Test: Arthropoda, Mollusca & Echinodermata - JAMB MCQ

Phylum Arthropoda is characterized by jointed appendages and a segmented body. The jointed appendages allow for a wide range of movements, and the segmented body provides flexibility. Examples of arthropods include insects, spiders, and crustaceans.

Phylum Arthropoda includes organisms such as spiders, insects, and crustaceans. Arthropods are the largest phylum in the animal kingdom and exhibit a wide range of diversity in terms of species and habitats.

Phylum Echinodermata exhibits a radially symmetrical body plan, which means their body parts are arranged in a circular pattern. They also possess a unique water vascular system, a network of fluid-filled canals and tube feet, which they use for locomotion and feeding. Examples of echinoderms include starfish, sea urchins, and sea cucumbers.

Phylum Mollusca includes organisms such as snails, clams, and octopuses. Mollusks typically have a soft body protected by a hard shell. They also possess a muscular foot for locomotion, a mantle that secretes the shell, and a radula, a specialized feeding structure.

Phylum Arthropoda exhibits a hard exoskeleton made of a tough polysaccharide called chitin. Arthropods molt their exoskeletons as they grow, and their bodies are divided into segments. These segmented bodies provide flexibility and facilitate specialized functions in different body regions.

Phylum Mollusca includes organisms with a foot, mantle, and radula. The foot is a muscular structure used for locomotion, the mantle is a fold of tissue that secretes the shell (if present), and the radula is a specialized feeding structure used for scraping or drilling food. Examples of mollusks include snails, clams, and squids.

Starfish, sea urchins, and sea cucumbers belong to Phylum Echinodermata. Echinoderms have a spiny skin and exhibit a radial symmetry in their body plan. They also possess a water vascular system, which aids in locomotion, gas exchange, and capturing food particles.

The exoskeleton of arthropods, such as insects and crustaceans, is primarily composed of a tough polysaccharide called chitin. Chitin provides rigidity and protection to the arthropod's body while allowing for flexibility at the joints.

Cephalopods, such as octopuses and squids, belong to the class Cephalopoda within Phylum Mollusca. Cephalopods are known for their well-developed sensory organs, ability to change color and shape, and complex behaviors.

Phylum Echinodermata possesses a water vascular system, a network of fluid-filled canals and tube feet. This system enables echinoderms to move, capture prey, and exchange gases. The water vascular system is unique to echinoderms and is not found in other phyla like Arthropoda or Mollusca.