Chapter 32

Question 1

cephalization

Answer 1

nervous tissue, over many generations, becomes concentrated toward one end of an organism. This process eventually produces a head region with sensory organs.

Question 2

hydrostatic skeleton

Answer 2

The system of support found in soft-bodied invertebrates, which relies on the incompressibility of fluids contained within the body cavity. For example, in earthworms the coelomic fluid is under pressure within the coelom and therefore provides support for internal organs.

Question 3

protostome

Answer 3

Any of a major group of animals defined by its embryonic development, in which the first opening in the embryo becomes the mouth.

Question 4

deuterostome

Answer 4

are distinguished from protostomes by their deuterostomic embryonic development; in deuterostomes, the first opening (the blastopore) becomes the anus

Question 5

Ecdysozoa

Answer 5

is a group of protostome animals, including Arthropoda (insects, chelicerata, crustaceans, and myriapods), nematoda, and several smaller phyla. A clade of moulting animals that encompasses primarily the arthropods and nematodes.

Question 6

Lophotrochozoa

Answer 6

A clade that encompasses the annelids, molluscs, and several other phyla; they are distinguished by two morphological features - the lophophore, a crown of tentacles used for feeding, and the trochophore larva, a distinct larval stage.

Question 7

suspension feeder

Answer 7

an animal that feeds on material (such as planktonic organisms) suspended in water and that usually has various structural modifications for straining out its food.

Question 8

deposit feeder

Answer 8

aquatic animal that feeds on small specks of organic matter that have drifted down through the water and settled on the bottom. Examples of deposit feeders are flounders, eels, haddock, bass, crabs, shellfish, snails and sea cucumbers

Question 9

fluid feeder

Answer 9

organisms that feed on the fluid of other organisms. It can refer to: Hematophagy, feeding on blood. Nectarivore, feeding on nectar. Plant sap feeders.

Question 10

radula

Answer 10

an anatomical structure that is used by molluscs for feeding, sometimes compared to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food enters the esophagus.

Question 11

endoparasite

Answer 11

any of various parasites that live in the internal organs of animals (especially intestinal worms) endozoan, entoparasite, entozoan, entozoon. parasite - an animal or plant that lives in or on a host (another animal or plant); it obtains nourishment from the host without benefiting or killing the host.

Question 12

ectoparasite

Answer 12

a parasite that lives on the outside of its host rather than within the hosts body. Fleas and lice are examples.

Question 13

oviparous

Answer 13

produces eggs that develop outside its body. oviparous. They are oviparous, or egg laying, and have rigid fangs.

Question 14

viviparous

Answer 14

An animal that gives birth to live offspring, as opposed to laying eggs.

Question 15

ovoviviparous

Answer 15

producing eggs that develop within the maternal body and hatch within or immediately after extrusion from the parent

Question 16

holometabolous

Answer 16

Complete, or holometabolous, metamorphosis is characteristic of beetles, butterflies and moths, flies, and wasps. Their life cycle includes four stages: egg, larva ( q.v.), pupa ( q.v.), and adult.

Question 17

hemimetabolous

Answer 17

also called incomplete metamorphosis and paurometabolism, is the mode of development of certain insects that includes three distinct stages: the egg, nymph, and the adult stage, or imago. These groups go through gradual changes; there is no pupal stage.

Question 18

benthic

Answer 18

ecological region at the lowest level of a body of water such as an ocean or a lake, including the sediment surface and some sub-surface layers. Organisms living in this zone are called benthos, e.g. the benthic invertebrate community, including crustaceans and polychaetes.

Question 19

spicule

Answer 19

a small or minute, slender, sharp-pointed body or part; a small, needlelike crystal, process, or the like. Zoology. one of the small, hard, calcareous or siliceous bodies that serve as the skeletal elements of various marine and freshwater invertebrates.