1. Mollusks, Annelids, and Echinoderms
Alisha Horst, Cecelia King, and Amber Plank

2. Annelids intro Referred to as segmented worms
Found in deep marine sediments as well as common soils
Split into three groups: polychaeta, oligochaeta (earthworms), and hirudinea (leeches)
Polychaeta (live in almost all marine environments) is the bulk of the annelid group but the other two groups are most familiar for humans

3. Annelids characteristics
Have three body regions
Majority of the body is made of repeated sections called segments

4. Mollusks intro molluscus- Latin meaning soft
Soft bodied with an internal or external shell

5. Mollusks characteristics
Four body parts
Shell- made of calcium carbonate (CaCO3) secreted by glands in the mantle
Mantle- thin tissue covering body. Secretes the shell
Muscular foot- mouth and other feeding parts
Visceral mass- internal organs located here
Bilaterally symmetrical
Have 1 or 2 shells
Produce a trochophore (larva)

6. Mollusks life processes
Respiration
Aquatic mollusks: gills
Land mollusks: mantle cavity lined with blood vessels, “skin breathing”
Internal Transport
Sessile and slow moving mollusks: open circulatory system- blood flows into internal body cavities
Fast moving mollusks: closed circulatory system

7. Mollusks life processes cont.
Reproduction
External fertilization
Internal fertilization (mollusks with tentacles and some snails)
Cross fertilization (snails that are hermaphrodites)
Mollusk Video Clips

8. Echinoderms Groups of animals include:
Starfish, urchins, feather stars and sea cucumbers

9. Enchinoderms They are simple animals: They don’t have A brain
Complex sensing organs
Front or back end
Head

10. Echinoderms They do have: Spiny skin 5 part radial symmetry
Internal skeleton
Central mouth
Develop sharp spines for protection

11. Echinoderms They are found in a variety of shapes and colors.
They cling to coral reefs around the world
They live entirely in water

12. Echinoderms What it does:
Feeding, movement, internal transport, respiration, and excretion
Some of these animals are carnivorous, and feed and scavenge the ocean floor

13. Echinoderms
All echinoderms move around with the use of thousands of tiny tube feet, many of which have suction cups on the ends

14. Echinoderms
The most unusual feature to echinoderms is their water vascular system. It contains a network of fluid- filled canals connected to countless tube feet.