Annelida(segmented worms)
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Annelida are segmented worms found worldwide in marine sediments, soils, and yards. They have bilateral symmetry, eukaryotic cells, and more than two cell layers. Their body is described as an inner digestive tract separated from an outer body wall by a coelom. There are three main types: polychaetes which are marine with many bristles on each segment; earthworms which live in soil and have a straight digestive system; and leeches which lack bristles and have dense connective tissue filling their coelom.
Annelida(segmented worms)
- 2. Introduction • In this presentation we will explain you about Annelida and the 3 major types of annelids 1) Polychaeta 2) Earthworms 3) leeches
- 3. What is Annelida? • Annelida is a group commonly referred to as segmented worms, and they are found worldwide from the deepest marine sediments to the soils in our city parks and yards.
- 4. Characteristics of Annelida • Bilaterally symmetrical and vermiform • They are eukaryotic cells • Body has more than two cell layers, tissues and organs. • Has no true respiratory organs
- 5. External features • The body of an annelid is often described as a tube within a tube. The inner tube, or digestive tract, is separated from the outer tube, or body wall, by the coelom. The head region followed by a series of segments similar to each other in appearance.
- 6. Types of Annelida-Polychaeta • The Polychaeta or polychaetes are a class of annelid worms, generally marine. Each body segment has a pair of flesh called parapodia that bear many bristles which are made of chitin. Indeed, polychaetes are sometimes referred to as bristle worms.
- 7. Types of Annelida-Earthworms • An earthworm is a tube-shaped, segmented animal that is commonly found living in soil. Its digestive system runs straight through its body, it conducts respiration through the cuticle covering its skin, and it has a simple, closed blood circulatory system
- 8. Types of Annelida-leeches • Leeches are segmented worms that belong to the phylum Annelida leeches do not have bristles and the external segmentation. Their bodies are much more solid as the spaces in their coelom are dense with connective tissues.