PADI Marine Biology & Conservation 3

Question 1

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

Accepted Answer

It detects vibrations and water movement changes

Answer

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.

Question 2

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

Accepted Answer

Natal homing

Answer

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.

Question 3

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

Accepted Answer

Decomposition by bacteria and fungi

Answer

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.

Question 4

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

Accepted Answer

Hydrothermal vent communities

Answer

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

Question 5

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

Accepted Answer

Nutrient runoff causing algal blooms and hypoxia

Answer

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

(PADI) Certified Professional Association of Diving Instructors Diver Practice Test

(PADI) Certified Professional Association of Diving Instructors Diver Practice Test

PADI Marine Biology & Conservation 3