Question

Put the following parts of a reflex arc in the correct order beginning with the sensory receptor.
A. Motor neuron
B. Interneuron
C. Effector
D. Sensory neuron
E. Sensory receptor

• A. E, D, B, A, C
• B. E, D, A, B, C
• C. A, B, C, D, E
• D. A, E, D, B, C

Answer 1

The correct option is A E, D, B, A, C

Most reflex arcs have five main components which include receptors, sensory neurons, interneurons, motor neurons and effector organs like muscles.

Our body has certain epidermal cells with specialised parts called sensory receptors. These respond to stimuli in the environment like pressure, pain, vibrations, light etc., which lead to generation of impulses. These impulses then get transmitted to the spinal cord via the sensory neuron.
In the spinal cord, another type of neuron known as interneuron is present that receives the electrical signals.
Interneuron then relays the signal to the motor neuron. Motor neuron runs out of spinal cord and connect with the effector like muscle.
Thus, the correct sequence is a sensory receptor, sensory neuron, interneuron, motor neuron and effector.