white shark
B. Swordfish
C. Blowfish
D. Sea lamprey
E. Blobfish
#6. How much of the oxygen we breathe is generated by the oceans?
A. About two-thirds
B. More than half
C. About one-third
D. Nearly all
E. None
Answers
#1. Answer: B. North Atlantic, South Atlantic, North Pacific and South Pacific are designations for the modern “Seven Seas,” but are not recognized as oceans. Mediterranean, Baltic and South China are also identified as “seas,” smaller than oceans and typically located where land and ocean meet. Prior to this century, only four oceans were globally recognized. In 2000, the International Hydrographic Organization officially recognized the Southern (or Antarctic) Ocean as a distinct ocean. But it wasn’t until June 8, 2021 (World Oceans Day), that the National Geographic Society officially designated the Southern Ocean as a separate oceanic entity.
#2. Answer: D. About 71% of the earth’s surface is covered by ocean, although only 20% of the ocean’s total volume is visible to us on the surface. An additional 2.5% of the earth is covered by freshwater sources: ice caps, lakes, rivers, etc.
#3. Answer: C. The Mariana Trench in the Pacific Ocean is almost 7 miles deep, which means it would swallow up Mt. Everest — with a mile to spare. The depths of the other major oceanic trenches are: Puerto Rico Trench, 5.2 miles; South Sandwich Trench, 4.6 miles; Java Trench, 4.5 miles; and Molloy Hole, 3.5 miles. Collectively, all of these trenches are known as the “five deeps,” as they are the deepest spots in each of the world’s five oceans.
#4. Answer: E. The blue whale is the largest, heaviest and loudest animal on the planet. Blue whales are about as long as three school buses, and they weigh between 200,000 to 300,000 pounds. (The heart of the blue whale alone is the size of a small car). The whale’s low-frequency whistle measures 188 decibels; it’s louder than a jet engine and can be heard hundreds of miles away. (The world’s fastest sea animal, on the other hand, is the sailfish.)
#5. Answer: C. The blowfish contains enough poison to kill 30 adult humans. Only a few places in the world consider it a delicacy worth preparing, most notably Japan. Chefs must be specially licensed to prepare blowfish, as the slightest mistake would be fatal.
#6. Answer: B. More than half of the oxygen we breathe comes from marine photosynthesizers, like phytoplankton and seaweed. Both use carbon dioxide, water and energy from the sun to make food for themselves, releasing oxygen in the process. And they do it in the ocean.
Sources:
Featured Image: Adobe, License Granted
National Geographic
Science Direct
Britannica
USGS
National Ocean Service