PADI Marine Biology & Conservation 2 — Questions and Answers
Question 1: Which type of coral reproduction involves a coral polyp splitting to create a genetically identical clone?
- Sexual reproduction via spawning
- Asexual budding or division (Correct answer)
- Larval settlement
- Fragmentation from storm damage only
Correct answer: Asexual budding or division
Asexual budding or division allows coral polyps to clone themselves, expanding a colony without the genetic exchange of sexual reproduction.
Question 2: What is the term for the relationship between clownfish and sea anemones, where both organisms benefit?
- Parasitism
- Commensalism
- Mutualism (Correct answer)
- Competition
Correct answer: Mutualism
Mutualism describes the clownfish-anemone relationship: clownfish gain shelter while the anemone benefits from the fish removing parasites and increasing water circulation.
Question 3: Which marine organism is the primary producer at the base of most open-ocean food webs?
- Zooplankton
- Phytoplankton (Correct answer)
- Kelp
- Sea grass
Correct answer: Phytoplankton
Phytoplankton are microscopic photosynthetic organisms that form the foundation of open-ocean food webs by converting sunlight and CO₂ into organic matter.
Question 4: A diver observes a cephalopod rapidly changing skin color and texture. Which animal is most likely being observed?
- Nautilus
- Octopus or cuttlefish (Correct answer)
- Sea slug (nudibranch)
- Flatfish
Correct answer: Octopus or cuttlefish
Octopuses and cuttlefish possess specialized chromatophores and papillae that allow rapid, dynamic color and texture changes for camouflage and communication.
Question 5: What physiological adaptation allows marine mammals such as dolphins to dive repeatedly to depth without suffering decompression sickness?
- They breathe enriched air before diving
- Their lungs collapse at depth, preventing nitrogen absorption (Correct answer)
- They have a higher hemoglobin count that neutralizes nitrogen
- They exhale all air before descending
Correct answer: Their lungs collapse at depth, preventing nitrogen absorption
Marine mammals have flexible ribcages that allow their lungs to collapse under pressure, preventing significant nitrogen uptake and thus avoiding decompression sickness.
Question 6: Which conservation status category, used by the IUCN Red List, indicates a species faces an extremely high risk of extinction in the wild?
- Vulnerable
- Endangered
- Critically Endangered (Correct answer)
- Near Threatened
Correct answer: Critically Endangered
Critically Endangered is the highest risk category before Extinct in the Wild, indicating a species faces an extremely high probability of extinction.
Question 7: What is 'ghost fishing' and why is it harmful to marine ecosystems?
- Fishing at night using lights to attract fish
- Abandoned or lost fishing gear that continues to trap and kill marine life (Correct answer)
- Illegal fishing in protected marine reserves
- The practice of catch-and-release fishing
Correct answer: Abandoned or lost fishing gear that continues to trap and kill marine life
Ghost fishing occurs when lost or abandoned nets, traps, and lines continue to indiscriminately trap and kill fish, sea turtles, marine mammals, and other organisms.
PADI Marine Biology & Conservation 2
Which type of coral reproduction involves a coral polyp splitting to create a genetically identical clone?