cnidaria

Question 1

types of cnidaria

Answer 1

Jellyfish
Sea anemones
Corals
Myxozoans

Question 2

habitat

Answer 2

Aquatic

Sessile or weakly swimming

Question 3

ecology

Answer 3

Carnivorous predators, some parasites (myxozoans)
Often have symbiotic zooxanthellae/zoochlorellae

Question 4

mutualism in coral: trade-offs

Answer 4

Symbionts give products of photosynthesis and help with skeletal formation
Coral give waste products like CO2 (useful for photosynthesis) and access to light

Question 5

major morphological types of cnidarians

Answer 5

polyps
medusa

Question 6

polyps

Answer 6

Can be single or form colonies
Genetically identical polyps are produced by budding (although I think sexual reproduction is also possible for them?

Question 7

Hydrostatic skeleton

Answer 7

Muscles contract against fluid in an enclosed compartment to bring about movement

Question 8

Supporting skeleton

Answer 8

Only present in some animals
Made of hard or semi-rigid material

Question 9

Layers of the body wall

Answer 9

Epidermis
Mesoglea
Gastrodermis

Question 10

Feeding

Answer 10

Prey immobilized and adhered to tentacle, transferred to digestive cavity, remains regurgitated

Question 11

Cnidae

Answer 11

Discharged from cnidocytes in the epithelium, facilitate prey capture

Question 12

Types of cnidae

Answer 12

Penetrant
Volvent
Adherent

Question 13

Penetrant cnidae

Answer 13

Penetrate prey and inject venom

Question 14

Adherent cnidae

Answer 14

Sticky tubules used for attachment
Assist in attaching prey to cnidarian tentacle

Question 15

Volvent

Answer 15

Whiplike structures that coil around parts of prey and entrap

Question 16

Nervous system

Answer 16

Net-like
No cephalization (formation of head and brain and nervous system centralization

Question 17

Sensory organs

Answer 17

Ocelli
Statocysts

Question 18

Ocelli

Answer 18

Can detect light

Question 19

Statocysts

Answer 19

Detente position in relation to the ground

Question 20

***CNIDARIAN PHYLA

Answer 20

Hydrozoa
Scyphozoa
Cubozoa
Anthozoa

Question 21

Hydrozoan characteristics

Answer 21

Solitary or colonial polyps that also have medusae
Polyps may have a supporting exoskeleton
Hydromedusae are small and may be seasonal

Question 22

Unique hydrozoan qualities (what helps distinguished them)

Answer 22

Epidermal cnidae only
Gastrovascular cavity is a simple sac
Velum present in hydromedusae

Question 23

Hydroid colonies

Answer 23

Repeated budding of CONNECTED polyps
Diverse morphology
All share a Gastrovascular cavity- physiologically interdependent

Question 24

Polyp types

Answer 24

Gastrozooid
Gonozooid
Dactylozooid

Question 25

Gastrozooid

Answer 25

Polyp type specialized for Feeding

Question 26

Gonozooid

Answer 26

Specialized for producing medusae

Question 27

Obelia life cycle

Answer 27

Medusa bud detaches from reproductive polyp, reaches sexual maturity, produces gametes, planula Larva settles, grows and develops into a polyp colony Asexual budding is how individuals within the colony reproduce

Question 28

Morphology of Hydractinia echinata (snail fur)

Answer 28

Feeding tentacles, dactylozooids for defense, developing medusae

Question 29

Cool fact of Turtopsis sp. (immortal jellyfish)

Answer 29

Medusae can revert to polyps - under adverse conditions, adults can turn into a “meatball” which is a young polyp looking for a place to settle down.

Question 30

Life cycle of Aurelia aurita

Answer 30

Adults are gonochoristic Fertilization Development of planula larvae Planula settles, becomes scyphistoma (feeding polyp) Produces identical polyps by budding Polyps grow to be strobila Strobila undergo transverse budding (old are on top, new grow under) Mature strobila pop off and are young adults (ephyra)

Question 31

Regeneration in young Aurelia, old Aurelia

Answer 31

Adults- YES regeneration Young EPHYRA- NO regeneration, YES symmetrization (regaining symmetry after loss of limbs)

Question 32

Portuguese man o’war (physalia physalis) characteristics

Answer 32

Sail using gas filled float Long tentacles Large numbers of nematocysts Prey upon fish

Question 33

Class scyphozoa

Answer 33

Jellyfish All Marine Medusa stage predominates Polyps (scyphistoma) are small and inconspicuous

Question 34

Class cubozoa

Answer 34

Box jellyfish or sea wasps Bell is square in cross section Velarium present, making them relatively fast swimmers Wicked stings Ex: chironex fleckeri

Question 35

Cool features/characteristics of anemones

Answer 35

Acontial filaments Acrorhagi Asexual reproduction via pedal laceration Unusual prey

Question 36

Anthozoa species example

Answer 36

Metridium sp

Question 37

Class Anthozoa characteristics

Answer 37

Polyps only Solitary or colonial Usually produce both sexually and asexually All marine: hard substrates or burrowing

Question 38

Class Anthozoa- general examples

Answer 38

Sea anemones Sea fans Sea whips Sea pens Sea pansies Stony corals

Question 39

what are in the order gorgonacea?

Answer 39

sea fans and sea whips