What are the characteristics of the class cephalopoda?
All cephalopods have the same basic anatomy. They’re made up of a body, a head and a foot. They have a muscular casing called a mantle which contains and protects their organs. They all have arms — at least eight of them — that are attached directly to their heads, but only some species also have tentacles.
What unique features are exhibited by the animals in the class cephalopoda?
These exclusively marine animals are characterized by bilateral body symmetry, a prominent head, and a set of arms or tentacles (muscular hydrostats) modified from the рrimitive molluscan foot. Fishers sometimes call cephalopods “inkfish”, referring to their common ability to squirt ink.
What are some distinguishing features of cephalopods that are different from other mollusks?
The most obvious difference between most cephalopods and other mollusks is the apparent lack of a shell. Octopuses do not have shells at all, while squids have a small internal shell. (Nautiluses, which are found in the South Pacific and Indian oceans, are the only cephalopods with an external shell.
What does class cephalopoda include?
This class contains the cephalopods, animals commonly known as squid, cuttlefish, octopus, and nautilus. The giant squid is the largest of all mollusks. Most cephalopods are highly adapted for swimming. Members of the subclass Coleoidea (the squid, cuttlefish, and octopus), have an internal shell or no shell at all.
Which features of the squid are common to all members of the phylum Mollusca?
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.
Which is not a characteristic of cephalopoda?
Excretory system – Cephalopods possess a single pair of large nephridia which produce nitrogenous waste and excrete it out from the body. Therefore, from the above discussion it has been clear that Sea squirt is not a cephalopod.
Which is not characteristic of cephalopods?
What characteristics of Mollusca distinguish it from other phyla?
Mollusks all have a mantle, a shell secreted by the mantle, a visceral hump, a foot, and a radula. Mollusks are different from other phyla because they have these things, most of which are unique to the phylum Mollusca. Describe the valve of a clam. The valve of a clam is also known as each half of the clam’s shell.
What are the unique features of Mollusca?
Mollusca Characteristics
- They are mostly found in marine and freshwater.
- They exhibit organ system level of organization.
- Their body has a cavity.
- The body is divided into head, visceral mass, muscular foot and mantle.
- The head comprises of tentacles and compound eyes.
- The body is covered by a calcareous shell.
What do cephalopods eat?
Cephalopods are a class of fast-swimming mollusk. Some have a hard external shell, but most do not. Cephalopods are marine predators; these carnivores eat fish, worms, crustaceans, and other mollusks. Some cephalopods include the octopus, squid, cuttlefish, nautilus, and ammonite (and other extinct animals).
Do cephalopods have a foot?
All cephalopods have the same basic anatomy. They’re made up of a body, a head and a foot. They have a muscular casing called a mantle which contains and protects their organs.
Is a cephalopod a mollusk?
Cephalopods are a group of swimming mollusks, including the living squid, octopus, and the chambered Nautilus.
Are squids cephalopods?
Squid are cephalopods in the superorder Decapodiformes with elongated bodies, large eyes, eight arms and two tentacles. Like all other cephalopods, squid have a distinct head, bilateral symmetry, and a mantle.