Reflex action immediately involves

Given below are different components of a reflex arc:
$I$. Effector organ
$II$. Interneuron
$III$. Motor neuron
$IV$. Sensory neuron
$V$. Sensory receptor
Arrange these in the correct order of the action potential that follows a sensory receptor stimulation.

What is reflex action?

The figure given below shows a reflex arc. Identify $P, Q,$ and $R$.

Which of the following is an incorrect relationship?

The path of a reflex action is: