What are the characteristics of a trochophore?

What are the characteristics of a trochophore?

trochophore, also called trochosphere, small, translucent, free-swimming larva characteristic of marine annelids and most groups of mollusks. Trochophores are spherical or pear-shaped and are girdled by a ring of cilia (minute hairlike structures), the prototroch, that enables them to swim.

Is polychaete a larva?

The Larva of planktonic Annelids are known as trocophore, which are translucent, motile zooplankton characteristic of the class Polychaeta, as well as most Mollusk species. Being marine worms, Polychaete trocophore are found in oceans around the planet, and are especially abundant among coastal plankton populations.

Are polychaete worms plankton?

Most polychaetes are meroplankton, meaning that they are plankton only for their egg and larval stages. When they reach a certain size, they settle out of the water column and spend their adult lives associated with some kind of substrate (e.g., reefs, sand, mud, rock, etc.).

What is the name of the larval stage of polychaetes?

trochophore larva
The trochophore larva of polychaetes is typically diamond-shaped with a circle of short, hairlike projections (cilia), called the prototroch, around the thickest part of the body. Cells bearing the prototroch develop from specific micromeres at the 16-cell stage.

What is the trochophore function?

A trochophore (/ˈtroʊkəˌfɔːr, ˈtrɒ-, -koʊ-/; also spelled trocophore) is a type of free-swimming planktonic marine larva with several bands of cilia. By moving their cilia rapidly, they make a water eddy, to control their movement, and to bring their food closer, to capture it more easily.

What is the evolutionary significance of trochophore larva?

Trochophore larva has a prominent status in the evolutionary context. Studies are suggestive of the Trochophore larva as a bridge between radial and bilateral symmetry. The larval form shows similarities with many invertebrate groups.

How do polychaetes differ from other annelids?

Polychaetes differ from other annelids in having a well differentiated head with specialized sense organs and no clitellum. They have many setae, usually arranged in bundles on the parapodia. The sense organs in polychaetes are more highly developed than in oligochaetes.

Why nereis is called polychaete?

Nereis possess setae and parapodia for locomotion. They may have two types of setae, which are found on the parapodia. Locomotor chaetae arefor crawling, and are the bristles thatare visible on the exterior of thePolychaeta. they are cylindrical in shape.

What are the characteristics of a polychaete?

Most have well developed, paired, paddle-like appendages (parapodia), well developed sense organs, and numerous setae (usually on the parapodia; “polychaete” means “many hairs”). Polychaetes usually have a well-developed head, often complete with well-developed eyes, antennae, and sensory palps.

How do Polychaetes differ from other annelids?

Do all mollusks have trochophore larvae?

Molluscs include such familiar creatures as clams, oysters, snails, and octopi. They share a distant common ancestor with the annelid worms, an evolutionary heritage suggested by their larval form, called a trochophore larva, found in all molluscs and in certain marine annelids called polychaete worms.