BioMedical Admissions Test (BMAT) 2025 – 400 Free Practice Questions to Pass the Exam

The sequence of events in a reflex action begins with a stimulus that is detected by sensory receptors. This detection initiates an impulse that travels along the sensory neurons to the spinal cord, where it synapses with relay neurons. The relay neurons then transmit the impulse to the motor neurons, which carry the signal to the muscles to elicit a response.

This process showcases the fundamental organization of the reflex arc, which is essential for quick, involuntary responses to stimuli. The pathway allows for efficient communication between sensory input and motor output, thereby enabling rapid reactions without the need for input from the brain, which is why reflex actions can be so quick.

Other choices do not accurately describe this sequence. For example, some suggest that impulses are sent directly to the brain or that sensory neurons communicate directly with muscles, both of which overlook the crucial role of relay neurons and the spinal cord in the reflex pathway. Thus, the understanding of option B encompasses the complete and correct pathway of reflex actions.