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What set of body parts does every mollusk have?

What set of body parts does every mollusk have?

The mollusk body can generally be divided into three regions: the head, the foot, and a cluster of internal organs called the visceral mass.

What are 3 structures that all molluscs possess?

All mollusks have a visceral mass, a mantle, and a foot. The visceral mass contains the digestive, excretory, and reproductive organs. The mantle is a covering. It may secrete a shell.

Which kinds of mollusks have a head?

Cephalopods. Cephalopods include the octopus and squid. They have a prominent head and a well-developed brain.

What type of body does all mollusk have?

Molluscs are a clade of organisms that all have soft bodies which typically have a “head” and a “foot” region. Often their bodies are covered by a hard exoskeleton, as in the shells of snails and clams or the plates of chitons.

Which body part is not typically found in mollusks?

Mollusks do not have fully developed lungs. Instead, aquatic mollusks breathe through gills, and land mollusks have membranes that operate like primitive lungs. Extending from the visceral mass is a protective tissue fold known as the mantle.

Does Mollusca have body cavity?

Both flatworms and molluscs are triploblastic, bilaterally symmetric, and cephalized. But molluscs have developed a true coelom, an internal body cavity enclosed by mesodermal membranes. The coelom in molluscs, however, is strangely reduced to a small space around the heart, sometimes called a hemocoel.

What are 3 characteristics of mollusks?

Characteristic Features of Phylum Mollusca

  • They are bilaterally symmetrical.
  • They are triploblastic, which three layers.
  • They show organ system grade of organisation.
  • The body is soft and unsegmented.
  • Body is divisible into three regions – head, a visceral mass, and ventral foot.
  • Body is covered by a mantle and shell.

What is the most intelligent group of mollusk?

Intelligence of squid and octopuses. The cephalopod class of mollusks are considered the most intelligent invertebrates and an important example of advanced cognitive evolution amongst animals in general.

Do mollusks have organs?

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. The excretory system of mollusks is made up of tubular organs called nephridia that filter waste from internal body fluids.

What type of body cavity do starfish have?

symmetry: radial, sometimes combined with bilateral. type of gut: blind sac with very reduced anus, or complete with anus. type of body cavity other than gut: coelom.

Why is Snail a Mollusca?

The Class Gastropoda (in Phylum Mollusca) includes the groups pertaining to snails and slugs. The majority of gastropods have a single, usually spirally, coiled shell into which the body can be withdrawn. The shell of these creatures is often what is recovered in a fossil dig.

What are 5 characteristics of mollusks?