Question

In cephalopod, like Sepia
A. Inner shell is found
B. Outer shell is found
C. A folder shell is found
D. Shell is absent

Answer 1

Sepia also known as cuttlefish that belong to the order Sepiida. They are aquatic organisms generally found in the north Atlantic sea. Cephalopods are a class of marine animals.

Complete answer: The class cephalopods contain marine animals having bilateral symmetry, a prominent head, and a foot in the form of arms and tentacles. The mouth is surrounded by tentacles that have bear-like jaws e.g. octopus, squid, and nautiluses. They are complex and motile organisms.
Sepia i.e. cuttlefish belongs to the family Mollusca and class Cephalopod that includes octopus, squid, and nautiluses. They have eight arms, large pupils, two tentacles furnished with denticulated suckers that will help them to capture the prey. They eat small molluscs, crabs, worms, etc. Predators that attack cuttlefish are dolphins, sharks, seals, etc. The cuttlefish has an internal shell also known as cuttlebone whose main function is to control the buoyancy (it is the upwards force exerted by liquid) and this is possible due to the presence of the gas-filled chambers present in the inner shell of the cuttlefish. This inner shell or cuttlebone is made up of calcium also known as calcareous.
Hence, the correct answer is option A.

Note: The circulatory system in the Cephalopod consists of some extra accessory hearts except in Nautilus. Nautilus has an outer shell, while others have internal shells or no shells. Some of the extinct species are Belemnite , Ammonites and Goniatites.