Which of the following animals lack alimentary canal?

Explanation

The question is asking which animal does not have an alimentary canal. An alimentary canal is a digestive tube that runs from the mouth to the anus and is usually found in animals that have a complete digestive system. The options given are earthworm, jellyfish, insect, fish, and mollusks. An earthworm has an alimentary canal, so it cannot be the correct answer. A jellyfish also has an alimentary canal, so it is not the correct answer either. A fish and mollusks both have an alimentary canal as well, so they cannot be the correct answer. The correct answer is option C, insect. Insects lack an alimentary canal. Instead, they have a digestive system consisting of a foregut, midgut, and hindgut. The foregut is responsible for storing and grinding food, while the midgut is responsible for digesting and absorbing nutrients. The hindgut is responsible for absorbing water and eliminating waste. In summary, the animal that lacks an alimentary canal is an insect. It is important to know the different types of digestive systems found in animals to better understand their feeding habits and nutritional needs.