V

Vegetarian: Eating only plants (see herbivore).

Vegetation: plants.

Venom: Poisonous chemical excreted by animals or plants.

Venomous: Characteristic of an animal that produces venom.

Ventral: The lower or under surface of animals.

Vertebrate: An animal with a backbone. Fishes and people are both vertebrates.

Vertical: Up-and-down; in the up-and-down direction (opposite of horizontal).

Vertical migration: An aquatic animal's daily or seasonal movement up toward the water's surface and back down to deeper water.

Vestigial: Nonfunctioning, a remnant of a body part that existed in a former species of an animal. Whales have tiny, vestigial hind legs buried deep in their bodies.

Viscosity: The ability of a liquid to resist the movement of an object (internal resistance of the liquid), caused by molecular attraction within the liquid.

Volcano limpet: A large limpet with a volcano-shaped shell; it prefers warm waters.

Volcanoes: Places where magma from deep in the Earth breaks to surface. Steep-sided volcanoes occur at places where ocean plates collide. Flat volcanoes are found on plates that move slowly over hot spots.