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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
  1. What is the function of the lateral line system found in most bony fish?

    Answer: It detects vibrations and water movement changes

    The lateral line is a sensory system of hair cells that detects low-frequency vibrations and pressure changes in surrounding water, aiding navigation and predator/prey detection.

  2. Sea turtles are known to return to the same beach where they were born to nest. What is this behavior called?

    Answer: Natal homing

    Natal homing is the instinctive behavior of sea turtles returning to their birth beach to lay eggs, guided by Earth's magnetic field imprinted at hatching.

  3. Which process describes how nutrients cycle from dead organic matter back into the marine food web?

    Answer: Decomposition by bacteria and fungi

    Decomposition by bacteria and fungi breaks down dead organic matter, releasing nutrients such as nitrogen and phosphorus back into the water for use by phytoplankton.

  4. What term describes zones in the ocean that receive no sunlight and rely on chemosynthesis rather than photosynthesis for energy?

    Answer: Hydrothermal vent communities

    Hydrothermal vent communities thrive in total darkness using chemosynthetic bacteria that convert hydrogen sulfide from vents into organic compounds as an energy source.

  5. Which factor most directly causes seasonal 'dead zones' in coastal waters?

    Answer: Nutrient runoff causing algal blooms and hypoxia

    Agricultural nutrient runoff triggers massive algal blooms; when the algae decompose, bacteria consume oxygen, creating hypoxic dead zones where most marine life cannot survive.

  6. A diver encounters a school of fish that suddenly all turn in the same direction simultaneously. What is this coordinated behavior called?

    Answer: Shoaling and schooling

    Shoaling refers to fish grouping together socially, while schooling describes synchronized, polarized movement, both offering predator confusion and hydrodynamic benefits.

  7. What is the primary purpose of a Marine Protected Area (MPA)?

    Answer: To conserve marine biodiversity by restricting human activities in designated areas

    MPAs are designated ocean areas where human activities are regulated or restricted to protect marine biodiversity, habitats, and ecosystem services.