Does Polyplacophora have a shell?

A chiton has eight overlapping shell plates, and can, if dislodged, roll into a rough ball with its plates on the exterior. The shell has three layers, and, at least in young individuals, small tubes called aesthetes that bear photoreceptors pierce the plates.

Do Polyplacophora have a single dorsal shell?

Chitons are flattened, elongately-oval, with eight overlapping dorsal shell plates or valves, bordered by a thick girdle formed from the mantle that may be covered with spines, scales, or hairs.

How is the shell of Chitons unique?

After a chiton dies, the individual valves which make up the eight-part shell come apart because the girdle is no longer holding them together, and then the plates sometimes wash up in beach drift. The individual shell plates from a chiton are sometimes known as “butterfly shells” due to their shape.

Do Chitons molt?

Molting Isn’t Always About Skin An exoskeleton does a lot of the same things that skin does, but it also contains a chemical called chiton, which helps make it rigid like a skeleton. Birds are also somewhat unusual. They shed their skin cells gradually as most mammals do. However, they also shed their feathers.

What are 3 characteristics of Polyplacophorans?

Major Attributes:

• Possess eight calcareous plates that overlap to form a linear chain.
• Surrounding mantle developed into thick girdle, often bearing spines, scales or bristles.
• Poorly developed head.
• Lack eyes and sensory tentacles.
• Large radula with many teeth.
• Open circulatory system.
• Protostomate.

Are Chitons edible?

Its flesh is edible and has been used as a food source by Native Americans, as well as by Russian settlers in Southeast Alaska. However, it generally is not considered palatable, having a texture described as extremely tough and rubbery.

Which group has 2 shells hinged together?

Bivalves
Bivalves are mollusks that have two shells hinged together, held by strong muscles. Clams, oysters, scallops, and mussels are bivalves. This type of mollusk does not have a radula. They are mostly filter-feeders.

What is the common name for Polyplacophora?

How long does a chiton live?

Lifespan is roughly three years.

What makes Polyplacophora unique?

The main characteristics of Polyplacophora include (1) elongate or oval, dorsoventrally flattened, bilaterally symmetrical, marine; (2) with dorsal shell of eight plates embedded in a tough mantle; (3) mantle-edge stiffened (called the girdle); (4) large, muscular, ventral foot (girdle and foot can act as suction cup); …

What body part does the chiton use to eat its food?

What body part does the chiton use to eat its food? Most chitons are herbivorous and feed on algae and other sedentary organisms, including sponges, bryozoans, and coelenterates, which they scrape off the substrate or devour using a tongue-like organ, set with teeth (radula), which can be protruded and then retracted.

What is meant by chiton?

1 : any of a class (Polyplacophora) of elongated bilaterally symmetrical marine mollusks with a dorsal shell of calcareous plates. 2 [Greek chitōn] : the basic garment of ancient Greece worn usually knee-length by men and full-length by women.