Hydrosphere

What role do estuaries play in Earth's oceans?

• They are primary sources of ocean pollution.

• They prevent upwelling.

• They serve as the combination of river water and ocean water.

Which of the following is a characteristic of marine ecosystems?

• Rich in nutrients and minerals

• High levels of pollutants

• Absence of dissolved gases

• Lack of biodiversity

What is upwelling?

• A process that decreases nutrient levels in ocean waters

• The rising of deep, cold, nutrient-rich water to the surface

• The movement of warm water to ocean surfaces

• A phenomenon that increases the temperature of ocean waters

How do gases behave in the marine environment?

• Gases dissolve more readily in colder waters.

• Gases do not dissolve in ocean waters.

• Gases dissolve more readily in warmer waters.

• Gases are completely absent in the marine environment.

Why are few plants found on the bottom floor of the ocean?

• Floor has decomposers
• Sunlight doesn't reach the floor
• Water is a limiting factor
• Temperature is low

What is a key feature of marine ecosystems not found in freshwater ecosystems?

• Salinity levels

• Soil types

• Air humidity

Which is the correct combination of water in the earth's hydrosphere?

• 50% ocean and 50% fresh water

• 97% ocean water and 3% freshwater

• 97% freshwater and 3% ocean water

Most of earth's fresh water is contained in

• the ocean

• lakes

• glaciers and poles

Fish populations will increase in

• areas of calm waters

• areas of upwelling

• hot water

Excess nitrates and phosphates will

• have no effect on a marine ecosystem

• increase nutrients in a marine ecosystem

• decrease nutrients in a marine ecosystem