Reflex Arc

A reflex arc (synonyms: reflex pathway, reflex ring) is an anatomical structure that ensures the transmission of a signal from a receptor to an effector in response to a stimulus. Reflex arcs play an important role in regulating various body functions such as breathing, digestion, blood circulation, etc.

The reflex arc consists of the following components:

1. A receptor is the sensory part of a reflex arc that perceives a stimulus and converts it into an electrical signal. The receptors can be of various types such as mechanoreceptors, thermoreceptors, chemoreceptors, etc.
2. An afferent neuron is a nerve fiber that transmits a signal from a receptor to the central nervous system. Afferent neurons are often called sensory neurons.
3. Synapses are points of contact between neurons where electrical signal transmission occurs. Synapses can be excitatory or inhibitory, depending on what type of neuron they connect.
4. The central nervous system is the part of the reflex arc where information about the stimulus is processed. The central nervous system may include the spinal cord and brain, as well as other structures.
5. An efferent neuron is a nerve that transmits a signal from the central nervous system to an effector. Efferent neurons may also be called motor neurons or motor neurons.
6. An effector is an organ or tissue that performs a function in response to a signal from a reflex arc. Effectors can be different, for example, muscles, glands, blood vessels, etc.

Depending on the type of receptor and effector, reflex arcs can have a different structure.