Download Porifera - Taran D. Thompson

Porifera
https://www.youtube.com/watch?v=8gNJClc0ng4
What is a Sponge???
Metazoans
Multicellular animals (3 grades)
• Mesozoa - tiny worm-like parasites, few species
• Parazoa - no true germ layers
– Placozoa (single species!)
– Porifera (the Sponges!)
• Eumetazoa – true germ layers, all other phyla!
Porifera = Sponges
Characteristics
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Multicellular, loose aggregation of cells
Body of pores, canals, chambers
All aquatic, most marine
No organs or true tissues
Sessile – does not move
Unique Cells
 Choanocytes
 Flagellated cells that
create current through
the sponge
 Also used in feeding
https://www.youtube.com/watch?v=8ueKlS
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Structure (skeleton)
• Spongin
– Fibrous protein made
of collagen
• Spicules
– Skeleton of needle-like
spikes
Can be made of calcium, silica
or a protein called spongin.
Respiration, Circulation, Excretion
• Choanocytes
– Creates current of water to get oxygen
– Get rid of waste from all cells
• Ostium
– Small intake pores, water goes IN
• Osculum
– Large opening, water goes OUT
Nutrition/Digestion
• Choanocytes
- use collar to filter out small particles of food
• Archeaocytes
- move food around within the sponge
• Pinacocytes
– Absorbs nutrients
Reproduction
• Both Asexual and Sexual
Reproduction
• Choanocytes produce
eggs and sperm,
although not produced at
same time.
(monoecious)
WHY????
Broken off sponge can
produce more sponge
Certain Choanocytes will lose
their flagella and undergo
meiosis
Asexual
Reproduction
Nervous System
• No real nervous system.
• All instructions are at the cellular level….
nucleus
Each cell only controls
itself… No Brain to
control all cells
Water Flow in a Sponge
Name the cells!
Types/Body Shapes of Sponges
• Asconoid
• Syconoid
• Lueconoid
Asconoid
• one simple canal
from pore to
central cavity or
atrium called the
SPONGOCOEL
• Small, tube
shaped sponges
Syconoid
• Folded wall with
canals from pore to
smaller canal that
then goes to the
larger central cavity
(atrium)
• Tube-shaped
sponges
Leuconoid
• Many canals from pore
to smaller incurrent
canals that branch
repeatedly before
arriving at the larger
central cavity
SPONGOCOEL
• Most complex of plans,
biggest sponges
• greatly increases food
collection surfaces
Food Chain
• Angel fish and hawkbilled sea turtles
Rock Beauty Angel
Why don’t more animals eat
sponges???
Symbiotic relationships
Fairy Crab hiding in the crevice
of a barrel sponge
Brittle sea star on an Azure
vase sponge
Human Use of Sponges
Sponge Industry Nearly brought
Many sponges close to extinction
Demosponges – soft, flexible,
strong