BS Zoology Semester Exam MCQs

Inflammation increases blood flow and vessel permeability, allowing immune cells and molecules to reach the site. This helps contain pathogens and begin repair.

Stomach acid kills many swallowed microbes and is a chemical innate defense. It acts nonspecifically before pathogens enter tissues.

Amphibian skin is thin, moist, and richly supplied with blood vessels, making cutaneous gas exchange possible. Fish rely mainly on gills, while frog skin can supplement respiration.

In arthropods, the exoskeleton forms the body wall and provides internal attachment points for muscles. This arrangement allows jointed appendage movement and body support.

Comparative skeletons show adaptations for swimming, jumping, flying, or running. Form-and-function analysis explains why skeletons differ among fish, amphibians, birds, and mammals.

Closing the shell protects soft molluscan tissues from predators and drying. The behavior depends on adductor muscles and the protective shell.

Sensory neurons carry information from receptors toward the central nervous system. Damage prevents normal sensory signals from reaching processing centers.

The lateral line detects water displacement produced by nearby animals. It helps schooling fishes maintain spacing and direction when vision is limited.

Exercise increases the need for oxygen and nutrients in muscles. Increased capillary perfusion improves exchange and waste removal.

Tissue injury triggers inflammatory responses that recruit immune cells and defensive molecules to contain pathogens and begin repair.

Intact skin is a major barrier to pathogen entry. Cuts allow microbes to bypass this first line of defense.

Veins have thin walls and large lumens, allowing them to store much of the blood volume. They operate at low pressure.