Quiz on Seawater Dissolved Substances

The proportion of dissolved substances in seawater is usually expressed in

• parts per hundred.

• parts per thousand.

• parts per ten thousand.

• parts per million.

Which of the following is a source of dissolved substances in the ocean?

• chemical weathering of rocks

• evaporation of water from the seas and ocean

• excretions from marine organisms

• melting icebergs and sea ice

How do elements such as chlorine, bromine, sulfur, and boron get into the ocean?

• runoff from rivers and streams

• excretions from marine organisms

• volcanic eruptions

• chemical weathering of rocks

Which of the following processes does NOT decrease the salinity of seawater?

• runoff

• solar radiation

• evaporation

• weathering

Differing amounts of solar radiation across Earth’s latitude affect the ocean’s

• salinity in the thermocline.

• density at the surface.

• temperature at the surface.

• density in the thermocline.

Which of the following occurs when the ocean’s salinity increases?

• Density increases.

• Density decreases.

• Temperature increases.

• Temperature decreases.

Which of the following is the most important factor affecting seawater density?

• chemical weathering

• solar radiation

• temperature

• latitude

At least 80 percent of ocean water is included in the

• transition zone

• thermocline

• surface mixed zone

• deep zone

The three-layered structure of the open ocean does NOT exist

• in middle latitudes

• in high latitudes

• in low latitudes

• at the equator

Marine organisms can be classified according to