Bell ringer 3/3 What makes roundworms different than flatworms? What advantages do they have over the other? Would you trade your flatworm child for a roundworm? Announcements: Correct your test this weekend if you want to retake next week.

Label the round worm on your Webquest note sheet

ANNELIDS Kingdom- Animalia Phylum- Annelida

Characteristics of Segmented Worms Phylum Annelida Meaning – anellus = tiny ring Bilaterial symmetry; coelom; 2 body opening; bodies are cylindrical and segmented Habitat Most environments except: frozen soil and dry sand / soil Locomotion All use setae (tiny bristles on each segment)

Characteristics of Segmented Worms Reproduction Hermaphrodites (earthworms and leeches) Sexual reproduction via mating (bristle worms) Feeding Complete digestive track Eat soil or blood Significance Earthworms aerate and fertilize the soil Leeches are used medically for limb reattachment

Characteristics of Segmented Worms Examples: Earthworms Leeches Bristleworms Lug worms Plumed worms Sea mice Fan worms

Setae On the outside of each segment, annelids have little bristle-like structures called setae that help them move. Segmented worms also use the setae to help them stay in the soil if a bird gets a hold of them!

Segmented Worms all segmented worms have a body cavity that holds their organs.

Earthworms Earthworms eat soil. They use their crop for storage and their gizzard to grind the soil. Digested food moves to the intestine where it is broken down and absorbed by the blood. Undigested soil and waste leave the worm through the anus.

Pictures of Segmented Worms

Classes There are three classes of annelids: Class Polychaeta: marine annelids; Class Oligochaeta: marine, freshwater and terrestrial annelids including earthworms; Class Hirudinea: marine, fresh water and terrestrial leeches.

The "medicinal leech" feeding on blood from a human arm. Leeches Leeches feed on the blood of animals- including humans. They have two suckers that they use to attach to the animal. It will then cut into the flesh and suck out blood. Leeches produce an anesthetic so that the animal doesn’t feel the bite. For centuries leeches were used for blood letting because of the mistaken belief that bodily disorders and fevers were caused by an excess of blood. Today leeches are used to keep blood flowing to reattach body parts. The "medicinal leech" feeding on blood from a human arm.

Bell ringer 10/7 Sit with your lab partner. Read over the list of 20 interesting facts about earthworms. Identify the 2 that you find the most interesting.

Marine Worms Marine worms also have segments with setae. Some marine worms trap food in tentacles. Others build tubes to hide in.

Bell ringer 10/26 We compared 2 worms in lab: planaria & earthworms. Describe the similarities between the 2 worms. Describe the differences between the 2 worms. Pull out all of the following: unsegmented & segmented worm note sheet. Worm webquest Announcements: Worm quiz tomorrow!! Clam dissection on Monday?

Leech Therapy

Bell ringer 10/27 Complete the flatworm, round worm, and segmented worm rows on your phylum comparison chart. Announcements: Worm quiz today!! Clam dissection on Monday? Retakes on Sponges & Cnidarian test next week. Science Club Today! 

After the Quiz Put your quiz by the fish. Start working on the Mollusk reading and coloring guide

Worm Review

Review Questions Recall 1. What is cephalization? 2. Name a parasitic flatworm. 3. Name a parasitic segmented worm. 4. Earthworms are in what phylum? Apply Concepts 5. Are all worms classified into a single phylum? 6. Describe the respiratory system of the flatworms. 7. How does the body plan of the roundworms differ from that of the flatworms? 8. Describe the digestive system of roundworms. 9. What features distinguish Phylum Annelida from the other worms? 10. Describe the skeletal system of a segmented worm. Critical Thinking 11. Which phylum includes worms with organs that are most similar to the organs found in humans? Support your answer with three pieces of evidence.  

Closing – Crumble and Toss Get a piece of paper How does the structure of the segmented worm affect its function? Planarian?