Chapter 32: Animal Diversity

Question 1

Describe how animals are different from plants and fungi regarding nutrition

Answer 1

animals ingest/consume their food, whereas plants create their food and fungi feed by absorption

Question 2

describe how animals are different from plants and fungi regarding cell structure & specialization

Answer 2

animals lack the structural support of cell walls, and instead use a protein, such as collagen, which is not found in plants or fungi. Animals cells are also organized into tissues.

Question 3

describe how animals are different from plants and fungi regarding reproduction and development

Answer 3

most animals reproduce sexually, and diploid stage dominates the life cycle. unlike plants and fungi, haploid sperm and egg are produced directly from meiotic division

Question 4

a hollow ball of cells that marks the end of the cleavage stage during early embryonic development in animals

Answer 4

blastula

Question 5

in animal development, a series of cell and tissue movements in which the blastula-stage embryo folds inward, producing a 3-layered embryo, the gastrula

Answer 5

gastrulation

Question 6

What are the closest living relatives of animals?

Answer 6

choanoflagellates

Question 7

the first generally accepted macroscopic fossils date from about ___ million years ago

Answer 7

560 million years ago

Question 8

the first generally accepted macroscopic fossils are members of an early group of soft-bodied multi-cellular eukaryotes known as

Answer 8

Ediacaran biota - a time of increasing animal diversity

Question 9

another wave of animal diversification occurred 535-525 million years ago, during the Paleozoic era

Answer 9

the Cambrian explosion

Question 10

• most fossils from the Cambrian explosion

- an enormous clade whose members have a two-sided or bilaterally symmetric form and a complete digestive tract

Answer 10

bilaterians

Question 11

• era 251-65.5 million years ago
• evolved animal phyla from Paleozoic now began to spread to new habitats
• flowering plants and insects underwent dramatic diversifications late in this era

Answer 11

Mesozoic era

Question 12

• 65.5 million years ago
• mass extinctions of terrestrial and marine animals started this era (ex dinosaur extinction)
• global climate cooled

Answer 12

Cenozoic era

Question 13

particular set of morphological and developmental traits, integrated into a functional whole - the living animal

Answer 13

body plan

Question 14

give an example of something that has radial symmetry

Answer 14

flower pot, sea anemone

Question 15

give an example of something that has bilateral symmetry

Answer 15

shovel, lobster

Question 16

the germ layer covering the surface of the embryo gives rise to the outer covering of the animal and in some phyla, to the central nervous system

Answer 16

ectoderm

Question 17

innermost germ layer that lines the pouch that forms during gastrulation and gives rise to the lining of the digestive tract or cavity

Answer 17

endoderm

Question 18

Cnidarians and a few other animal groups that have only these two germ layers are said to be

Answer 18

diploblastic

Question 19

all bilaterally symmetrical animals have a 3rd layer called the ________ which fills the space between the ectoderm and endoderm

Answer 19

mesoderm

Question 20

all bilaterally symmetrical animals are said to be _______ because of the three layers of germ tissue

Answer 20

triploblastic

Question 21

a fluid or air-filled space located between the digestive tract and the outer body wall, aka coelom

Answer 21

body cavity

Question 22

animals with a true coelom are known as

Answer 22

coelomates

Question 23

some triploblastic animals have a body cavity that is formed from mesoderm and endoderm, and this cavity is called

Answer 23

pseudocoelom

Question 24

animals that have a pseudocoelom are known as

Answer 24

pseudocoelomates

Question 25

some triploblastic animals lack a body cavity all together and those are called

Answer 25

acoelomates

Question 26

in animals, a developmental mode distinguished by the development of the mouth from the blastopore; often also characterized by spiral cleavage and by the body cavity forming when solid masses of mesoderm split

Answer 26

protostome development

Question 27

in animals, a developmental mode distinguished by the development of the anus from the blastospore; often alos characterized by radial cleavage and by the body cavity forming as outpockets of mesodermal tissue

Answer 27

deuterostome development

Question 28

during gastrulation, an embryo’s developing digestive tube initially forms as a blind pouch known as the

Answer 28

archenteron

Question 29

• animals are monophyletic, forming a clade called Metazoa

- all extant and extinct animals share a common ancestor

Answer 29

1) All animals share a common ancestor

Question 30

• sponges, phylum porifera, branch from the base of the animal tree
• sponges are monophyletic

Answer 30

2) Sponges are basal animals

Question 31

• all animals except for sponges belong to eumetazoans

- true tissues evolved in the common ancestor of extant eumetazoans

Answer 31

3) Eumetazoa is a clade of animals with true tissues

Question 32

• this clade contains the majority of animal phyla
• includes animals with bilateral symmetry and 3 prominent germ layers
• cambrian explosion was rapid diversification

Answer 32

4) most animal phyla belong to the clade Bilateria

Question 33

-bilaterians have three main lineages:
deuterostomia, lophotrochozoa, ecdysozoa
-the phyla in these clades consist entirely of invertebrates

Answer 33

5) there are three major clades of bilaterian animals

Question 34

one of the three main lineages of bilaterian animals; includes organisms that have lophophores or trochophore larvae

Answer 34

lophotrochozoa

Question 35

in some lophotrochozoan animals, including brachiopods, a crown of ciliated tentacles that surround the mouth and function in feeding

Answer 35

lophophore

Question 36

larval stage unique to mollusks

Answer 36

veliger

Question 37

free-swimming larval stage surrounded by ring of cilia

Answer 37

trochophore

Question 38

lophophorate animal that resembles a bivalve but posesses a lophophore inside its shell

Answer 38

brachiopod

Question 39

repeated body segments of an animal

Answer 39

metamerism