The body of the pond snail is enclosed in a spirally twisted shell with a sharp top and a large opening – the mouth. The shell protects the soft body of the pond snail.
The head, leg and front of the body can protrude through the shell opening. The entire abdominal side of the pond snail’s body is occupied by a muscular leg. The pond snail moves forward, sliding the sole of the foot along the bottom or near-water plants.
The body of the pond snail closely adheres to the shell, repeating its shape. In the front part, the body is covered by a skin fold – a mantle. The space between the body and the mantle constitutes the mantle cavity. In front, the torso passes into the head. A mouth is placed on its underside, and two sensitive tentacles on the sides. At their bases there is an eye
The digestive system of the pond snail begins with the mouth leading to the pharynx. It contains a muscular grater covered with teeth. The mollusk uses it to scrape off the soft parts of plants and algae that it feeds on. Respiratory system. The pond snail breathes oxygen in the air. Rising to the surface of the water, it opens a round respiratory opening, which leads to the pulmonary cavity.
The pond snail has an open circulatory system. It consists of the heart and blood vessels. From the heart, blood moves through the vessels, enters the cavities and washes the internal organs.
The excretory system of the pond snail includes one kidney with a ureter opening next to the anus. The nervous system is represented by a periopharyngeal accumulation of nerve nodes with nerves extending to all organs.
Reproduction. Pond snails are hermaphrodites. When mating pond snails, both partners mutually fertilize each other. The eggs are laid in the form of long, gelatinous cords.
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