Question

Select the correct sequence of events in a polysynaptic reflex response.

- receptors, afferent neuron, interneuron, efferent neuron, effector
- effectors, afferent neuron, interneuron, efferent neuron, receptors
- effectors, efferent neuron, interneuron, afferent neuron, receptors
- effectors, efferent neuron, afferent neuron, receptors

Answer 1

The correct sequence for a polysynaptic reflex response is receptors, afferent neuron, interneuron, efferent neuron, and effector, forming a reflex arc that operates without direct brain input.

Step-by-step explanation:

The correct sequence of events in a polysynaptic reflex response is: receptors, afferent neuron, interneuron, efferent neuron, effector. In this sequence, a sensory receptor responds to a sensation and sends a nerve impulse along a sensory nerve to the spinal cord. In the spinal cord, the message passes to an interneuron. From the interneuron, the impulse is relayed to a motor nerve via the efferent neuron, which then carries the impulse to a muscle, known as the effector, resulting in a muscular contraction. This sequence forms what is known as a reflex arc, which operates automatically without direct input from the brain.