NAUI Marine Environment & Ecology

Question 1

Which ocean zone receives sufficient sunlight to support photosynthesis?

Accepted Answer

Euphotic zone

Answer

The euphotic zone extends from the surface to approximately 200 meters and receives enough sunlight for photosynthesis to occur.

Question 2

What are the primary producers at the base of most marine food chains?

Accepted Answer

Phytoplankton

Answer

Phytoplankton are microscopic photosynthetic organisms that form the foundation of nearly all marine food webs.

Question 3

What is a coral reef primarily composed of?

Accepted Answer

Calcium carbonate skeletons secreted by coral polyps

Answer

Coral reefs are built from accumulated calcium carbonate (limestone) skeletons secreted by tiny coral polyps over thousands of years.

Question 4

Which type of ecological relationship exists between clownfish and sea anemones?

Accepted Answer

Mutualism

Answer

Clownfish and anemones share a mutualistic relationship — the fish gains shelter and the anemone benefits from the fish's cleaning behavior and waste nutrients.

Question 5

What is the thermocline?

Accepted Answer

A layer where temperature rapidly decreases with increasing depth

Answer

The thermocline is a distinct ocean layer where water temperature decreases rapidly with depth, separating warm surface water from colder deep water.

(NAUI) National Association of Underwater Instructors Certification Practice Test

(NAUI) National Association of Underwater Instructors Certification Practice Test

NAUI Marine Environment & Ecology