What is the foot of a mollusk?
In muscle: Mollusks. … highly muscular organ called the foot, through which muscle fibres run in all directions. The foot of a gastropod is a flat structure used for crawling. Waves of muscular contraction travel along its length, moving the animal slowly over the ground.
What is the function of the foot in mollusks?
Mollusks have a muscular foot, which is used for locomotion and anchorage, and varies in shape and function, depending on the type of mollusk under study. In shelled mollusks, this foot is usually the same size as the opening of the shell. The foot is a retractable as well as an extendable organ.
Which mollusk means head foot?
Their shells can easily be mistaken for gastropods, but cephalopod shells are chambered, having many internal partitions inside of their shells, while gastropod shells are unchambered. The name cephalopod, in Greek, means “head foot.” This name was applied because the foot of the organism is around the head.
What is the foot of a clam called?
Clams are marine mollusks with two valves or shells. Like all mollusks, a clam has a mantle which surrounds its soft body. It also has a muscular foot which enables the clam to burrow itself in mud or sand. The soft tissue above the foot is called the visceral mass and contains the clam’s body organs.
What are the three body parts of a mollusk?
In general, mollusks have 3 body regions: a head, a visceral mass, and a “foot.” The head contains the sense organs and “brain,” while the visceral mass contains the internal organs. The “foot” is the muscular lower part of the body which is in contact with the substrate.
What are three functions of a mollusks foot?
A mollusk’s muscular foot is used for locomotion and anchorage, varies in shape and function, and can both extend and retract. The visceral mass inside the mollusk includes digestive, nervous, excretory, reproductive, and respiratory systems.
What are the 3 types of mollusk?
The three major groups of mollusks are gastropods, bivalves, and cephalopods (SEF ul o pods). The largest group is the gastropods. These are mollusks like snails and slugs that have just one shell or no shell at all. Gastropods creep along on their broad foot.
Does a Mollusca have a shell?
mollusk, also spelled mollusc, any soft-bodied invertebrate of the phylum Mollusca, usually wholly or partly enclosed in a calcium carbonate shell secreted by a soft mantle covering the body.
What is the anatomy of a mollusk?
The generalized mollusc is bilaterally symmetrical and has a single, “limpet-like” shell on top. The shell is secreted by a mantle covering the upper surface. The underside consists of a single muscular “foot”. The visceral mass, or visceropallium, is the soft, nonmuscular metabolic region of the mollusc.
What is mantle in molluscs?
The mantle (also known by the Latin word pallium meaning mantle, robe or cloak, adjective pallial) is a significant part of the anatomy of molluscs: it is the dorsal body wall which covers the visceral mass and usually protrudes in the form of flaps well beyond the visceral mass itself.
What are the four basic parts of mollusk?
The four important body parts in the mollusk could be listed as: Shell, Mantle, Visceral Mass and Foot.
What are the main parts of a mollusk In addition please define them?
Some of the qualities that define a mollusk are definite organs (mainly heart, gonads, and kidneys), a complete digestive tract, and a muscular foot. Although their bodies are not segmented, they do have two definable parts: the head and the foot. Their shells are made of calcium carbonate.
What kind of shell does a hatchet footed mollusc have?
Bi means ‘two’ and as the name suggests these molluscs possess tow shells. They are also known as Pelecypoda meaning ‘hatchet-footed’. They are bilaterally symmetrical and show no torsion. Head is greatly reduced, no tentacles but have a foot that can often be seen sticking out of the valves.
What does the name head footed mollusc mean?
The name means ‘head-footed’, these are exclusively marine molluscs that have a prominent and large head, eyes and tentacles. The eyes of these molluscs are fascinating to study as also some of the mechanisms of camouflage developed by the cuttlefishes.
What does Scaphopoda stand for in marine molluscs?
Scaphopoda means ‘boat-footed’. This class includes marine molluscs that usually remain buried in snad. The worm-like animal is found within tusk shaped shells that are open at both ends. Thus they are commonly referred to as tusk shells.
When was malcahia changed to Mollusca by Pliny the Elder?
Malcahia was changed to Mollia and Ostacodermata to Testacea by Pliny (the Elder) who lived in the years 23-79AD; and finally Mollia was changed to Mollusca by Jonstonus during the 17 th C. It did not stop there.