Question

What is the fold of dorsal body wall covering the visceral mass in Mollusca known as?
A) Shell
B) Mantle
C) Operculum
D) None of the above

Answer 1

Hint:The second largest phylum of invertebrate animals is Mollusca. The members are known as Molluscs. Molluscs are highly diverse. Molluscs also live in freshwater and terrestrial habitats.

Complete answer:
>There are three most universal features of molluscs that are mantle, presence of radula and the structure of the nervous system.
>The mantle is defined as a layer of tissue that lies between the shell and body.
>Mantles are defined as part of molluscs. Mantle is the dorsal body wall which covers the visceral mass and protrudes in the form of flaps.
>The epidermis of the mantle produces calcium carbonate and conchiolin which creates a shell.
>The mantle cavity is formed by a mantle skirt, a double fold of mantle which encloses a water space.
>This mantle space has mollusc’s gills,anus, osphradium, nephridiopores and gonopores.
>The mantle cavity acts as a respiratory chamber in most of the molluscs.
>In some molluscs the mantle cavity is a brood chamber and in cephalopods it is a locomotory organ.
>The mantle is highly muscular
>The mollusc’s visceral mass which is internal organs including heart, stomach are enclosed by the mantle.
>There is a cavity between the mantle and body called a mantle cavity.

So the correct answer is Mantle.

Note:Some examples of molluscs are octopi, squid, snails and slugs. Molluscs are an important food source for modern humans. Molluscs have also been the sources of important luxury goods, pearls, sea silk. The mantle helps in respiration, waste disposal and sensory reception.