Phylum Cnidaria

Question 1

Protostome or Deuterostome

Answer 1

Protostome

Question 2

Trip or Dip

Answer 2

diploblastic

• ectoderm → epidermis (outer covering)
• mesoglea – connect epidermis & gastrodermis
• endoderm → gastrodermis (inner lining)

Question 3

Digestion

Answer 3

• incomplete digestive tract
  
  • lack anus
  • lack series of specialized digestive organs
• food → gastrovascular cavity (lined w/ gastrodermis): has to do every step of digestion
• can’t eat more if already full
• undigested food comes out of mouth

Question 4

Respiration

Answer 4

• no specialized respiratory organs
• instead, do cutaneous respiration – does across epidermis, not all cells do own respiration

Question 5

Excretion

Answer 5

• No specialized excretory organs
  
  • but do diffusion w/ environmen

Question 6

Skeleton

Answer 6

• hydrostatic skeleton
• use gastrovascular cavity as hydrostatic skeleton

Question 7

Symmetry?

Answer 7

radial symmetry (undisputed)

Question 8

Level of Organization

Answer 8

tissue level of body organization (no organs)

Question 9

Nervous

Answer 9

Nerve network – diffuse nerve network across entire body that allows it to coordinate movement

Question 10

They have Cnidocytes

What are they?

Answer 10

• Def: cells that can sting
• cells that contain nematocyst
• triggered by cnidocil
• for defense & offense (to obtain fuel)

Question 11

Reproduction?

Answer 11

Either Sexual or asexual (budding, fragmentation) reproduction

Question 12

Colonial or solitary?

Answer 12

Both

Question 13

Common mutualism w/ who?

Answer 13

• common mutualism w/ zooxanthella
• the zooxanthella are a different color & affects the anenomes

Question 14

Body Forms:

1. Polyp

Answer 14

• sedentary
• tentacles “up”
• little mesoglea

Question 15

Body Forms:

2. Medusa

Answer 15

• motile
• tentacles “down”
• large mesoglea

Question 16

Class Hydrozoa

Answer 16

• motile, asexual(budding) & asexual

Question 17

Class Anthozoa (look at slide)

Answer 17

• sea anenomes, corals (lots of colonies)
• septal filament – increase surface area for absorption of nutrients
• coral – secretes calcium carbonate shell for protection
• most don’t eat, but depend on a photosynthetic symbiont
• Reef front – some have resistance, deeper are more adapted for sea light
• Reef flat – adapted for different salinity
• → resource partitioning

Question 18

Class Anthozoa

Resource Partitioning

Answer 18

Question 19

Class Scyphozoa

(life cycle)

Answer 19