Biology 11 Kingdom Animalia Phylum Annelida The Segmented

Biology 11 Kingdom Animalia: Phylum Annelida: The Segmented Worms Viewer Discretion Advised: Images to come that may gross you out

• Coelomates At this point in animal evolution, a true coelom developed. So there is ______________ - and _________________ - around the skin and the gut • It also marks the point where two great lines of animal evolution diverged: the Protostomes and the Deuterostomes

The Protostomes • Contain three major phyla of animals (Annelida, Arthropoda, Mollusca) • While considered less advanced than the Deuterostomes, these phyla are the dominant animals on Earth today

Phylum Annelida Objectives By the end of the lesson you should be able to: • State the advances over Nematodes • Describe all the body systems and structures (specifically on the Earthworm) • Describe the 3 classes and their example animals (and adaptations)

Phylum Annelida The Segmented Worms – From the Latin Annellus ”little ring” Characteristics and Advances: 1. Their ______________results in muscle around the gut and more _______________. Specialization of the food tube begins 2. Nervous system has a single __________________with an anterior brain

Phylum Annelida 3. First phylum to have a _____________frees them from diffusion of materials - can grow larger. Also have “hearts” 4. Respiration through skin (land forms) by diffusion so must stay moist 5. Sexual reproduction (limited regeneration) 6. Unspecialized segmentation separated by _____________ (dividing wall)

Phylum Annelida 7. Have specialized excretory units called _______in pairs in each segment • Used as a kidney to get rid of metabolic wastes

Annelid Classes There are three major classes of Annelids: • Class ____________________: the ____________________ • Class __________: the __________

Class Oligochaeta • “few hairs” • Contains the earthworm • Move using _________ (bristles) • Fairly well adapted to land but must stay in moist environment • Head is reduced as are obvious sense organs

Class Polychaeta Tube Worms close up of mouth Cluster • Contains __________ _that are modified setae • Used as paddles (thus this class is marine) to move about - beginning of appendage development • Also used as crude gills beginning of respiratory system • Include sandworms and tubeworms

Class Polychaeta • The sandworm shows the parapodia development

Class Hirudinea _________ • These are __________ __that feed upon the blood of vertebrates including us. • Most common in fish • Can be used for medical purposes A leech in a persons eye

Annelids Video