1. Warm Up:
Describe some ways that we group invertebrates based on their “body plan”
Symmetry, tissue, body cavity, development (protostome vs deuterstome)

2. Diversity of Invertebrates
(Sections )

3. Objective Checklist
Describe the major characteristics of invertebrates:
Members
Structure
Feeding
Movement
Reproduction
Evolutionary milestone

4. Introduction Invertebrates are animals that lack a backbone
They account for 95% of known animal species

5. Porifera Ex: Sponges Asymmetrical, collection of animal-like protists
Filter feed
Sessile
Asexual budding & regeneration OR sexual
Multicellular

6. Azure vase sponge (Callyspongia plicifera)
Fig. 33-4
Food particles
in mucus
Flagellum
Choanocyte
Choanocyte
Osculum
Azure vase sponge (Callyspongia
plicifera)
Spongocoel
Phagocytosis of
food particles
Pore
Figure 33.4 Anatomy of a sponge
Water
flow

7. Cnidaria Ex: jelly fish, hydra, anemones, coral
Soft bodies with stinging cells, radial symmetry

8. Cnidaria
Food is brought into gastrovascular cavity by tentacles; incomplete digestive tract
Motile medusa; sessile polyp
Asexual through budding or sexual
True tissues; nerve net and contractile fibers
Polyp
Medusa

9. Platyhelminthes Ex: flatworms (planarians, flukes, tapeworms)
Unsegmented worms with flattened bodies; acoelomate
Mouth parts vary; incomplete or absent digestive tract
Crawl using muscles
Asexual regeneration or sexual
Bilateral symmetry
Flukes - Schistosomiasis /ˌʃistəsɵˈmaɪəsəs/ (also known as bilharzia)[1] is a disease caused by parasitic worms of the Schistosoma type. It may infect the urinary tract or intestines. Symptoms may include: abdominal pains, diarrhea, bloody stool, or blood in the urine. In those who have been infected a long time, liver damage, kidney failure, infertility, or bladder cancer may occur. In children it may cause poor growth and difficulty learning.[2]
The disease is spread by contact with water that contains the parasites. These parasites are released from freshwater snails that have been infected. The disease is especially common among children in developing countries as they are more likely to play in infected water. Other high risk groups include farmers, fishermen, and people using infected water for their daily chores. Diagnosis is by finding the eggs of the parasite in a person's urine or stool. It can also be confirmed by finding antibodies against the disease in the blood.[2]
Methods to prevent the disease include improving access to clean water and reducing the number of snails. In areas where the disease is common entire groups may be treated all at once and yearly with the medication praziquantel. This is done to decrease the number of people infected and therefore decrease the spread of the disease. Praziquantel is also the treatment recommended by the World Health Organization for those who are known to be infected.[2]
Schistosomiasis affects almost 210 million people worldwide,[3] and an estimated 12,000[4] to 200,000 people die from it a year.[5] The disease is most commonly found in Africa, Asia and South America.[2] Around 700 million people, in more than 70 countries, live in areas where the disease is common.[6][5] Schistosomiasis is the parasitic disease that has the second greatest economic impact, the first being malaria.[7]

10. Nematoda Ex: Roundworms (hookworms, whipworms, pinworms, etc)
Worm with tough exoskeleton; central nervous system
Sharp mouth parts; complete digestive tract
Whip-like using muscles
Sexual reproduction
Psuedocoelom

11. Mollusca
Ex: Gastropods (snails), Bivalves (clams) and Cephalopods (squid)
Soft-bodied; some have shells
Rasping mouth parts, or filter feed

12. Mollusca Muscular foot or squeezing propulsion Sexual reproduction
Coelom (bathes organs in blood) in some
Aside: Cephalopods have closed circulatory and well developed brain

13. Annelida Ex: Earthworms, leeches, and marine worms
Segmented, coelomate, closed circulatory system, brain
Most eat organic waste; complete digestive tract

14. Video: Earthworm Locomotion
Annelida
Crawl using muscles
Asexual fragmentation followed by regeneration or sexual reproduction
Body segmentation
Video: Earthworm Locomotion

15. Arthropoda Ex: arachnids, crustaceans, centipedes, insects
2/3 known species of animals are arthropods!!!
Ex: arachnids, crustaceans, centipedes, insects
Exoskeleton made of chitin; segmented body, brain and sense organs

16. Arthropoda Eat organic matter; mouth parts vary
Jointed appendages; fly, swim, crawl, jump
Sexual; eggs or live young
Jointed appendages

17. Arthropods Aside on respiration
Spiracles, trachea, gills, and/or book lungs.
Open circulatory system

18. Arthropoda Aside on Metamorphosis
Incomplete metamorphosis - The young resemble adults but are smaller
Complete metamorphosis - Larval stage looks entirely different form the adult stage

19. Echinodermata Ex: Seas stars, sea urchins, sea cucumbers
Radial symmetry(bilateral as larvae though)
Complete digestive tract; filter feed, graze on algae, or prey on other animals
Sessile or slow moving
Asexual regeneration and sexual
Deuterostome

20. Echinodermata Aside on Sea Star Structure
Endoskeleton made of calcium - based plates
Water-vascular system to store water and to fill the tube feet for movement
Each arm has nerves, digestive and reproductive organs

21. The End!