Unit 2: Animals

Question 1

What are the four characteristics seen in animals?

Answer 1

• Eat other animals to obtain nutrients
• Animals are motile in at least one stage of their life
• Pass through common stages during development from embryo
• Almost all animals have specialized tissue

Question 2

From which colony of protists did the first animal evolve?

Answer 2

Flagellate protists

Question 3

What is the Cambrian explosion?

Answer 3

Many different animal body plans appear in the fossils

Question 4

What are two hypotheses for the Cambrian explosion?

Answer 4

• Hard body coverings led to increasingly complex predator-prey relationships
• Atmospheric oxygen reached high enough concentration to support the metabolism of more active, mobile animals

Question 5

What are Hox genes?

Answer 5

Genes that control cells during development and cause different body plans

Question 6

What are the different ways animals reproduce?

Answer 6

• Sexual reproduction (fertilization of gametes)
• Asexual reproduction (budding/fragmentation)
• Parthenogenesis (unfertilized eggs develop into new offspring)

Question 7

List the eight features observed when dividing animals.

Answer 7

• Cell and tissue organization
• Body symmetry
• Germ layers
• Protostomes or deuterostomes
• Ecdysozoans or lophotrochozoans
• Body cavity
• Digestive tract
• Segmentation

Question 8

What are the three different types of symmetry?

Answer 8

• Radial (multiple parts around a central axis)
• Bilateral (only one plane can divide animal into mirror images)
• Asymmetrical (lack symmetry)

Question 9

What is the difference between deuterostomes and protostomes?

Answer 9

• Deuterostomes: first opening is the anus, develops back to front
• Protostomes: first opening is the mouth, develops front to back

Question 10

Define acoelomate.

Answer 10

Lack coelom (no true body cavity)

Question 11

Define pseudocoelomate.

Answer 11

Incomplete body cavity (mesoderm only lines epidermis - body wall)

Question 12

Define coelomate.

Answer 12

True body cavity - organs are encased within the mesoderm

Question 13

What are the four chordate characteristics?

Answer 13

• Notochord
• Dorsal hollow nerve cord
• Postanal tail
• Pharyngeal pouches

Question 14

List evolutionary innovations as vertebrates moved from water to land.

Answer 14

• Denser bones
• Lungs and circulatory system
• Acute hearing and sight, tear glands, and eyelids

Question 15

What is a monotreme?

Answer 15

Lay eggs

Question 16

Give examples of monotremes.

Answer 16

• Echidnas
• Platypuses

Question 17

What is a marsupial?

Answer 17

Give birth to underdeveloped offspring; development is finished within a pouch

Question 18

Give examples of marsupials.

Answer 18

• Kangaroos
• Koalas
• Opossums

Question 19

What is a placental mammal?

Answer 19

Give birth to completely developed offspring

Question 20

Give examples of placental mammals.

Answer 20

• Polar bears
• Dogs
• Horses

Question 21

Which phylum contains vertebrates with deuterostome development?

Answer 21

Chordata

Question 22

Which phylum contains animals that have nerve nets?

Answer 22

Cnidaria

Question 23

Which phylum contains cuttlefish?

Answer 23

Mollusca

Question 24

Which phylum contains animals that have a radula?

Answer 24

Mollusca

Question 25

Which phylum contains roundworms?

Answer 25

Nematoda

Question 26

Which phylum contains animals that have a closed circulatory system and nephridia?

Answer 26

Annelida

Question 27

Which phylum contains animals that have an open circulatory system and nephridia?

Answer 27

Mollusca

Question 28

Which phylum contains animals that use choanocytes to filter food?

Answer 28

Porifera

Question 29

Which phylum contains animals that use the water vascular system?

Answer 29

Echinodermata

Question 30

Which phylum contains animals that are bilateral and acoelomate?

Answer 30

Platyhelminthes

Question 31

Which phylum contains sponges?

Answer 31

Porifera

Question 32

Which phylum contains animals that must molt their cuticle to grow?

Answer 32

Nematoda

Question 33

Which phylum contains certain members that have book lungs?

