Many species have a feeding structure, the radula, found only in mollusks. The radula can be thought of as a "tongue-like" structure. The radula is made mostly of chitin. Types of radulae range from structures used to scrape algae off of rocks to the beaks of squid and octopuses.

What is the radula in molluscs made of?

The radula apparatus consists of two parts : the cartilaginous base (the odontophore), with the odontophore protractor muscle, the radula protractor muscle and the radula retractor muscle. the radula itself, with its longitudinal rows of chitinous and recurved teeth, the cuticula.

What is a radula in molluscs?

The radula is the anatomical structure used for feeding in most species of Mollusca. Previous studies have revealed that radulae can be adapted to the food or the substrate the food lies on, but the real, in vivo forces exerted by this organ on substrates and the stresses that are transmitted by the teeth are unknown.

What structure supports the radula of molluscs?

It is supported by a cartilage-like mass (the odontophore) and is covered with rows of many small teeth (denticles). New sections are constantly produced to replace teeth worn away at the front.

What is the radula function in mollusks quizlet?

The radula (plural radulae or radulas) is an anatomical structure that is used by molluscs for feeding, sometimes compared rather inaccurately to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food enters the esophagus.

Mollusca | Gastropods-Bivalves-Cephlapods |

How do mollusks use Radula?

The radula is a feeding organ with teeth made of chitin. ... Herbivorous mollusks use the radula to scrape food such as algae off rocks. Predatory mollusks use the radula to drill holes in the shells of their prey. Mollusks have a coelom and a complete digestive system.

What is the characteristic that unites all mollusks?

They have ink glands that they use to defend themselves or escape from predators. They show all the characteristic features of Phylum Mollusca and are triploblastic, bilaterally symmetrical, and found in various regions of the ocean.

What is the function of radula give the name of the group of molluscs which do not possess a radula?

The radula is unique to the molluscs, and is found in every class of mollusc except the bivalves, who use instead cilia, waving filaments that bring minute organisms to the mouth. Within the gastropods, the radula is used in feeding by both herbivorous and carnivorous snails and slugs.

What organ systems do molluscs have?

• Most mollusk have two organs that are unique to this phylum: a specialized feeding organ called a radula and a dorsal layer of tissue called a mantle.
• Mollusks are the first animals to have evolved organ systems for respiration and circulation.

Does Mollusca have open circulatory system?

Most mollusks have an open circulatory system but cephalopods (squids, octopus) have a closed circulatory system. The blood pigment of mollusks is hemocyanin, not hemoglobin. ... Most mollusks have separate sexes but most snails (gastropods) are hermaphrodites.

What is the radula in a gastropod?

Radula in Gastropods. Most Mollusks (with the exception of bivalves) have a specialized feeding organ within the mouth called the radula. The mouth opens into a pocket-like buccal cavity. Inside this cavity is the radula sac which protects the mouth when the radula is not in use.

What phylum do you find radula?

Answer: The radula is unique to the molluscs, and is found in every class of mollusc except the bivalves, who use instead cilia, waving filaments that bring minute organisms to the mouth. Within the gastropods, the radula is used in feeding by both herbivorous and carnivorous snails and slugs.

What secretes the shell in molluscs?

In shelled molluscs, the mantle is the organ that forms the shell, and adds to the shell to increase its size and strength as the animal grows. Shell material is secreted by the ectodermic (epithelial) cells of the mantle tissue.

Which set of body parts does every mollusk have?

Despite their diversity, mollusks share in common a three-part body plan that includes a head, a foot and a visceral mass.

What is the larval stage of mollusks called?

Both mollusks and annelids develop through a larval stage called a trochophore larva.

What type of digestive system is present in molluscs?

6. Clams (and all mollusks) have a complete digestive system. It consists of a mouth where food is ingested, a short connecting tube called the esophogus, a stomach which temporarily holds food, and an intestine where food digestion and absorption takes place.

What type of circulatory system does a mollusk have?

Mollusks possess an open circulatory system in which body fluid (hemolymph) is transported largely within sinuses devoid of distinct epithelial walls. The posteriodorsal heart enclosed in a pericardium typically consists of a ventricle and two posterior auricles.

What is the respiratory organ of Mollusca?

A ctenidium is a respiratory organ or gill which is found in many mollusks.

What is the function of radula which animal contain this structure?

Radula is a file like rasping organ which is used for feeding by molluscs. It bears teeth like structure which help in scraping the food from rocks and other substances.

What is the function of radula Class 11?

The radula is an anatomical structure used by molluscs for feeding, which is also sometimes compared to a tongue. The radula is present in the buccal cavity of a mollusc. It is a minutely toothed, chitinous ribbon, that is usually used for scraping or cutting food.

What is the other name for the Gill of a mollusc What is the function of Osphradium?

Answer: The other name for the gill of mollusk is CTENIDIUM. Osphradium functions as a sensory organ in some mollusks which has chemoreceptors which test the water which in ingested by the animal.

What is the common characteristic of mollusks and crustaceans *?

Crustaceans are aquatic animals that have jointed legs, a hard shell and no backbone, such as crab, crayfish, lobster, prawns and shrimp. Most molluscs have a hinged two-part shell and include clams, mussels, oysters and scallops, as well as various types of octopus, snail and squid.

What three characteristics do all molluscs share that make them molluscs?

• Unsegmented soft body with bilateral symmetry.
• Presence of an internal or external shell.
• A toothed tongue (made mostly of chitin) called the radula.
• A mantle which is a fold in the body wall that lines the shell.
• Muscular foot (and/or tentacles in some).

What are two characteristics that mollusks and annelids share?

Annelids have other similarities with mollusks, including: A closed circulatory system (like cephalopods). An excretory system consisting of tubular nephridia. A complete digestive system.