A relationship between two species in which one, called the parasite, benefits from the association while the other, called the host, is negatively affected.

parasitisme

Living in the open water, away from the shore and the sea bottom.

pélagique

A flattened, transparent planktonic larva of spiny lobsters that drifts in the water column before metamorphosing into a young lobster.

phyllosome

Microscopic, photosynthetic organisms that drift in water and form the base of aquatic food chains.

phytoplancton

A flat, thin cell that forms the outer layer of a sponge, providing protection and structural support.

pinacocyte

Describes a species whose embryos develop in the female's uterus and receive nutrients through a structure that functions as a placenta.

placentaire

Tiny organisms that drift in water currents, including both plants (phytoplankton) and animals (zooplankton).

plancton

Living in open water and mainly drifting with the currents.

planctonique

Free-swimming larvae of many corals and other cnidarians that drift in the water before settling on a suitable surface to continue their development.

planulas

A tubular cell in sponges that forms a pore, allowing water to flow into the sponge's body.

porocyte

An individual organism that starts life as a male and later may change to a female.

protandre

A form of sequential hermaphroditism in which an organism starts life as a male and later changes to a female.

protérandrie

An individual organism that starts life as a female and later may change to a male.

protogyne

A form of sequential hermaphroditism in which an organism starts life as a female and later changes to a male.

protogynie

A simple, primarily microscopic, plant-like organism, such as algae or bacteria, that performs photosynthesis or other basic life processes.

protophyte

A single-celled, microscopic organism that can move independently and often feeds on organic matter.

protozoaire

Pear-shaped, generally wider at one end and narrower at the other.

piriforme