Answer 33

Arthropoda

Question 34

Which phylum contains leeches?

Answer 34

Annelida

Question 35

Which phylum contains members that reproduce by spawning?

Answer 35

Echinodermata

Question 36

Which phylum contains animals whose body is supported by a mesohyl?

Answer 36

Cnidaria

Question 37

Which phylum contains animals that use penis fencing?

Answer 37

Platyhelminthes

Question 38

Which phylum contains animals that have a coelom ONLY around the heart?

Answer 38

Mollusca

Question 39

Which phylum contains dogs?

Answer 39

Chordata

Question 40

Which phylum contains animals that have a tissue level of organization?

Answer 40

Cnidaria

Question 41

Which phylum contains animals with an exoskeleton made of chitin?

Answer 41

Arthropoda

Question 42

Which phylum contains pseudocoelomates?

Answer 42

Nematoda

Question 43

Which phylum contains sea cucumbers?

Answer 43

Echinodermata

Question 44

Which phylum showed cephalization FIRST?

Answer 44

Platyhelminthes (flatworms)

Question 45

Which phylum contains bilateral larva and radial adult?

Answer 45

Echinodermata

Question 46

Which phylum contains butterflies?

Answer 46

Arthropoda

Question 47

Which phylum contains animals that have a complete digestive system with specialized mouthparts?

Answer 47

Arthropoda

Question 48

Which phylum contains animals that use renette cells?

Answer 48

Nematoda

Question 49

Which phylum contains flatworms?

Answer 49

Platyhelminthes

Question 50

Which phylum uses a hydrostatic skeleton for support?

Answer 50

Annelida

Question 51

Which phylum contains corals?

Answer 51

Cnidaria

Question 52

Which phylum contains asymmetrical animals?

Answer 52

Porifera

Question 53

Which phylum showed a circulatory system FIRST?

Answer 53

Mollusca

Question 54

Which phylum contains members that have three germ layers and a backbone?

Answer 54

Chordata

Question 55

Which phylum contains snails?

Answer 55

Mollusca

Question 56

Which subphylum shows the four chordate characteristics in larval form ONLY?

Answer 56

Urochordata

Question 57

Which class includes chickens?

Answer 57

Aves

Question 58

Which class contains members covered in scales made of keratin?

Answer 58

Reptilia

Question 59

Which class contains animals that have skeletons made of cartilage?

Answer 59

Chondrichthyes

Question 60

Which class includes polar bears?

Answer 60

Mammalia

Question 61

Which class includes jawless fishes?

Answer 61

Agnatha

Question 62

Which subphylum includes lancelets?

Answer 62

Cephalochordata

Question 63

Which class contains members that have swim bladders?

Answer 63

Osteichthyes

Question 64

Which class was the FIRST to colonize land?

Answer 64

Amphibia

Question 65

Which class was the first to use amniotic eggs?

Answer 65

Reptilia

Question 66

Which class can live in areas that are scarce in food due to being ectotherms?

Answer 66

Reptilia

Question 67

Which class includes sting rays?

Answer 67

Chondrichthyes

Question 68

Which class contains animals that have bones that are hollow?

Answer 68

Aves

Question 69

Which class includes lizards?

Answer 69

Reptilia

Question 70

Which subphylum includes tunicates?

Answer 70

Urochordata

Question 71

Which class contains members that were the first to show cranium?

Answer 71

Agnatha

Question 72

Which class contains animals that are endothermic and have no teeth?

Answer 72

Aves

Question 73

Which class includes clown fish?

Answer 73

Osteichthyes

Question 74

Which class contains animals that have a lateral line to detect vibrations?

Answer 74

Chondrichthyes

Question 75

Which class has a structure that secretes milk?

Answer 75

Mammalia

Question 76

Which subphylum shows the four chordate characteristics as adults ONLY?

Answer 76

Osteichthyes

Question 77

Which class contains animals that have operculum?

Answer 77

Osteichthyes

Question 78

Which class includes salamanders?

Answer 78

Amphibia