All MCQs

Olfactory receptors are chemoreceptors that detect airborne molecules. They help animals locate food, mates, predators, and environmental signals.

The inner ear contains balance organs that detect head movement and position. Damage can disrupt equilibrium and coordination.

Cephalopods have large brains and advanced sensory systems for invertebrates. Their behavior includes learning, camouflage, and complex movement control.

Hormones affect only target cells that possess matching receptors. Receptor specificity explains why a circulating hormone does not act equally on every tissue.

Hormone action requires receptor binding. If receptor structure is altered, the target cell may fail to respond even when the hormone is present.

Taste and smell are chemosensory systems. They detect dissolved or airborne molecules and convert chemical information into neural signals.

Stretch receptors and proprioceptors give feedback about muscle length and body position. This information helps maintain coordinated movement.

Diffuse nerve nets spread signals through the body and support simple coordinated responses. They are common in cnidarians.

Endocrine glands are ductless and release hormones into blood or body fluid. Exocrine glands release secretions through ducts onto surfaces or into cavities.

Endocrine effects often develop more slowly and last longer than nerve impulses because hormones circulate and alter metabolic or gene-regulatory processes.

Proprioceptors detect muscle stretch, joint position, and body orientation. They help coordinate posture, balance, and movement.

Sensory neurons carry information from receptors toward the central nervous system. Motor neurons carry commands from the CNS to muscles or glands.