1. KINGDOM ANIMALIA: 10 PHYLA Porifera Cnidaria Rotifera Platyhelminthes
Nematoda
Annelida
Mollusca
Arthropoda
Echinodermata
10. Chordata
Invertebrates
Vertebrates

2. Ancestral
colonial protist
No true tissues
True tissues
Bilateral symmetry
Radial symmetry
Eumetazoans
Bilaterians
Protostomes
Deuterostomes
Sponges
Cnidarians
Echinoderms
Chordates
Flatworms
Molluscs
Annelids
Arthropods
Nematodes
Figure 18.4

3. Phylum Porifera Sponges Very primitive, no true tissues
Supported by spongin (protein fibers) or spicules (mineral crystals)
Sessile animals live attached to rocks.
Get food/ oxygen from water that is pumped through their hollow bodies by cells with flagella
Filter feeders
Reproduce through budding and sperm/eggs

4. Phylum Porifera

5. Flagellated choanocytes - Filter food / O2 from the water passing through the porous body
Pores
Amoebocyte
Skeletal fiber
Central cavity
Choanocyte in contact with an amoebocyte
Choanocyte
Water flow
Flagella
Figure 18.5D

6. Phylum Cnidaria Have true tissue; no organs
Have a simple skeletal system
Excretion through same opening used to pump food/ water through
Free-floating or sessile
2 stages of life cycle- medusa/polyp
Budding/sexual reproduction

7. Cnidaria: Corals, Jellyfish, Sea Anemones
Polyp stage
Medusa stage
Cnidaria: Corals, Jellyfish, Sea Anemones

8. Cnidarians have a gastrovascular cavity and cnidocytes on tentacles that sting prey
“Trigger”
Coiled thread
Capsule (nematocyst)
Discharge of thread
Cnidocyte
Prey
Figure 18.6D

9. PHYLUM ROTIFERA Very small size and mostly soft bodies
Microscopic, mostly aquatic-found in many freshwater and moist soil
Complete digestive tract with mouth and anus
Body cavities that are partially lined by mesoderm- coelomates.
Crown of cilia around the mouth of the rotifer that makes them appear to whirl like a wheel
Tiny mouths; primarily omnivorous, unicellular algae and other phytoplankton
Sexual reproduction

10. Phylum Rotifera

11. Phylum Platyhelminthes
Flatworms (tapeworms, Planaria)
3 cell layers- Acoelomates
Bilaterally symmetrical
No respiratory or circulatory systems; gastrovascular cavity and organized response mechanisms
Thin flat bodies absorb oxygen and release CO2 and wasted directly in the surrounding water.
Reproduce by splitting in 2
Some parasitic, they live in the digestive systems of other animals.

12. A planarian has a gastrovascular cavity and a simple ner vous system
Bilateral symmetry
Gastrovascular cavity
Nerve cords
Mouth
Eyespots
Nervous tissue clusters
Figure 18.7A

13. Flukes and tapeworms are parasitic flatworms
Units with reproductive structures
Scolex (anterior end)
Hooks Sucker
Colorized SEM 80
Figure 18.7B

14. Phylum Nematoda Roundworms
Less than 1 mm long; Live in soil and water.
Sexual reproduction- male sperm/female egg
Some are decomposers, others are parasites of animals or plants
Pseudocoelom; complete digestive system
Pinworms and hookworms in soil burrow into the skin of people who go barefoot outdoors; Trichina worms infest people who eat undercooked pork or wild game. (cause “Elephantitis”- swelling of appendages due to blocking of fluid movement in blood vessels by worms)

15. Phylum Nematoda

16. Phylum Annelida Earthworms, leeches- segmented worms
Each segment is separated from the next by a membrane
Closed circulatory system with blood vessels that run the length of the animal.
Has a complete excretory and digestive system where food travels through in one direction; from anterior to posterior.
Branches of the main nerves and clusters of nerve cells at the anterior end serves as a simple brain.
Live in water or damp soil; Bilateral sym
Reproduction occurs by splitting or by mutual fertilization (hermaphrodites)

17. Ear thworms and Their Relatives
Eat their way through soil
Have a closed circulatory system
Giant
Australian
earthworm
Mouth
Brain
Dorsal
vessel
Coelom
Digestive
tract
Mucus-secreting
organ
Segment
wall
Anus
Bristles
Blood vessels
Nerve cord
Pumping segmental vessels
Ventral vessel
Excretory
Segment wall
(partition
between
segments)
Epidermis
Circular
muscle
Longitudinal
Intestine
Figure 18.10A

18. Phylum Annelida (cont.)
Leeches were once used to suck out people’s “excess” blood and reduce harmful high blood pressure
Leeches are uses today to produce anti-blood-clotting medicines, to suck blood from bruises, and to stimulate blood circulation in severed limbs that have been surgically reattached..

19. Phylum Mollusca
Includes snails, clams, slugs, squid, and their relatives.
Bilateral sym.; coelomates
Radula- scrapes up food; complete digestive tract
Separate sexes; sexual reprod.
Mollusks have soft bodies with 3 parts:
A visceral mass that contains most of the organs
A muscular “foot” that is used in movement
A thick flap called a mantle, which covers the body and in most species produces a heavy shell of calcium compounds.

20. Phylum Mollusca (cont.)
Mollusks pump water through gills- both for oxygen and food for clams and oysters.
Squid and octopi use the pump for jet propulsion through the water in search of prey.

21. Phylum Mollusca

22. Diverse mollusks are variations on a common body plan
All mollusks have a muscular foot and a mantle, which may secrete a shell that encloses the visceral mass
Many mollusks feed with a rasping radula
Visceral mass
Mantle
Radula
Mouth
Nerve
cords
Foot
Digestive tract
Shell
Digestive
tract
Reproductive
organs
Heart
Coelom
Kidney
cavity
Anus
Gill
Figure 18.9A

23. Gastropods
The largest group of mollusks and include the snails and slugs
Figure 18.9B, C

24. Bivalves
Have shells divided into 2 halves and include clams, oysters, mussels, and scallops
Figure 18.9D

25. Cephalopods Adapted to be agile predators and
include squids and octopi
Figure 18.9E, F