Exam 2 Vocab 3 Flashcards
Endoparasite
a parasite that lives inside the host’s body
Ganglion
a mass of neurons in a centralized nervous system
Hydrostatic skeleton
a system of body support involving a body wall in tension surrounding a fluid or soft tissue under compression
Lophotrochozoans
a major lineage of protostomes (lophotrochozoa) that grow by extending the size of their skeletons rather than by molting. Many phyla have a specialized feeding structure (lophophore) and/or ciliated larvae (trochophore). Includes rotifers, flatworms, segmented worms, and mollusks.
Mass feeder
animal that ingest chunks of food
Mesoderm
the middle of the three basic cell layers in most animal embryos; gives rise to muscles, bones, blood, and some internal organs (kidney, spleen, etc.)
Nerve net
a nervous system in which neurons are diffuse instead of being clustered into large ganglia or tracts; found in cnidarians and ctenophores
Protostomes
a major lineage of animals that share a pattern of embryological development, including formation of the mouth earlier than the anus, and formation of the coelom by splitting of a block of mesoderm. Includes arthropods, mollusks and annelids
pseudocoelomate
an animal that have a coelom that is only partially lined with mesoderm
Radial symmetry
an animal body pattern that has at least two planes of symmetry. Typically, the body is in the form of a cylinder or disk, and the body parts radiate from a central hub
Oviparous
in animals, producing eggs that are laid outside the body where they develop and hatch
ovoviviparous
in animals, producing eggs that are retained inside the body until they are ready to hatch
Viviparous
producing live young (instead of eggs) that develop within the body of the mother before birth
Medusa
the free-floating stage in the life cycle of some cnidarians
polyp
the immotile (sessile) stage in the life cycle of some cnidarians
