basal animals; sponges, corals and jellyfish

Question 1

porifera

Answer 1

sponges

Question 2

porifera characteristics

Answer 2

• vase shaped
• no clear nerve cells or muscles
• move slowly
• respond to touch/sense chemical change sin environment
• do not have true mouth or gut (filter feed)
• have one or morelarge pores/holes on surface
• have choanocytes
• ‘tissue level organization’
• some have regenerating powers
• connective tissue with protein fibres

Question 3

choanocytes

Answer 3

‘feeding cells’ in sponges; have beating flagellum
-have large cross-sectional areas to slow down water flow and allow for sponge cells to engulf bacteria and food particles

Question 4

examples of sponges

Answer 4

spongia

hippospongia

Question 5

uses of sponges

Answer 5

clean wounds
reduce swelling
treat swings
used by dolphins to protect themselves in food foriging
synthethic foams for washing

Question 6

porifera classes

Answer 6

Demospongia (bath sponges)

Calcarea (calcium carbonate spicules)

Hexactinellida (deep sea; glass sponges)

Question 7

hexactinellida feature

Answer 7

• deep sea
• glass ponges
• much of their body made of syncytia (cytoplasm sheets)
• have silica spicules

e.g. venus flower basket

Question 8

non bilaterians

Answer 8

sponges
cnidarians
ctenophora
placozoa

Question 9

trichoplax

Answer 9

trichoplax adharens; stick hairy plate

• in placozoa phylum
• can be easly confused with amobea
• irregular flattened shape
• feeds using enzymes for external digestion

Question 10

placozoans

Answer 10

e. g. trichoplax adharerns
- discovered by Schulze
- found in aquariums

Question 11

ctenophora

Answer 11

comb jellies; slow moving predators

• biradial symmetry
• bump into small planktonic animals and ensare them with glue (from specialized cells)
• have nerce cells and balance sense organs
• have 8 combs that run as strips along body
• cilia beat in coodrnation with metachronal waves

Question 12

ctenophora examples

Answer 12

pleurobrachia
cestum veneris (venus girdle)

Question 13

cnidaria

Answer 13

jellyfish, sea anomones, corals

• have radial/rotational/no symmetry
• cup shaped/flask shaped
• single large opening that acts as both mouth and anus
• tentecles with stinging cells called cnidocytes
• nerve cells in lattice like netework
• mesoglea separates etcoderm and endoderm

Question 14

cnidarian groups

Answer 14

anthozoans (sea anomones and corals)
hydrozoans (hydra; e.g. portugese man of war)
cubozoans (box jellies)

Question 15

special about corals?

Answer 15

coloniality
form a giant super organism
secret calcium carbonate
use zooxanthelle filter feeders

Question 16

polyp

Answer 16

mouth up orientation of cnidarian

e.g. sea anomes, corals, hydra

Question 17

medusa

Answer 17

mouth down orientation

e.g. jellyfish or scyphozoans

Question 18

rhizostomate

Answer 18

order o fjellyfish ;
multitide of tiny mouth like openings
eight branching arms
- supplement food using symbiotic algae (e.g Mastigias papua)

Question 19

cubozoans

Answer 19

box jellies
24 eyes
e.g. australia sea wasp
- toxic stings