Question

Adhesive zone of Dugesia is
A. Anterior
B. Posterior
C. Dorsal
D. Ventral

Answer 1

Hint: Dugesia belongs to the class Turbellaria and the phylum Platyhelminthes. Dugesia is also known as Planaria. Planaria is a bilaterally symmetrical genus with a flat body.

Complete answer: Dugesia has a bilaterally symmetrical, smooth, non-segmented body. There are no specialized organs and organ systems and they are flat and coelomate organisms. There are three layers present; they are the ectoderm, mesoderm and endoderm. Planarians live openly and are found in both freshwater and coastal waters. The ability to repair missing body parts is a special function of Dugesia. They have a single opening branched digestive tract. There are also associated structures, such as the mouth, pharynx and intestines. Breathing occurs by diffusion. The excretory cells are the flame cells. Sexual reproduction is observed in them. The locomotion is caused by beating or moving cilia. The body is bilaterally symmetrical. There are mainly free-living types. There are no holes found in the body of Dugesia. The ventral surface of Dugesia has an adhesive zone from which the glands form adhesive material. The adhesive zone clamps to the substrate itself. The mucus is secreted by mucosal glands opening on the ventral surface as the leaves are pulled behind the mucus trail.
Hence, option D is the correct answer.

Note: Dugesia has a soft body. They do not have a coelom, that is, acoelomate since they are devoid of respiratory and circulatory systems. Dugesia is also used in research laboratories for ageing because of its regenerative ability.