Glossary P...

Pack ice: Ice made from sea water.

Paddles: Instrument used to propel a canoe forward.

Parameters: Variable qualities of the environment, e.g. light, temperature, dissolved oxygen.

Palp: Another word for oral-arm.

Parasite: An organism which lives off other organisms.

Parasitism: A symbiotic association in which one organism (the parasite) derives nourishment as it eats the blood or tissue of another (the host), usually without killing the host.

Parts per million (ppm): Measure of concentration of levels of oxygen or nutrients in water samples.

Pebbles: In environmental education, non-confrontational, simple sayings that draw attention to controversial issues.

Pectoral: To do with the shoulder; in fish, the pectoral fins are those at the sides behind the operculum.

Pelagic: Open ocean, as in pelagic plants and animals that live away from the ocean floor. Pelagic sediments are those that fall to the seabed from the waters above.

Pelvic: At the hips. The pair of fins at the back of a fish's body are called pelvic fins.

Penis : The male reproductive organ used to pass sperm into the female.

Perch: A name for a fish with a rounded body; the common name of "perch" is given to many different and unrelated species of fish around the world.

Perishable materials: Materials that deteoriate quickly in air or water, e.g. eggs, apples.

Pesticides: Chemicals used to kill pests on plant crops.

Petrochemicals: A chemical made from petroleum.

pH: A measurement of how much acid is in a substance.

Phosphorous: Chemical used in cleaning products which, released into the environment, stimulates algae to grow.

Photic zone: The zone of the ocean into which light penetrates. The upper sunlit ocean layers to 350 feet deep (195meters), also called the epipelagic zone.

Photophore: A body organ that makes light.

Photosynthesis: The process by which green plants use energy from sunlight to produce sugar and oxygen from carbon dioxide and water. The plants capture the sun's energy with the green chemical chlorophyll.

Phyla: Plural of phylum, the basic subdivision of the animal kingdom. There are 25 of these groups.

Phylum: In biology, a category that's part of the scientific system for grouping together related plants, animals and other organisms (kingdom, phylum, class, order, family, genus, species). Phylum is the category that ranks below a kingdom and above a class.

Phytoplankton: Tiny, floating plants and other kinds of microscopic green organisms that drift with ocean currents and use the sun's energy to make food.

Pickle-weed: A small terrestrial plant that lives close to the sea; it can grow in salty soil that would kill most other land plants.

Pilings: Long, heavy timbers or beams that support a wharf or bridge.

Pinniped: A member of the group of sea mammals that includes seals, sea lions and walruses.

Pipefishes: A group of small, slender fishes, related to sea horses.

Planktivore: An animal that eats plankton.

Plankton: Plants and animals (mostly tiny) that swim weakly, or not at all, and drift with ocean currents. Plankton are an important food source for many organisms that live in the sea.

Plate: In geology, a big piece of the earth's crust. The earth's crust is broken into many plates, which move very slowly as they float on molten rock deep below. Where plates meet, they bump and jostle, giving rise to earthquakes. When one plate is pushed beneath another, mountains, trenches and volcanoes form.

Plimsoll line: A line placed on the hull of ships showing the maximum depth to which they can submerge when they are loaded.

Plumage: The feathers of a bird.

Pneumatophores: Breathing roots of mangroves.

Pod: A pod of marine mammals is a group of animals travelling together.

Pollock: A fish related to cod, heavily fished by people for food. Pollock are made into fish sticks and imitation crab meat.

Pollution: The introduction of substances by humans into the marine environment which results or is likely to result in deleterious effects that harm living resources and marine life.

Polyculture: Multiple cropping of aquacultured animals.

Polyp: A young jelly that results from the joining of sperm and egg; a polyp attaches to a surface and produces identical copies of itself or ephyra.

Polyp: Any sea animal with a fleshy stalk and a crown of tentacles; coral animals are polyps and so are sea anemones.

Pop-rivet: Small metal plug used with pop-rivet gun to secure two sheets of metal together.

Porpoise: A member of a group of small whales that have spade-shaped teeth and rounded snouts.

Port: The left side of a boat, as seen from aboard facing the bow.

Prawn: A shrimp or shrimp like crustacean.

Precipitation: The depositing of water onto the Earth's surface as a solid (snow and hail) or liquid (rain and dew).

Predator: An animal which hunts to catch food.

Preen: To groom and arrange feathers. A bird preens its feathers to keep them clean and in good working order.

Prey: An animal that is killed and eaten by a predator.

Pressure: Term used to describe the speed at which air particles affect the walls of a container. Increase the speed and you increase the pressure.

Pressure air cells: Moving air cells above the Earth's surface which create wind.

Primary dune: First dune to be found as you walk up the beach towards the dune system.

Primer bulb: Rubber bulb used to move fuel from tank to engine when starting.

Process: A series of actions that bring about a result. Scientific process involves making observations, formulating hypotheses, designing and conducting experiments, collecting data, analysing results, drawing conclusions and sharing findings with others.

Producers: Life forms (plants, diatoms, some bacteria) that produce their own food from simple, non-living chemicals. Producers are the basis of all food chains.

Protein: A large group of organic compounds that most organisms use in the construction of their bodies. Muscle, skin and many other kinds of living tissue are made at least partly of protein. Many animals need protein in their diet.

Propeller: Part of powered vessel used to propel a ship forward or in reverse. Device with a revolving hub and a radiating blade.

Puffer fishes: A family of small fishes that puff into a ball when threatened.

Pulse: Regular throbbing of the arteries caused by the beating of the heart. Can be felt in throat or wrist.

Purse seine: A type of fishing net used to surround and catch large schools of fish. The net pulls shut at the top and bottom and looks like a bag or purse.