PADI The Aquatic Environment 3

Question 1

How does surge affect divers in shallow water near reef structures?

Accepted Answer

Surge pushes divers back and forth, increasing risk of contact with the reef

Answer

Surge in shallow water creates oscillating back-and-forth water movement that can push divers into reef structures, risking injury to both the diver and the reef.

Question 2

Which marine animal's sting is best treated by immersing the affected area in hot water?

Accepted Answer

Stingray

Answer

Stingray venom is protein-based and heat-labile, so hot water (as hot as tolerable) denatures the venom and provides significant pain relief.

Question 3

What does 'thermocline' describe in a diving context?

Accepted Answer

A layer of rapid temperature change between warmer and cooler water

Answer

A thermocline is a distinct horizontal layer in the water where temperature drops sharply over a short vertical distance, often visible as a shimmering distortion.

Question 4

Why is it important for divers to understand prevailing current directions at a dive site?

Accepted Answer

Divers should plan to dive into the current first and return with it

Answer

Diving into the current first conserves energy for the outbound leg, allowing divers to drift back to the exit point when tired during the return.

Question 5

What happens to natural light underwater as depth increases?

Accepted Answer

Red wavelengths are absorbed first, followed by orange, then yellow

Answer

Water selectively absorbs longer wavelengths first: red disappears around 5m, orange around 10m, and yellow around 20m, leaving only blue-green light at greater depths.

PADI - Professional Association of Diving Instructors Practice Test

PADI - Professional Association of Diving Instructors Practice Test

PADI The Aquatic Environment 3