What is the body structure of a gastropod?
The gastropod body consists of four main parts: visceral hump, mantle, head, and foot. The body is attached to the shell either by one columellar muscle or by a series of muscles.
What is the columellar Muscle & why is it important?
The columellar muscles are contracted when the animal needs to withdraw the foot, head, and other soft parts into the shell for protection from drying out, and from predators. During these contractions the operculum and shell are approximated, and the animal is withdrawn within the latter.
What are the characteristics of gastropods?
Most gastropods have a single, usually spirally coiled shell into which the body can be withdrawn, but the shell is lost or reduced some important groups. Gastropods are characterized by “torsion,” a process that results in the rotation of the visceral mass and mantle on the foot.
Why is it called a gastropod?
Snails and slugs are known as gastropods, which mean ‘stomach foot’. This describes the way in which the body and internal organs of slugs and snails has been twisted back so that the stomach lies above the large fleshy foot of these animals.
What is the body of a snail called?
Gastropod shell
The gastropod shell is an animal shell which is part of the body of a gastropod or snail. It is an external skeleton or exoskeleton, which serves not only for muscle attachment, but also for protection from predators and from mechanical damage.
Why do snails have antennae?
antennae—the long projections from a snail’s head, for detecting scents and orientation, and sometimes having eyespots. Also known as tentacles. anterior—the front or head. apertural—within the shell opening for the snail’s body.
What are the functions of the Columellar muscle?
function in gastropods The columellar (shell) muscles of gastropods pull the foot and other parts of the body into the shell. The adductor muscles of bivalves (Figure 4) shorten to close the shell or relax to allow the shell to spring open, enabling the mollusk to extend its foot…
What is the Columela?
The columella is the most anteroinferior portion of the nasal septum and forms the central fleshy portion between the two nostrils when looking at someone’s nose. It is a single midline structure composed of cartilage and overlying skin, extending posteriorly from the tip of the nose.
Which is a unique feature of a gastropod?
Ans- The unique feature of the gastropod’s anatomy is that the body contains the head, mantle, and visceral hump. The mantle is responsible for the secretion of the calcium shell of the body, the mantle cavity also contains all the important life systems like the respiratory, reproductive, and digestive systems. Q2.
What kind of sea snail is a Turritella?
Turritella is a genus of medium-sized sea snails with an operculum, marine gastropod mollusks in the family Turritellidae.
How many species of gastropods are there on Earth?
Gastropoda is among the few class of organisms that can flourish in all three types of habitat, the three habitats are terrestrial region, marine water system, and freshwater ecosystem. There are about 65000 species of gastropod living on the planet.
Where did the name Gastropoda come from and why?
The name “Gastropoda” comes from the Greek roots “gastro” (= stomach) and “pod” (= foot). Snails were given this name because many have the appearance of crawling around on their stomachs. The foot of a cowrie (Cypraeidae) is visible as it crawls on a pane of aquarium glass. Photograph by Jonathan R. Hendricks.