Question

Leech, Nereis, Scolopendra, prawn and scorpion all have segmented body organization, but still, they cannot be classified in one group. Which of the following is the correct basis for the classification of these organisms into different groups?

• A. Leech and Nereis belong to the phylum Annelida because they have metamerically segmented body.
• B. Scolopendra, prawn and scorpion belong to the phylum Arthropoda, as they possess jointed appendages.
• C. Leech, Nereis and Scolopendra belong to the phylum Annelida because they possess closed blood vascular system.
• D. Both A and B.

Answer 1

The correct option is D Both A and B.

Leech and Nereis belong to phylum Annelida because they have a metamerically segmented body, i.e., the body is divided into many segments internally by septa. Scolopendra, prawn, and scorpion belong to phylum Arthropoda because the body segment of these animals usually bears paired lateral and jointed legs or appendages.