PORIFERA

Question 1

what describes Porifera?

Answer 1

• no fixed body shape
• no plane of symmetry
• covered in holes
• cells are un coordinated
• cell differenciation is entirely reversivle
• cells may wander about
• regeneration from a few separated cells
• colonies of separate cells
• simplest multicellular animals

Question 2

when did porifera emerge?

Answer 2

530 million years ago

Question 3

how many living species?

Answer 3

15 000

Question 4

what 3 things are distinguishing characters of sponges?

Answer 4

• sessile
• immobile
• lacking nerves and muscles

Question 5

3 cell types of sponges

Answer 5

• choanocytes
• pinacocytes
• amoebocytes (mesohyl)

Question 6

spicule

Answer 6

used as a skeleton

Question 7

archaeocyte

Answer 7

can be anything at any time. wander thru mesohyl. sometimes sperm, sometimes egg, sometimes collar cell

Question 8

sclerocyte

Answer 8

makes the spicules. ‘sclero’ means hard

Question 9

Mesohyl

Answer 9

means a matrix of some sort of tissue

Question 10

pinacocyte

Answer 10

forms the outside of the cell, gives it some sort of rigidity

Question 11

choanocyte

Answer 11

collar-cell. these cells move water. b/c food, feces and reproduction

Question 12

Ostium/ostia

Answer 12

one ostia, pleural ostium. Pore.

Question 13

what are the four cell layers of a sponge?

Answer 13

spongocoel
chaonoderm
mesohyl
pinacoderm

Question 14

describe a sponge’s skeleton

Answer 14

• calcite
• silica
• w/wo collagen type protein
• diverse
• function: prevent movement, keep shape

Question 15

what are the three types of sponges?

Answer 15

• calcarea
• demospongiae
• hexactinellida

Question 16

Calcarea

Answer 16

• calcareous spicules

- shallow water (less than 100m)

Question 17

Demospongiae

Answer 17

siliceous spicules

• breadcrumb sponge
• bath sponge

Question 18

what is the black covering on bath sponges called?

Answer 18

pellicle

Question 19

where is it common to fish for bath sponge?

Answer 19

gulf of mexico, caribbean, mediterranean

Question 20

how are sponges fished for?

Answer 20

trawling, diving, intertidal collection

Question 21

how is the processing done for commercial sponges?

Answer 21

open air to die
back in marine to remove pellicle
beaten to remove non-associated organic parts
bleached to give yellowish color

Question 22

Hexactinellida

Answer 22

• glass sponges
• 400-500 spp
• below 200m
• no pinacocytes
• no cells with contractility
• skeleton of 6 rayed spicules of silica

Question 23

when did sponge reefs emerge?

Answer 23

145mya (jurassic)

Question 24

where in BC do we find sponge reefs?

Answer 24

• hecate straight
• sunshine coast
• straight of georgia
• galiano

Question 25

Choanocytes- feeding

Answer 25

• create water currents
• trap food
• collar= ring of 30 small folds. microvilli
• base collar= food absorbed
• canals and flagellated chambers
• amoebocytes help circulate the food
• digestion is intracellular

Question 26

Poriferan Feeding

Answer 26

• filter feeders
• can phagocytize
• can harbor symbiotic photosynthetic organisms in mesohyl
• ie dinoflagellates (zooxanthellae)
• ie cyanobacteria (blue green algae)

Question 27

an example of cellular communication

Answer 27

osculum will close when touched

Question 28

can a sponge regenerate? how?

Answer 28

yes. self-recognition when cells are smashed or separated from each other

Question 29

how do sponges reproduce?

Answer 29

asexually:
-genetically identical to previous generation . gemmules, budding
sexually:
-genetically different from previous generation, sharing of gametes. hermaphroditic, dioecious

Question 30

colonial theory:

Answer 30

choanoflagellate colony with mono ciliated collar gave rise to sponges

Question 31

______ to which cells are attached is universal in the metazoa

Answer 31

ECM (extra cellular matrix)

Question 32

choanoflagellates are virtually identical to what cells in metazoan sponges?

Answer 32

choanocytes. collar cells

Question 33

how have sponges become so successful?

Answer 33

• morphological simple but successful

- complexity of form is not the only route to success

Question 34

IMTA

Answer 34

integrated multi trophic aquaculture?