Question

Which among the following is incorrect with respect to molluscs?

• A. All have a soft segmented body which is differentiated into head, foot and visceral mass
• B. The visceral mass is covered by a mantle
• C. Open type of blood vascular system is seen
• D. Molluscs are coelomates

Answer 1

The correct option is A All have a soft segmented body which is differentiated into head, foot and visceral mass

The statement given in option a is incorrect. Molluscs do not have a segmented body. Molluscs are soft-bodied animals that have a protective calcareous shell covered by a soft, spongy layer called the mantle. Mantle lies over the visceral hump also called the visceral mass. Molluscs have a body cavity lined by a mesoderm layer, hence they are coelomates. The circulatory system is open or lacks closed blood vessels.