Invertebrate Phyla
Porifera
Annelida
Cnidaria
Platyhelminthes
Arthropoda
Echinodermata
Mollusca
Examples: Seasponge
Porifera means pore bearing
Asymmetry(none)
Sessile: live attached to a surface
Dont have nerve cells or tissue
FIlter feeders/ hermaphrodites
Can reassemble when fragmented
Ex: Segmented Worms, earthworms, leeches
Examples: Snails Clams Octopus Squid
Body is divided into many sections
complete digestive tract
- Pharynx
2.Esophagus - Crop
- Gizzard
- Intestine
Closed circulatory system
Blood stays within vessels - Main Vessel is dorsal
- 5 aortic arches
Earth worm is a hermaphrodite
Ex: Coral Jellyfish Sea Annenomea
Cnidocytes: cells that contain stinging poisonous barbs which the use to paralyze prey
Radial symmetry (division of 5 equal parts)
2 body forms:
Polyp: sessile, tentacles up- coral hydra
Largest Phylum
Characteristics:
Exoskeleton
Doesn't grow so it must shed
Paired jointed appendages
segmentation
open circulatory system
Ventral nerve cords
Examples: Falt worms, tapeworms, fluke
Many parasitic forms which causes different diseases in humans and livestock
Bilateral symmetry and Cephalization which is the concentration of sensory organs and nervous tissue in the head
One digestive opening to take in food and release waste
Most are hermaphrodites
Name means skinny spine
Marine environment
Radial symmetry
Body parts are usually in pairs of 5's
Water vascular system
Tube feet
Have true coelom (Body Cavity)
Muscular foot- used for motion or attachment
Mantle soft outer layer
Visceral Mass- contains most of the organs
Gills/ lungs
Most have different sexes but some are hermaphrodites
Main groups:
1.Gastropods
univalves- one shell, breathe with lungs
bivalves- 2 shells, breathe with gills
- cephlopods
Examples: Starfish, Sea Urchins, and sea cucumbers
Examples: Centipedes, millipedes, scorpions
Centipede/ millipedes
- most primitive arthropods
- obvious segmentation
- centipedes (Class Chilipoda
Millipedes (Class Diplopoda)
a. Two pairs of legs per segment
b. one pair of short antennae
Crustaceans
Most are marine
2 body regions - Cephalothorax
- Abdomen
2 pairs of antennae
Swimmerets- appendages on abdomen used for swimming
Breathes by gills attached to swimmerets
One pair of large claw and 4 pairs of walking legs