BIS 2C: Cnidaria

Question 1

What kind of symmetry?

Answer 1

radial symmetry, around a longitudinal axis

Question 2

What kind of gut?

Answer 2

incomplete gut: single opening (serving as mouth and anus) leading to gastrovascular cavity

Question 3

Diploblastic

Answer 3

two layers separated by mesoglea
- ectoderm (epidermis) and endoderm (gastrodermis)

Question 4

two body forms

Answer 4

polyp and medusa

Question 5

polyp

Answer 5

tube shaped, usually sessile with oral end up

Question 6

medusa

Answer 6

bell shaped, motile, oral end facing down

Question 7

cnidocyte

Answer 7

specialized cell with unique stinging or adhesive structure called cnida (most common type: nematocyst)

Question 8

How does the cnida work?

Answer 8

coiled cnida is discharged suddenly with hydrostatic pressure, penetrating prey and injecting poison

Question 9

reproduction in cnidaria

Answer 9

asexual polyp stage and sexual medusa stage

Question 10

sea jellies and hydrozoans

Answer 10

dioecious

Question 11

corals and sea anemones

Answer 11

monoecious or dioecious

Question 12

cube jellies

Answer 12

dioecious

Question 13

feeding

Answer 13

carnivorous, extracellular digestion

Question 14

anthozoa

Answer 14

sea anemone, coral, sea pen

Question 15

cubozoa

Answer 15

cube/ box jelly

Question 16

Hydrozoa

Answer 16

hydra, physalia

Question 17

Scyphozoa

Answer 17

sea jellies

Question 18

coral and zooxanthellae relationship

Answer 18

Zoo provides: photosynthetic products (glycerol and glucose)
Coral provide: metabolic wastes (nitrogen and phosphorus)

Question 19

sea anemone and anemone fish