Coral Reefs Trivia Quiz – 15 Questions And Answers

Embark on a vibrant underwater expedition with our Coral Reefs Trivia Quiz! This quiz will immerse you in the enchanting world of coral reefs, showcasing their extraordinary beauty, biodiversity, and ecological significance. Get ready to discover the secrets of these underwater wonders and test your knowledge of these delicate ecosystems.

Prepare to explore the stunning colors, diverse marine life, and ecological importance of coral reefs. Each question will delve into different aspects, from the symbiotic relationships between corals and their resident organisms to the threats and conservation efforts aimed at preserving these fragile ecosystems.

Are you ready to test your knowledge, learn fascinating facts, and become an advocate for the protection of coral reefs? Let’s embark on this marine adventure and see if you have what it takes to be a true champion of these underwater marvels!

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  1. What percentage of marine species are found in coral reefs?
    • 50%
    • 25%
    • 10%
    • 75%
    The correct answer is 25%.
    Coral reefs are home to an estimated 25% of all marine species, making them one of the most biodiverse ecosystems on Earth.
  2. How much of the Earth’s surface do coral reefs cover?
    • 1%
    • 10%
    • 5%
    • 0.1%
    The correct answer is 0.1%.
    Coral reefs only cover around 0.1% of the Earth’s surface, but they support a vast amount of marine life.
  3. What is the largest coral reef system in the world?
    • Sunda Shelf
    • Mesoamerican Barrier Reef
    • Red Sea Coral Reef
    • Great Barrier Reef
    The correct answer is Great Barrier Reef.
    The Great Barrier Reef, located off the coast of Australia, is the largest coral reef system in the world, stretching over 2,300 kilometers.
  4. What is the primary source of food for coral polyps?
    • Seaweed
    • Fish
    • Zooxanthellae
    • Plankton
    The correct answer is Zooxanthellae.
    Zooxanthellae are microscopic algae that live within coral polyps and provide them with their primary source of food through photosynthesis.


  1. Which of these factors does not contribute to coral bleaching?
    • Warm water temperatures
    • Cold water temperatures
    • Pollution
    • Ocean acidification
    The correct answer is Cold water temperatures.
    Coral bleaching is primarily caused by warm water temperatures, ocean acidification, and pollution.
  2. Which of these is not a type of coral?
    • Soft coral
    • Finger coral
    • Stony coral
    • Tree coral
    The correct answer is Tree coral.
    There are two main types of coral: stony coral and soft coral. Tree coral is not a recognized type of coral.
  3. What is the main cause of coral reef destruction worldwide?
    • Natural disasters
    • Disease
    • Human activities
    • Predators
    The correct answer is Human activities.
    Human activities, such as overfishing, pollution, and climate change, are the main cause of coral reef destruction worldwide.
  4. What is the term for the process by which coral reefs grow?
    • Coral calcification
    • Coral budding
    • Coral spawning
    • Coral metamorphosis
    The correct answer is Coral calcification.
    Coral calcification is the process by which coral reefs grow, as coral polyps extract calcium from seawater and combine it with carbon dioxide to form calcium carbonate skeletons.
  5. Which of these animals is a natural predator of coral?
    • Clownfish
    • Crown-of-thorns starfish
    • Sea urchin
    • Sea turtle
    The correct answer is Crown-of-thorns starfish.
    The crown-of-thorns starfish is a natural predator of coral, as it feeds on coral polyps.
  6. What is the name of the process by which corals reproduce sexually?
    • Fragmentation
    • Fission
    • Broadcast spawning
    • Budding
    The correct answer is Broadcast spawning.
    Broadcast spawning is the process by which corals reproduce sexually, releasing eggs and sperm into the water column to fertilize and form new coral larvae.
Reveal Answers 1 To 10
  1. What is the primary function of coral mucus?
    • Structural support
    • Food source
    • Protection from pathogens
    • Reproduction
    The correct answer is Protection from pathogens.
    Coral mucus serves as a protective barrier against pathogens and helps to remove debris from the coral surface.
  2. Which of these elements is not a major component of coral skeletons?
    • Silicon
    • Carbon
    • Calcium
    • Magnesium
    The correct answer is Silicon.
    Coral skeletons are primarily composed of calcium, carbon, and magnesium in the form of calcium carbonate.
  3. What is the term for the symbiotic relationship between coral polyps and zooxanthellae?
    • Amensalism
    • Commensalism
    • Mutualism
    • Parasitism
    The correct answer is Mutualism.
    The relationship between coral polyps and zooxanthellae is an example of mutualism, as both organisms benefit from the partnership.
  4. Which of these is not a threat to coral reefs caused by climate change?
    • Sea level rise
    • Ocean acidification
    • Increased sunlight penetration
    • Increased storm intensity
    The correct answer is Increased sunlight penetration.
    Climate change threatens coral reefs through sea level rise, increased storm intensity, and ocean acidification, but not increased sunlight penetration.


  1. Which of these marine animals does not rely on coral reefs for habitat?
    • Dolphin
    • Parrotfish
    • Sea turtle
    • Clownfish
    The correct answer is Dolphin.
    Dolphins do not rely on coral reefs for habitat, as they are typically found in open ocean environments. Clownfish, sea turtles, and parrotfish all depend on coral reefs for shelter and food sources.
Reveal Answers 11 To 15



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