• Organisms that can move independently of
ocean currents by swimming or other means
• The forms of marine life that live on or in the
• The upper part of the ocean into which
• The area where land and sea meet and
overlap; the zone between high and low tides.
• The marine-life zone that extends from
the low-tide line out to the shelf break.
• The marine-life zone beyond the continental
• Open ocean of any depth; animals in this zone
swim or float freely.
• Othe marine-life zone that includes any sea-
bottom surface regardless of its distance from
• A subdivision of the benthic zone
characterized by extremely high pressures,
low temperatures, low oxygen, few nutrients,
and no sunlight.
• How can marine organisms be
–Marine organisms can be classified
according to where they live and how
• What is the difference between
plankton and nekton?
–Plankton drift with ocean currents and
Nekton swim independently of the
• In which area of the ocean can most
benthos organisms be found living?
–Most benthos organisms are living on
or in the ocean bottom.
• What factors are used to divide the
ocean into marine life zones?
–Three factors are used to divide the
ocean into distinct marine life zones:
the availability of sunlight, the distance
from shore, and water depth.