Exam 3 Phylum Porifera, Cnideria, Platyhelminthes, Molluska, Annelida

Question 1

Porifera cell types

Answer 1

Epidermis – outer layer
of cells
• Choanocytes – cells
that create current,
catch food
• Amoebocytes – move
through the gelatinous
middle layer, carry
nutrients

Question 2

Cnidarians

Answer 2

Jellies, corals, anemones, hydras

Question 3

Cnidaria symmetry

Answer 3

Radial symmetry
Mouth anus center of body

Question 4

Cnidaria tissue

Answer 4

Diploblastic
• Ectoderm becomes epidermis
• Endoderm becomes gastrodermis

Question 5

phylum Platyhelminthes

Answer 5

Flatworms

planarians, tapeworms
• Flattened dorso-ventrally (top to bottom)
• No circulatory system
• No respiratory system
• Gas exchange, waste elimination, nutrient
movement from GVC to cells by diffusion

Question 6

Class Bivalvia (bivalves)

Answer 6

clams, oysters, mussels, scallops
• All aquatic
• Hinged shell divided into to lateral halves

Question 7

Class Bivalvia (bivalves)

Answer 7

clams, oysters, mussels, scallops
• All aquatic
• Hinged shell divided into to lateral halves

Question 8

Class Cephalopods

Answer 8

octopi, squid, chambered nautilus, cuttlefish
Active marine predators
Grasp prey with suckers on tentacles, bite, inject with poison

Question 9

Siphon

Answer 9

Shoot water out for locomotion

Question 10

Phylum annelida

Answer 10

Segmented worms

Marine, freshwater, soil
Examples: polycheates, leeches, earthworms

Question 11

Symmetry

Answer 11

Asymmetrical – Phylum Porifera
Radial Symmetry – Phylum Cnidaria
Bilateral Symmetry – everything else

Question 12

Digestion

Answer 12

Intracellular – Phylum Porifera
GVC - Cnidaria, Planarians
no digestion - tapeworms
complete digestive tract – everything else