Question

Which one of the following occurs without the help of brain?

• A. Cranial reflex
• B. Spinal reflex
• C. Efferent reflex
• D. Afferent reflex

Answer 1

Answer: (B)

Spinal reflex

1. Reflex arc transmits the sensory information from receptor to effector via autonomous nervous system (brain or spinal cord).
2. It consists of sensory receptor, afferent neuron, centre, efferent neuron and effector organ.
3. Spinal reflexes are the ones in which spinal cord serves as center without the involvement of the brain. The afferent/sensory neurons transmit the sensory information from sensory receptors to spinal cord; it constitutes the afferent/sensory pathway.
4. The interneurons of spinal cord integrate the incoming information and signal is relayed to motor/efferent neurons. The efferent/motor pathway transmits the signal from motor neurons to the effector organs (muscles and glands etc).
5. Thus, the correct answer is B.