Marine Biology & Conservation Flashcards
7 cards from real PADI practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Marine Biology & Conservation flashcards as text
Which chemical process is causing ocean pH to decrease over time, threatening shell-forming marine organisms?
Answer: Ocean acidification from CO₂ absorption
Oceans absorb about 30% of atmospheric CO₂, which reacts with seawater to form carbonic acid, lowering pH and reducing carbonate ions needed for shells and skeletons.
What role do mangrove forests play in marine ecosystems?
Answer: They serve as nursery habitats, storm buffers, and carbon sinks
Mangroves provide critical nursery habitat for juvenile fish and invertebrates, protect coastlines from storm surge erosion, and sequester large amounts of carbon.
What is bioluminescence in marine organisms, and which group is well known for this ability?
Answer: Light production through chemical reactions; dinoflagellates and deep-sea fish
Bioluminescence is the biological production of light via chemical reactions (luciferin-luciferase); dinoflagellates, anglerfish, and many deep-sea creatures use it for attraction, defense, or communication.
Which diving practice causes the most physical damage to coral reefs during recreational diving?
Answer: Poor buoyancy control leading to contact with corals
Divers with poor buoyancy control accidentally contact and break coral polyps, which take decades to grow; even brief touches can introduce bacteria and disease.
What is the significance of 'upwelling' in marine ecosystems?
Answer: It brings cold, nutrient-rich water to the surface, supporting high productivity
Upwelling brings deep, cold, nutrient-rich water to sunlit surface layers, fueling phytoplankton blooms and supporting highly productive fisheries and marine food webs.
A PADI diver notices starfish missing arms but still alive on a reef. What natural process does this likely indicate?
Answer: Regeneration — sea stars can regrow lost limbs
Sea stars (starfish) have remarkable regenerative abilities and can regrow lost arms; some species can even regenerate an entire body from a severed arm.
Why is it important for divers to avoid touching or feeding wild marine life?
Answer: It disrupts natural behaviors, can cause disease transmission, and makes animals dependent on humans
Feeding and touching marine life alters natural feeding behaviors, can spread disease, causes stress responses, and conditions wild animals to associate humans with food, often leading to aggression.