BIO 100 - Chapter 18 UPDATED ACTUAL
Exam Questions and CORRECT Answers
Animals - CORRECT ANSWER - eukaryotic, multicellular, heterotrophic organisms that
obtain nutrients by eating
blastula - CORRECT ANSWER - an early embryonic stage; usually a hollow ball of cells
gastrula - CORRECT ANSWER - one side of the blastula folds inward
larva - CORRECT ANSWER - an immature individual that looks different from the adult
animal
metamorphosis - CORRECT ANSWER - a larva undergoes a major change of body form;
in becoming an adult capable of reproducing sexually
radial symmetry - CORRECT ANSWER - identical all around a central axis
bilateral symmetry - CORRECT ANSWER - there's only one way to split into two equal
halves -right down the midline
body cavity - CORRECT ANSWER - a fluid-filled space separating the digestive tract
from the outer body wall
pseudocoelom - CORRECT ANSWER - if the body cavity is not completely lined by
tissue derived from mesoderm
coelom - CORRECT ANSWER - the type of body cavity humans and many other animals
have, is completely lined by tissue derived from mesoderm
, invertebrates - CORRECT ANSWER - animals without backbones
sponges - CORRECT ANSWER - stationary animals that appear so sedate that the ancient
Greeks believed them to be plants
Cnidarians - CORRECT ANSWER - are characterized by the presence of body tissues as
well as by radial symmetry and tentacles with stinging cells
gastrovascular cavity - CORRECT ANSWER - the basic body plan of a cnidarian is a sac
with a central digestive compartment
polyp - CORRECT ANSWER - adhere to larger objects and extend their tentacles, waiting
for prey
medusa - CORRECT ANSWER - a flattened, mouth-down version of the polyp
Molluscs - CORRECT ANSWER - soft-bodied animals, but most are protected by a hard
shell (snails and slugs, oysters and clams, and octopuses)
radula - CORRECT ANSWER - mollucs use this file-like organ to feed. They scrape up
food
How many body parts do molluscs have? - CORRECT ANSWER - Three; a muscular
foot; a visceral mass containing most of the internal organs; a fold of tissue called the mantle
mantle - CORRECT ANSWER - drapes over the visceral mass and secretes the shell if one
is present
What are the three major groups of molluscs? - CORRECT ANSWER - gastropods;
bivalves; cephalopods
Exam Questions and CORRECT Answers
Animals - CORRECT ANSWER - eukaryotic, multicellular, heterotrophic organisms that
obtain nutrients by eating
blastula - CORRECT ANSWER - an early embryonic stage; usually a hollow ball of cells
gastrula - CORRECT ANSWER - one side of the blastula folds inward
larva - CORRECT ANSWER - an immature individual that looks different from the adult
animal
metamorphosis - CORRECT ANSWER - a larva undergoes a major change of body form;
in becoming an adult capable of reproducing sexually
radial symmetry - CORRECT ANSWER - identical all around a central axis
bilateral symmetry - CORRECT ANSWER - there's only one way to split into two equal
halves -right down the midline
body cavity - CORRECT ANSWER - a fluid-filled space separating the digestive tract
from the outer body wall
pseudocoelom - CORRECT ANSWER - if the body cavity is not completely lined by
tissue derived from mesoderm
coelom - CORRECT ANSWER - the type of body cavity humans and many other animals
have, is completely lined by tissue derived from mesoderm
, invertebrates - CORRECT ANSWER - animals without backbones
sponges - CORRECT ANSWER - stationary animals that appear so sedate that the ancient
Greeks believed them to be plants
Cnidarians - CORRECT ANSWER - are characterized by the presence of body tissues as
well as by radial symmetry and tentacles with stinging cells
gastrovascular cavity - CORRECT ANSWER - the basic body plan of a cnidarian is a sac
with a central digestive compartment
polyp - CORRECT ANSWER - adhere to larger objects and extend their tentacles, waiting
for prey
medusa - CORRECT ANSWER - a flattened, mouth-down version of the polyp
Molluscs - CORRECT ANSWER - soft-bodied animals, but most are protected by a hard
shell (snails and slugs, oysters and clams, and octopuses)
radula - CORRECT ANSWER - mollucs use this file-like organ to feed. They scrape up
food
How many body parts do molluscs have? - CORRECT ANSWER - Three; a muscular
foot; a visceral mass containing most of the internal organs; a fold of tissue called the mantle
mantle - CORRECT ANSWER - drapes over the visceral mass and secretes the shell if one
is present
What are the three major groups of molluscs? - CORRECT ANSWER - gastropods;
bivalves; cephalopods
