Definition: In unequal cleavage, the first two cell divisions are unequal producing four cells in which one cell is bigger than the other three. This larger cell is specified as the D macromere.
Definition: A landform consisting of loose rock particles such as sand, gravel, shingle, pebbles, cobble, or even shell fragments along the shoreline of a body of water.
Definition: The marine benthic biome (benthic meaning 'bottom') encompasses the seafloor and includes such areas as shores, littoral or intertidal areas, marine coral reefs, and the deep seabed.
Definition: A wavelike sequence of muscular contraction and relaxation that passes along a tubelike structure, such as a vertebrate intestine, or the body of an earthworm
Definition: Capable of creating a new organism by combining the genetic material of two gametes, which may come from two parent organisms or from a single organism, in the case of self-fertilizing hermaphrodites.
Definition: A structural quality inhering in a bearer by virtue of the bearer's being thicker or more closely packed together; pressed tightly together.
Definition: Museum für Naturkunde Berlin (Zoological Collections) (ZMB). Berlin, Germany. URL for main institutional website: http://www.naturkundemuseum-berlin.de Formerly Zoologisches Museum der Humboldt-Universität zu Berlin
