Introduction to Mollusks

The video tutorial introduces mollusks, a group of invertebrate animals within the phylum Mollusca, which includes about 110,000 species such as clams, mussels, oysters, scallops, and squid. Mollusks are characterized by their soft bodies and the presence of shells, which can be external or internal. Some mollusks, like clams and mussels, have two shells, while others, like snails, have a single shell. Slugs lack shells entirely. Cephalopods, a highly developed class of mollusks, have eyes and tentacles for capturing prey.

How many identified species of mollusks are there approximately?

• About 1,000

• About 10,000

• About 110,000

• About 1,100

Describe the characteristics of mollusks that do not possess shells.

• They are always small

• They can be found in water only

• They are called slugs

• They have a hard outer covering