Lecture 5

Question 1

what are the body forms of cnidaria

Answer 1

• polyp
• medusa

Question 2

what kind of symmetry do cnidarians have

Answer 2

radial symmetry

Question 3

what kind of cavity do cnidarians have

Answer 3

gastrovascular cavity

Question 4

the gastrovascular cavity of cnidarians has how many openings

Answer 4

one

Question 5

what is the opening of the gastrovascular cavity of cnidarians surrounded by

Answer 5

tentacles

Question 6

what are cnidocytes on cnidarians

Answer 6

structures for stinging

Question 7

what are cnidae

Question 8

if i say cnidarians are dimorphic - what does this means

Answer 8

two possible body forms in the phylum

Question 9

what are the key characteristics of the polyp morph of cnidarians

Answer 9

• attatched to a surface
• mouth/anus at the top

Question 10

what are the key characteristics of the medusa morph of cnidarians

Answer 10

• free floating
• mouth/anus at the bottom

Question 11

what are the subclasses of cnidarians

Answer 11

• anthozoa
• staurozoa
• scyphozoa
• cubozoa
• hydrozoa

Question 12

what forms can anthozoans be

Answer 12

polyp form only

Question 13

what forms can staurozoans be

Answer 13

polyp form only

Question 14

what forms can scyphozoans be

Answer 14

medusa and only sometimes polyp

Question 15

what forms can cubozoans be

Answer 15

medusa and only sometimes polyp

Question 16

what forms can hydrozoans be

Answer 16

both medusa or polyp

Question 17

what lifestyle do anthozoans lead?

Answer 17

solitary or colonial

Question 18

what lifestyle do staurozoans lead?

Answer 18

solitary

Question 19

what lifestyle do scyphozoans lead?

Answer 19

solitary

Question 20

what lifestyle do cubozoans lead?

Answer 20

solitary

Question 21

what lifestyle do hydrozoans lead?

Answer 21

solitary or colonial

Question 22

what are the structural characteristics of a hydrozoan

Question 23

what are the structural characteristics of a scyphozoan

Question 24

what are the structural characteristics of a cubozoan

Question 25

what class are sea anemones

Answer 25

anthozoa

Question 26

what are the structural characteristics of a sea anemone

Question 27

what class are corals

Answer 27

anthozoa

Question 28

what are the structural characteristics of a coral

Question 29

what are zooids

Answer 29

individual animals in a colony

Question 30

what are the types of zooids in colonial cnidarians

Answer 30

- gastrozooid - dactylozooid - gonozooid

Question 31

what is a gastrozooid in cnidarians

Answer 31

feeding polyps with mouth and tentacles for prey capture

Question 32

what is a dactylozooid in cnidarians

Answer 32

defense polyps with tentacles but no mouth

Question 33

what is gonozooid in cnidarians

Answer 33

reproductive zooids with no mouth (male or female)

Question 34

what are nematocysts

Question 35

what kind of nervous system do cnidarians have

Answer 35

a nerve net

Question 36

where is the nerve net of cnidarians found

Answer 36

at the base of the epidermis and at the base of the gastrodermis (two interconnected nets)

Question 37

what is the directionality of nerve impulses in nerve nets of cnidarians

Answer 37

bidirectional

Question 38

in cnidarians, nerve processes synapse with what kinds of cells

Answer 38

- neurosensory cells - epitheliomuscular cells - nutritive muscular cells

Question 39

what are myofibrils in cnidarians

Question 40

what does the name ctenophora mean?

Answer 40

comb bearing

Question 40

what are ctenes

Answer 40

comb like plates on ctenophores

Question 40

in cnidarians, contraction of lateral myofibrils permits what kind of movement

Answer 40

peristalic type circle gets smaller

Question 41

in cnidarians, contraction of longitudinal myofibrils permits what kind of movement

Answer 41

shortening length gets shorter

Question 42

how many rows of ctenes do ctenophores have

Answer 42

eight

Question 42

what kind of symmetry do ctenophores have

Answer 42

radial symmetry

Question 42

what level of organization do ctenophores have

Answer 42

tissue level

Question 42

how do ctenophores move

Answer 42

- ctenes beat in unison - start at aboral end, progress to oral end, propels animal

Question 43

what is the lifestyle of ctenophores

Answer 43

free swimming prefers warm surface water

Question 43

what kind of "blastic" are ctenophores

Answer 43

diploblastic

Question 44

what is the nervous system of a ctenophore

Answer 44

- a nerve net - have a statocyst

Question 45

what is a statocyst in ctenophores

Answer 45

- a sense organ - allows for orientaion