Question

How does a snail move​

Answer 1

Answer:

A land snail is any of the numerous species of snail that live on land, as opposed to the sea snails and freshwater snails. Land snail is the common name for terrestrial gastropod mollusks that have shells (those without shells are known as slugs). However, it is not always easy to say which species are terrestrial, because some are more or less amphibious between land and fresh water, and others are relatively amphibious between land and salt water.

Land snails are a polyphyletic group comprising at least ten independent evolutionary transitions to terrestrial life (the last common ancestor of all gastropods was marine). The majority of land snails are pulmonates that have a lung and breathe air. Most of the non-pulmonate land snails belong to lineages in the Caenogastropoda, and tend to have a gill and an operculum. The largest clade of land snails is the Cyclophoroidea, with more than 7,000 species.[6] Many of these operculate land snails live in habitats or microhabitats that are sometimes (or often) damp or wet, such as in moss.

Land snails have a strong muscular foot; they use mucus to enable them to crawl over rough surfaces and to keep their soft bodies from drying out. Like other mollusks, land snails have a mantle, and they have one or two pairs of tentacles on their head. Their internal anatomy includes a radula and a primitive brain. In terms of reproduction, many caenogastropod land snails (e.g., diplommatinids) are dioecious, but pulmonate land snails are hermaphrodites (they have a full set of organs of both sexes) and most lay clutches of eggs in the soil. Tiny snails hatch out of the egg with a small shell in place, and the shell grows spirally as the soft parts gradually increase in size. Most land snails have shells that are right-handed in their coiling.

A wide range of different vertebrate and invertebrate animals prey on land snails. They are used as food by humans in various cultures worldwide, and are raised on farms in some areas for use as food.

Answer 2

• Land snails move forward on a muscular foot covered with epithelial cilia and lubricated with mucus.
• Waves of muscle contractions flow down the ventral side of the foot, powering this motion.
• When a snail crawls over the glass of a window or an aquarium, its muscular activity is readily evident.
• Adult Helix lucorum snails travel at a proverbial snail's pace of 1 mm/s.
• To prevent their fragile bodies from drying out, snails exude mucus on the outside.
• They also exude mucus from their feet to facilitate movement by minimising friction and to help lessen the danger of mechanical harm from sharp surfaces, allowing them to crawl over a sharp edge such as a straight razor without injury.
• Land snails create a slime trail behind them because of the mucus they release with their feet.