Chapter 32

Question 1

Animals are ____________that ingest their food

Answer 1

heterotrophs

Question 2

All animals can trace their lineage to a common ancestor that lived in the _____

Answer 2

Neoproterozoic era

Question 3

Which of the following is (are) unique to animals?

Answer 3

nervous conduction and muscular movement

Question 4

Animal cells are held together by structural proteins such as___________

Answer 4

collagen

Question 5

________ are groups of cells that have a common structure, function, or both

Answer 5

Tissues

Question 6

Most animals reproduce sexually, with the _______ stage usually dominating the life cycle

Answer 6

diploid

Question 7

Cleavage leads to formation of a multicellular, hollow _________

Answer 7

blastula

Question 8

The blastula undergoes __________, forming a ________ with different layers of embryonic tissues

Answer 8

gastrulation, gastrula

Question 9

A ______ is sexually immature and morphologically distinct from the adult; it eventually undergoes ___________

Answer 9

larva, metamorphosis

Question 10

A _________resembles an adult, but is not yet sexually mature

Answer 10

juvenile

Question 11

Most animals, and only animals, have _______ that regulate the development of body form

Answer 11

Hox genes

Question 12

Although the Hox family of genes has been highly conserved, it can produce a wide diversity of ___________

Answer 12

Animal morphology

Question 13

The common ancestor of living animals (675-800 MYA) may have resembled modern _________, protists that are the closest living relatives of animals

Answer 13

choanoflagellates

Question 14

The common ancestor is likely to have been a protist that lived during the _________.

Answer 14

Neoproterozoic

Question 15

Early members of the animal fossil record include the _________, which dates from 565 to 550 million years ago

Answer 15

Ediacaran biota

Question 16

The ____________ (535 to 525 million years ago) marks the earliest fossil appearance of many major groups of living animals

Answer 16

Cambrian explosion

Question 17

The beginning of the_________ era followed mass extinctions of both terrestrial and marine animals. These extinctions included the large, nonflying dinosaurs and the marine reptiles

Answer 17

Cenozoic

Question 18

Zoologists sometimes categorize animals according to a _________, a set of morphological and developmental traits

Answer 18

body plan

Question 19

In some species, such as worms, sea urchins, and vertebrates, the protein ________ marks the site of gastrulation and activates the transcription of genes necessary for the process.

Answer 19

-catenin

Question 20

Some animals have _________, with no front and back, or left and right

Answer 20

radial symmetry

Question 21

Two-sided symmetry is called _________

Answer 21

bilateral symmetry

Question 22

Bilaterally symmetrical animals have
A dorsal (top) side and a ventral (bottom) side
A right and left side
Anterior (head) and posterior (tail) ends
__________, the development of a head

Answer 22

Cephalization

Question 23

Radial animals are often _____or __________

Answer 23

sessile, planktonic

Question 24

________ is the germ layer covering the embryo’s surface

Answer 24

Ectoderm

Question 25

_________ is the innermost germ layer and lines the developing digestive tube, called the archenteron

Answer 25

Endoderm

Question 26

Sponges and a few other groups lack ______

Answer 26

true tissues

Question 27

________animals have ectoderm and endoderm | These include cnidarians and comb jellies

Answer 27

Diploblastic

Question 28

_______ animals also have an intervening ______ layer (develops into the lining of the coelom, muscles, skeleton, gonads, kidneys and circulatory system); these include all bilaterians

Answer 28

Triploblastic, mesoderm

Question 29

Most triploblastic animals possess a _______

Answer 29

body cavity

Question 30

A true body cavity is called a ________ and is derived from mesoderm

Answer 30

coelom

Question 31

________ are animals that possess a true coelom

Answer 31

Coelomates

Question 32

A ________ is a body cavity derived from the mesoderm and endoderm

Answer 32

pseudocoelom

Question 33

Triploblastic animals that possess a pseudocoelom are called ___________

Answer 33

pseudocoelomates

Question 34

Triploblastic animals that lack a body cavity are called _________

Answer 34

acoelomates

Question 35

_________ is a clade of animals with true tissues

Answer 35

Eumetazoa

Question 36

Most animal phyla belong to the clade ________ and are called __________

Answer 36

Bilateria, Bilaterians

Question 37

What distinguishes a coelomate animal from a pseudocoelomate animal is that coelomates

Answer 37

a body cavity completely lined by mesodermal tissue, whereas pseudocoelomates do not.

Question 38

The morphology-based tree divides bilaterians into two clades _______ and _________

Answer 38

deuterostomes, Protostomes

Question 39

Ecdysozoans shed their exoskeletons through a process called _____. Example Cicada.

Answer 39

ecdysis

Question 40

There are several hypotheses regarding the cause of the cambrian explosion and decline of Edicaran Biota

Answer 40

- New Predator-prey relationship - A rise in atmospheric oxygen - The evoulution of the HOX gene Complex