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Glossary
Appendix B Glossary
66
Appendix B
Algae Plant like organisms that live mostly in water. Can
exist as single-celled free swimmers or as multicellular
seaweed.
Aphotic Zone Area of the ocean to which sunlight never
reaches; also called the dark zone.
Arthropods Invertebrates that have a hard exoskeleton
and jointed legs.
AUV Autonomous Underwater Vehicle - a machine that
can run independently to perform a certain scientific task.
Bioluminescence Production of light by a living organism,
through chemical reaction, like a firefly, or bacteria, like an
anglerfish.
Camoflauge Ability to blend into the surroundings by
means of body coloration, patterns and shape.
Carapace Part of an exoskeleton that covers the head and
thorax (chest) of some arthropods. Also, a sea turtle shell.
Cartilage Tough, elastic connective and supportive tissue
found in many animals. Some fish, like sharks, have an
entire skeleton made of cartilage.
Cartilaginous Made of cartilage.
Cephalopods Class of marine mollusks which include
octopuses, squids and nautiluses.
Chromatophores Skin cells containing pigment. Some
animals, like squid, ‘move’ pigment and reorient reflective
plates inside chromatophores to change color.
Cnidarians Soft invertebrates with tentacles that have
stinging cells.
Compound Eyes Single eye structure containing several
light-sensing units.
Continental Shelf Gradually sloping area of land that
begins at the shore and continues under the ocean.
Continental Slope Steeply sloping area of land located
beneath the ocean.
Crustaceans Mostly aquatic class of animals that includes
shrimp, lobsters, crabs, krill and others.
Colonial Animal Animal in which many small individuals
grow together, making one large body.
Detritus Small bits of matter, such as decaying plant and
animal parts, and animal waste. Provides food for some
animals living in the deep, lightless regions of the ocean.
Dichotomous Dividing or branching into two parts; in a
dichotomous key, two questions are asked about an item
in order to help classify it.
Dorsal Refers to the back of an organism, such as the
dorsal fin of a fish.
Echinoderms Invertebrates with spiny skin, often in a star
shape, that include sea stars, sea cucumbers and sea
urchins.
Ecology The branch of biology concerned with the
relations between organisms and their environment.
Exoskeleton Hard outer covering of some invertebrates.
Gas Bladder Small gas filled floats that help a plant
or animal float in the water. Gas bladders hold kelp
blades toward the surface where they recieve light.
They also help fish swim upright.
Habitat The area in which a living organism makes
its home.
Invertebrate Animals without a backbone.
Mammals Warm-blooded vertebrates that have hair
and produce milk.
Marine Biology The study of life in the ocean.
Mollusks Invertebrates with soft bodies. Often
protected by shells.
Marine Snow Another name for detritus. See detritus.
Natural History Detailed desciption of a species and
its lifestyle.
Operculum Cover for the opening of the shells of
gastropods (like snails) and, a plate covering the gills
of bony fish.
Overfishing Fishing activities that reduce fish
populations below an acceptable and sustainable
level. Serious depletion of fish stock numbers can
potentially affect the future existence of that species.
Overharvesting Taking too many plants or animals
for human commercial use and potentially affecting
the future existence of that species.
Photic Zone Area of the ocean through which
sunligt penetrates.
Photosynthesis Process which occurs in green
plants where light energy is used to create food.
Phytoplankton Microscopic plants that float near the
ocean’s surface.
Pinniped Group of marine animlas that contain seals
and sea lions.
Preopercle Cover over the smaller gill opening of
bony fish.
Radula File-like structure in mollusks used to tear up
food and bring it into the mouth of the animal.
ROV “Remotely Operated Vehicle”
Runoff Rainfall that is not absorbed by the ground
and flows into the ocean; usually carries with it
pollutants like oil, fertilizers and other materials.
Scavenger Animal that feeds on dead plants or
animals.
Sediment Material that settles to the ocean bottom
such as dirt, dead microorganisms and pollutants.
Siphonophore Colonial animal related to the jellies;
they can grow to be over 50 feet long.
Stipe Stem-like part of seaweed
Submersible A specially built vehicle designed to
submerge underneath the surface of water, usually
for reserach or pleasure.
Vertebrate Animals that have backbones
Zooplankton Microscopic animals that float in the
ocean. They play a vital role in the aquatic food web.