1. Sponges - Porifera

2. Phylum Porifera - sponges --- “pore bearing”
Kingdom Animalia -Metazoans
Branch Parazoa - ‘near life’
symmetry - radial or none
no real tissues, organs or organ systems
they lack--- digestive, excretory, respiratory
circulatory, nervous (?), muscular
systems, and no appendages
respiration by diffusion ---> surface to volume ratio

3. 4 2 4 2 4 2
S.A. = (2 x 2) x 6 = 24 sq in (4 x 4) x 6 = 96 sq in
V = 2 x 2 x 2 = 8 cu in 4 x 4 x 4 = 64 cu in
S:V = 24 / 8 = / 64 = 1.5

4. Anatomy of an Asconid Sponge
Respiration
Digestion
Excretion

5. Other types of sponges have a more complex body walls,
with foldings and convolutions

6. Syconid sponges have simple folding of the body-wall
these folds form the walls of the incurrent canals
~choanocytes are only in the radial canals (the internal
folds) and do not line the spongocoel
Leuconoid sponges have the most complex body type
many chambers with choanocytes lining a
flagellated chamber

7. Structural support
Spicules
~calcareous CaCO2
~siliceous SiO2
Secreted by
sclerocytes

9. Spongin - a soft, proteinaceous, fibrous material for support

10. Reproduction -
asexual
regeneration
re-aggregation and
de-differentation
budding

11. Reproduction-
sexual
Dioecious - separate sexes
Monoecious - an individual
has both male and female
reproductive components

12. Choanocyte
epidermis
Stomatoblastula
amphiblastula