What annelids do polychaetes include?

Polychaetes, which include rag worms, lugworms, bloodworms, sea mice, and others, are marine worms notable for well-defined segmentation of the body. Unique among annelids, most polychaete body segments bear a pair of parapodia (flat, lobelike outgrowths) with setae, or tiny bristles.

1. Are all marine annelids polychaetes?
2. Why do polychaetes differ from other annelids?
3. What is the difference between Metameres and Septa?
4. What characteristics do polychaetes have?
5. What do polychaetes have?
6. What kind of animal is a polychaete?
7. Where are most polychaetes found?
8. How do polychaetes differ from polychaetes?
9. What is the difference between leeches and polychaetes?
10. Which of the following would be a characteristic that make polychaetes unique to other annelids?
11. What are the 3 classes of annelids?

Are all marine annelids polychaetes?

The Polychaeta /ˌpɒlɪˈkiːtə/, also known as the bristle worms or polychaetes, are a paraphyletic class of annelid worms, generally marine. ... Only 168 species (less than 2% of all polychaetes) are known from fresh waters.

Why 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.

What is the difference between Metameres and Septa?

What is the difference between metameres and septa? External segments are called metameres and internally, septa, or dividing walls, are located between the segments.

What characteristics do polychaetes have?

The known species of polychaetes share only a few characteristics. Each has a head, a tail and a segmented body, and typically each body segment has a pair of leg-like parapodia with spiny bristles sticking out. It's these bristles that give the worms their name: "polychaete" is Greek for "with much hair."

What do polychaetes have?

Polychaetes include such forms as sand worms, tube worms, and clam worms. Most have well developed, paired, paddle-like appendages (parapodia), well developed sense organs, and numerous setae (usually on the parapodia; "polychaete" means "many hairs").

What kind of animal is a polychaete?

polychaete, any worm of the class Polychaeta (phylum Annelida). About 8,000 living species are known. Polychaetes, which include rag worms, lugworms, bloodworms, sea mice, and others, are marine worms notable for well-defined segmentation of the body.

Where are most polychaetes found?

Polychaetes are multi-segmented worms living in all environments in the world's oceans, present from abyssal depths to shallow estuaries and rocky shores, and even free swimming in open water. They are strictly aquatic annelids, but are the most abundant and diverse group of Phylum Annelida.

How do polychaetes differ from polychaetes?

Polychaetes refer to the marine annelids, with unsegmented swimming appendages with many chaetes. Meanwhile, oligochaetes refer to the hermaphroditic terrestrial or aquatic annelids that lack a specialized head.

What is the difference between leeches and polychaetes?

Polychaetes are the most diverse group of annelids and most live in the marine environment. They differ from earthworms and leeches in that they have appendages called parapodia and do not possess a clitellum. In size they range from 1 mm (0.04”) to 3 m (10') but most are around 10 cm (4”).

Which of the following would be a characteristic that make polychaetes unique to other annelids?

Polychaetes are distinguished from other annelids by having pairs of appendages called parapodia attached to the outside of each segment. ... The parapodia are filled with tiny blood vessels that can absorb oxygen through the surface of these appendages.

What are the 3 classes of annelids?

Critical appraisal. Most authors accept the annelids as having three major classes: Polychaeta, Oligochaeta, and Hirudinea. Older systems would place the polychaetes and oligochaetes under the class Chaetopoda because both groups possess setae.