Biology Test Biology Marine Biology & Aquatic Ecosystems 3

Question 1

What is the main cause of ocean acidification?

Accepted Answer

Increased absorption of atmospheric CO2 forming carbonic acid

Answer

The ocean absorbs excess atmospheric CO2, which reacts with seawater to form carbonic acid, lowering ocean pH.

Question 2

Mangrove forests provide which key ecological service in coastal ecosystems?

Accepted Answer

Coastal stabilization, nursery habitat, and carbon sequestration

Answer

Mangroves anchor coastlines against erosion, serve as nurseries for juvenile fish and invertebrates, and sequester large amounts of carbon in their soils.

Question 3

Which term describes organisms that live suspended or swimming in open water, unable to overcome currents?

Accepted Answer

Plankton

Answer

Plankton are organisms that drift with ocean currents and include both phytoplankton (photosynthetic) and zooplankton (heterotrophic).

Question 4

The thermohaline circulation (global ocean conveyor belt) is driven by differences in:

Accepted Answer

Water density due to temperature and salinity

Answer

Thermohaline circulation is driven by density differences caused by varying water temperature (thermo) and salinity (haline) across ocean basins.

Question 5

Eutrophication in aquatic ecosystems is most directly caused by excess:

Accepted Answer

Nitrogen and phosphorus from agricultural runoff

Answer

Excess nitrogen and phosphorus trigger algal blooms; when algae die and decompose, bacterial respiration depletes dissolved oxygen, creating hypoxic dead zones.

Biology Practice Test Practice Test

Biology Practice Test Practice Test

Biology Test Biology Marine Biology & Aquatic Ecosystems 3