Instructions: For each of the following questions choose the best answer.
1. Thermohaline circulation refers to
A) Wind-driven currents that flow along the ocean surface.
B) Wind-driven currents that force deeper water to well up to the surface.
C) Wave-driven currents that move water and sand along beaches.
D) Density-driven currents that cause water to sink at high latitudes.
2. The ocean usually appears blue because
A) This is the wavelength of visible light that travels farthest through water.
B) This is the wavelength of light that is scattered by sediment particles.
C) This is the color of the ocean floor, which is visible through the water.
D) This is the color of the sky, where is reflected off of the water.
3. Primary productivity is
A) Uniform throughout the ocean.
B) Generally higher in the centers of the ocean than in the coastal ocean.
C) Highest in northern hemisphere polar latitudes during the northern winter.
D) High where upwelling currents bring nutrients to surface waters.
4. The ocean's primary producers live in the
A) Thermocline.
B) Bathyal zone.
C) Abyssal zone.
D) Photic zone. winter.
D) High where upwelling currents bring nutrients to surface waters.
5. The nutrient content of surface water is often low because
A) The nutrients are consumed by plants.
B) The nutrients evaporate from seawater.
C) The nutrients are broken down by sunlight.
D) The nutrients are produced on the ocean bottom.