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How do segmented worms reproduce asexually


Annelidphylum name Annelida, also called segmented wormany member of a phylum of invertebrate animals that are characterized by the possession of a body cavity or coelommovable bristles or setaeand a body divided into segments by transverse rings, or annulations, from which they take their name. The coelom is reduced in leeches, and setae are lacking a few specialized forms, including leeches. A major invertebrate phylum of the animal kingdom, the annelids number more than 9, species distributed among three classes: The brain of most annelids phylum Annelid a; segmented worms, including the leeches and terrestrial How do segmented worms reproduce asexually is relatively simple in structure.

The earthworm brain is a bilobed mass lying above the pharynx in the third body segment. Sensory nerves leave the brain and run forward…. Annelids are found worldwide in all types of habitats, especially oceanic waters, fresh waters, and damp soils. Most polychaetes live in the ocean, where they either float, burrow, wander on the bottom, or live in tubes they construct; their colours range from brilliant to dull, and some species can produce light.

The feather duster Manayunkia speciosa inhabits the Great Lakes and some rivers of the United States. The polychaetes include more than 6, known species, which are about evenly divided between free-moving and tube-dwelling forms. The oligochaetes number about 3, known species. Oligochaetes, including earthworms, burrow into soil; certain small oligochaetes are found in fresh water, and a few are marine, usually inhabiting estuarial or other shallow waters.

Annelids, or segmented worms, reproduce...

Leeches, which number about species, inhabit freshwater or humid environments and are carnivorous or parasitic on other organisms— e. The length of annelids varies from a fraction "How do segmented worms reproduce asexually" an inch to more than six metres about 20 feet.

The width may exceed 2. Free-moving polychaetes and earthworms include the largest species. Leeches attain lengths of about 0. The body of free-moving polychaetes see figure consists of a head, or prostomium, which may bear two or more eyes; a preoral segment, with such appendages as antennae, tentacles, and palpi fleshy sensory projections ; a trunk divisible into distinct segments; and a tail, or pygidium, which may bear anal cirri fleshy projections or plaques and a terminal anus.

Each body segment following the second segment peristome usually has paired parapodia; i.

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