Correct Answer: B. Nereis as a polychaete representative
Explanation:
Nereis is a common polychaete annelid representative. Its parapodia and numerous setae make it useful for studying polychaete structure. This MCQ belongs to the Annelida topic in Animal Diversity-I and is written to test concept understanding rather than memorized wording.
Complete metamorphosis, or holometabolous development, has four stages: egg, larva, pupa, and adult. Butterflies, beetles, flies, and bees show this pattern. This MCQ belongs to the Insecta topic in Animal Diversity-I and is written to test concept understanding rather than memorized wording.
Correct Answer: C. endoskeleton of calcareous ossicles
Explanation:
Echinoderms have an endoskeleton made of calcareous ossicles or plates. In sea urchins these plates form a rigid test. This MCQ belongs to the Echinodermata topic in Animal Diversity-I and is written to test concept understanding rather than memorized wording.
Leeches belong to Hirudinea. They often have anterior and posterior suckers, a reduced coelom, and no setae in the adult stage. This MCQ belongs to the Hirudinea topic in Animal Diversity-I and is written to test concept understanding rather than memorized wording.
Jointed appendages are a defining feature of arthropods. They allow efficient locomotion, feeding, sensing, reproduction, and many other specialized functions. This MCQ belongs to the Arthropoda topic in Animal Diversity-I and is written to test concept understanding rather than memorized wording.
Incomplete metamorphosis includes egg, nymph, and adult stages. Nymphs resemble adults but lack fully developed wings and reproductive organs. This MCQ belongs to the Insecta topic in Animal Diversity-I and is written to test concept understanding rather than memorized wording.
Sea stars belong to class Asteroidea. They have arms that are not sharply separated from the central disc and are common representatives of echinoderms. This MCQ belongs to the Asteroidea topic in Animal Diversity-I and is written to test concept understanding rather than memorized wording.
Cephalopods have a well-developed head, arms or tentacles, advanced eyes, and a complex nervous system. They are the most active molluscs. This MCQ belongs to the Cephalopoda topic in Animal Diversity-I and is written to test concept understanding rather than memorized wording.
Annelids generally have a closed circulatory system, where blood remains within vessels. This is more efficient than relying only on diffusion in larger active worms. This MCQ belongs to the Annelida topic in Animal Diversity-I and is written to test concept understanding rather than memorized wording.
Arthropods have a chitinous exoskeleton that protects the body and provides muscle attachment. Because it is rigid, growth requires periodic molting or ecdysis. This MCQ belongs to the Arthropoda topic in Animal Diversity-I and is written to test concept understanding rather than memorized wording.
Correct Answer: D. exoskeleton provides muscle attachment
Explanation:
The arthropod exoskeleton provides protection and points for muscle attachment. Muscles attach internally to the exoskeleton and move jointed appendages efficiently. This MCQ belongs to the Arthropoda topic in Animal Diversity-I and is written to test concept understanding rather than memorized wording.
Brittle stars belong to Ophiuroidea. Their long flexible arms are clearly distinct from the central disc and are used for movement. This MCQ belongs to the Ophiuroidea topic in Animal Diversity-I and is written to test concept understanding rather than memorized wording.