Chapter 14 Study Guide: Ocean Zones
Learning about the Ocean
1. About 70% of earth is covered by the ocean floor.
2. HMS Challenger marked the beginning of the modern science of
oceanography
3. Ancient people study the ocean to learn about sources of food, learning
about routes for trade and travel, and curiosity of the unknown.
4. It is difficult to study the ocean floor because it is very cold, very dark, and
under high pressure.
5. Sonar is a type of technology that uses sound waves to determine the depth
of the ocean floor.
6. Types of technology:
SCUBA, Sonar, Submersibles, Remote underwater manipulators,
Satellites, Deep Flight aviators
The Ocean Floor
1. Be able to label the 7 parts of the ocean floor: Continental shelf, continental
slope, abyssal plain, trench, mid-ocean ridge, seamount, volcanic island
2. The deepest trench on Earth is the Mariana Trench. It is 11km.
Life in the Ocean
1. Scientists classify marine organisms according to where they live and how
they move
2. The three categories of ocean organisms are plankton, benthos, and nekton.
3. Plankton are organisms that float and are carried by the waves of currents;
benthos are organisms that live on the ocean floor; nekton are freeswimming animals.
4. Examples of plankton: crustaceans, young fish, krill, algae, mollusks
Examples of benthos: crabs, lobster, sponges
Examples of nekton: dolphin, stingray, fish, shark
Ocean Zones
1. Intertidal, Neritic, Open-Ocean (Surface, Transition, Deep)
2. Intertidal: an area that stretches from the highest high tide line on land out
to the point of the lowest low tide on the continental shelf. Neritic: the area
that extends to the lowest low tide line out to the edge of the continental
shelf. Open-Ocean: the deepest, darkest area of the ocean beyond the edge
of the continental shelf.
3. The Neritic Zone has the widest variety of organisms.
4. The Deep Zone of the Open-Ocean Zone has the smallest variety of living
organisms because of its harsh conditions.
Intertidal Zone
1. The organisms of intertidal zone must be able to tolerate changes in salinity
and temperature, as well as, periods underwater, periods of no water only
air, and must cling on to rocks when there are pounding waves.
2. Name and describe 6 of the habitats of this zone:
Estuaries: inlets or bays where fresh water and salt water mix.
Mangrove forests: grow in coastal wetlands and have short, gnarled trees
with arching roots.
Salt marshes: very muddy, rich in nutrients, and has cordgrass for food and
protection. Cordgrass is the most common plant in the salt marshes.
Sandy shores: the sand is always moving and animals burrow underground
for protection.
Rocky shores: strong winds, crashing waves, harsh sun and animals must
hold tightly to rocks.
Tide pools: puddles left behind from the tide, big changes in temperature
and salinity.
Neritic Zone
1. The neritic zone receives sunlight and a steady supply of nutrients washed
from the land into the ocean. Major fisheries are located here.
2. Two Habitats
Coral Reefs: made of living coral and the hard outer layer they leave behind
when they die.
Kelp Forests: large, heavy algae that produce their own food. They only grow
in cold neritic water over a rocky floor.
Open-Ocean Zone
1. Conditions in each layer:
Surface: sunlit, algae grow here, more organisms than the deeper zone.
Transition: ends about 1 k m below the surface of the water and conditions
begin to change here
Deep: Very cold, dark, and high pressure, little food and fewer organisms
live here.
2. Characteristics of animals here:
Bioluminescence: organism that produce their own light
Large mouths
large eyes
Good hunters
Sharp teeth
3. Hydrothermal vent: this is when hot water rises up from the cracks in the
ocean floor having been heated by magma beneath the ocean floor.