What lengths can polychaetes reach?

1. What is unusual about the jaws of some polychaetes?
2. Where are polychaetes found?
3. What physical characteristics do all polychaetes have in common?
4. How many polychaetes are there?
5. How long does a bristle worm live?
6. How do polychaetes move?
7. How do polychaetes survive in the wild?
8. Do polychaetes live in freshwater?
9. How do growing polychaetes add segments?
10. Are all polychaetes Marine?
11. What type of body organization is found in polychaetes?
12. Where do bristle worms live?
13. How do you feed sessile polychaetes?
14. Are polychaete worms decomposers?

What is unusual about the jaws of some polychaetes?

In general, however, they possess a pair of jaws and a pharynx that can be rapidly everted, allowing the worms to grab food and pull it into their mouths. In some species, the pharynx is modified into a lengthy proboscis.

Where are 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.

What physical characteristics do all polychaetes have in common?

physical characteristics

Body elongated and flattened with conspicuous parapodia with bristles. The head has four eyes, two antennae, and two palps. Has eversible pharynx; armed with chitinous teeth. Color is greenish during spawning season and varies from red to light brown at other times.

How many polychaetes are there?

polychaete, any worm of the class Polychaeta (phylum Annelida). About 8,000 living species are known.

How long does a bristle worm live?

They can live for years, I have had several in my tanks over 3 feet long. Bristle worm populations are limited by food source, if you feed too much the population grows.

How do polychaetes move?

Locomotion in free-moving polychaetes is accomplished by circular, longitudinal, and parapodial muscles and by coelomic fluid. ... Body undulations, which help the worm to move rapidly, are produced by the contraction of longitudinal muscles stimulated by the backward stroke of parapodium of a particular segment.

How do polychaetes survive in the wild?

The researchers suspect that these polychaetes survive by feeding on free-living bacteria on the gas hydrate's surface. They may also encourage the growth of their own bacterial food; their waving parapodia create water currents along the surface of the hydrate, delivering fresh oxygen for themselves and the bacteria.

Do polychaetes live in freshwater?

Polychaeta is a commonly encountered group of annelids (segmented worms) best represented in the marine environment, although several species are present in freshwater and a few are known from moist soil on land.

How do growing polychaetes add segments?

In both polychaetes, larval segments arise from a field of dividing cells located in lateral regions of the body, rather than from a localized posterior growth zone. Circumferential expansion of the forming segmental tissue is particularly pronounced in Capitella sp.

Are all polychaetes Marine?

Polychaetes are a large and extremely diverse group. Around 10,000 species have been described. Most are marine. Some, such as featherduster worms, are sedentary, living in tubes buried in sand or mud, and feed by trapping food particles in mucus or by ciliary action.

What type of body organization is found in polychaetes?

The body in many species, especially in the sedentary polychaetes, is separated into two or three regions. The cells constituting the epidermis (outermost cell layer) are usually simple columnar epithelial cells covered by a cuticle; parts of the body may be ciliated, especially in smaller forms.

Where do bristle worms live?

A bristle worm is a small, cryptic (lives in dark parts of your reef) segmented worm that often lives in a reef aquarium's live rock and sand. The “bristle” part of their name comes from the tufts of hair that poke out between each segment. These “hairs” provide protection from predators.

How do you feed sessile polychaetes?

Some filter and deposit feeding polychaetes have large spirals of feather-like tentacles that they expand out of their tube and into the water to "catch" food. Other filter and deposit feeding polychaetes move water, and prey, through their burrows by moving their parapodia.

Are polychaete worms decomposers?

They also play an important role as decomposers in the ecosystem.