Arco reflejo

The video tutorial explains reflex actions using the knee-jerk reflex as an example. It describes the simplest reflex arc, which consists of three neurons: a sensory neuron, an interneuron, and a motor neuron. The motor neuron triggers a muscle reaction without involving the brain, resulting in a faster response.

What role does the motor neuron play in a reflex action?

Why is the reaction in a reflex arc faster than passing through the brain?