Search results
Results from the WOW.Com Content Network
The buccal mass is the first part of the digestive system, and consists of the mouth and pharynx. The mouth includes a radula, and in most cases, also a pair of jaws. The pharynx can be very large, especially in carnivorous species. Many carnivorous species have developed a proboscis, containing the oral cavity, radula, and part of the ...
The radula (US: / ˈ r æ dʒ ʊ l ə /; pl.: radulae or radulas) [1] is an anatomical structure used by mollusks for feeding, sometimes compared to a tongue. [2] It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food enters the esophagus .
Muscles that control the radula are shown in brown. The surface of the radula ribbon, with numerous teeth, is shown as a zig-zag line. The odontophore is part of the feeding mechanism in molluscs. It is the cartilage which underlies and supports the radula, a ribbon of teeth. [1] The radula is found in every class of molluscs except for the ...
Connective – A part connecting two other parts, as a muscle connecting two parts of the body, or a nerve connecting two ganglia. [1] Constricted – Narrowed. [1] Contractile – Capable of being contracted or drawn in, as the tentacle of a snail. [1] Convex – Bulged out, as the whorls of some snails. [1] Convoluted – Rolled together. [1]
Stylommatophora is the most diverse group of land snails and slugs. Pallial cavity forms a spacious, air-filled lung. Anus is located on the right side close to the pneumostome. Operculum is missing. Two pairs of tentacle are retractable and the posterior pair bears eyes on the tips. Radula typically has many small, quite uniform teeth per row.
Most authors figure the shells with the apex of the spire uppermost. In life, when the soft parts of these snail are retracted, in some groups the aperture of the shell is closed by using a horny or calcareous operculum, a door-like structure which is secreted by, and attached to, the upper surface of the posterior part of the foot. The ...
Haeckel (left), 1866 Sea snail shells, Kunstformen der Natur, 1904. Ernst Heinrich Philipp August Haeckel (February 16, 1834 – August 9, 1919), also written von Haeckel, was an eminent German biologist, naturalist, philosopher, physician, professor and artist who discovered, described and named thousands of new species, mapped a genealogical tree relating all life forms, and coined many ...
The anatomy of a common air-breathing land snail: much of this anatomy does not apply to gastropods in other clades or groups. Snails are distinguished by an anatomical process known as torsion, where the visceral mass of the animal rotates 180° to one side during development, such that the anus is situated more or less above the head. This ...