BS Zoology Semester Exam MCQs

An endoskeleton is internal, living tissue that grows with the body and provides strong support for larger animals. It also allows muscles to attach for controlled movement.

Arthropod muscles attach to the inner surfaces of the exoskeleton. Contraction moves jointed appendages, making the exoskeleton both protective and mechanical support.

A hydrostatic skeleton uses incompressible body fluid and muscle contractions to change body shape. Earthworms use circular and longitudinal muscles with coelomic fluid for burrowing locomotion.

The molluscan shell protects soft tissues and provides attachment points for muscles such as adductor muscles. It is not the main system for endocrine control or nerve conduction.

The vertebrate skeleton supports the body and works with muscles and fins to produce swimming movements. Its flexibility and segmental arrangement are linked to aquatic locomotion.

Jumping in frogs depends on strong hind limb muscles acting on skeletal levers. Bones and joints convert muscle contraction into powerful movement.

Bird skeletons contain lightweight adaptations while still providing rigid support. This combination helps flight by lowering mass without sacrificing wing control.

Calcium salts are important for mineralization and hardness of vertebrate bone. Poor mineral availability can weaken skeletal strength and normal support.

In many soft-bodied invertebrates, the integument protects the body and also allows cutaneous gas exchange when it remains moist. It is not only a covering; it contributes directly to physiological exchange with the environment.

Cilia are cell surface organelles that create movement or water currents by coordinated beating. This differs from movement produced by muscles pulling on skeletons.

Fish scales form a protective body covering and reduce drag during swimming. Their structure is related to protection and movement efficiency, not digestion, circulation, or immunity production.

Feathers are integumentary derivatives involved in flight, thermal insulation, waterproofing in many birds, and communication or display. They do not replace the skeleton or act as a blood-clotting system.