There are two types of reflex arcs:the autonomic reflex arc, affecting inner organs, and the somatic reflex arc, affecting muscles. When a reflex arc consists of only two neurons, one sensory neuron, and one motor neuron, it is defined as monosynaptic. Monosynaptic refers to the presence of a single chemical synapse.
What are the essential components of a reflex arc?
Reflex arcs have five essential components:
- The receptor at the end of a sensory neuron reacts to a stimulus.
- The sensory neuron conducts nerve impulses along an afferent pathway towards the CNS.
- The integration center consists of one or more synapses in the CNS.
What makes up a reflex arc?
A motor neuron carries the message from the central nervous system to the effector. In a knee-jerk reflex arc the sensory neuron directly connects to the motor neuron in the spinal cord. This is called a simple reflex arc. from the spindle (receptor) to where it connects with the motor neuron in the spinal cord.