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Approximately how much of Earth's surface is covered by water?
The largest of Earth's oceans is the _____.
What technology do scientists use to measure ocean depth?
Which of the following is NOT one of the three major regions of the ocean floor?
The gently sloping submerged surface extending from the shoreline toward the deep ocean is called the _____.
Which part of the ocean is deepest?
Approximately how much of Earth's surface is covered by land?
200 years ago
Approximately when did the ocean become an important area of study?
Which of the following is NOT considered one of the four major oceans?
Where trenches do not exist, the steep continental slope merges into a more gradual incline known as the continental ____.
Deep, steep-sided valleys that originate on the continental slope and may extend to the ocean basin floor are called ____.
Isolated volcanic peaks on the ocean floor are called ____.
They are geologically very stable.
Which of the following is NOT true about deep ocean trenches?
Which ocean has the greatest average depth?
Which of the following is NOT an energy resource obtained from the ocean?
The Persian Gulf, the Gulf of Mexico, and the North Sea are all known for their reserves of what ocean resource?
sand and gravel
Which ocean resources are second in economic value to oil?
parts per thousand
Ocean salinity is usually expressed in _____.
What is the principal source of dissolved substances in the oceans?
The ocean layer of rapid temperature change with depth is known as the _____.
Calcareous ooze is an example of ____.
Manganese nodules are an example of ____.
What type of sediment forms from minerals that crystallize from seawater?
How much of the world's oil production currently comes from offshore regions?
oil and natural gas
Heat from Earth's interior and pressure from overlying rock transform the remains of marine sediments into ____.
They rapidly break down at surface temperatures and pressures.
What is one disadvantage of using gas hydrates?
Which of the following is NOT an ocean resource?
the salts precipitate out of solution
When seawater evaporates, the concentration of salts increases until which of the following occurs?
nutrients and sunlight
What factors influence a region's photosynthetic productivity?
Which term best describes energy transfer between trophic levels?
Where would a primary producer be located in a food chain?
What is the salinity of seawater?
What is the most abundant salt in the sea?
Most ocean water is located in which zone?
Which of the following properties most determines water's vertical position in the ocean?
Which of the following is NOT a category of marine organisms?
Which of the following is a type of plankton?
Which of the following is a type of nekton?
They feed on each other.
How do animals survive in the deeper parts of the seafloor?
The horizontal distance between two successive crests is called the _____.
As the speed and length of a wave decrease, the wave _____.
Which tidal pattern has two high tides and two low tides each day?