Final answer:
A reflex arc is a neural pathway that enables a reflex action and includes five main components in sequence: the sensory receptor, sensory neuron, integration center, motor neuron, and the effector, which is the muscle or gland cell responding to the impulse.
Step-by-step explanation:
Components of a Reflex Arc
A reflex arc is the neural pathway that mediates a reflex action. In the correct sequence, the components of a generic reflex arc are:
- Sensory receptor: Detects the stimulus.
- Sensory neuron: Transmits the afferent impulse to the CNS.
- Integration center: Processes the information in the CNS, which could be as simple as a single synapse between a sensory neuron and a motor neuron (monosynaptic reflex), or it may involve one or more interneurons (polysynaptic reflex).
- Motor neuron: Conveys the efferent impulse from the integration center to the effector.
- Effector: Muscle or gland cell that responds to the efferent impulse by contracting or secreting a product.
The reflex arc allows for rapid, involuntary responses to stimuli, which help maintain homeostasis and protect the body from harm.
Reflex arcs can be somatic, controlling skeletal muscle, or autonomic, controlling internal organ functions.