Question : What is reflex action ? How is reflex arc formed ?

1.	Question : What is reflex action ? How is reflex arc formed ?
Answer» Solution :We experience sudden withdrawal of a body part which comes in contact with objects that are extremely hot, cold, pointed, animals that are scary or poisonous. The entire process of RESPONSE to a peripheral nervous stimulation that occurs involuntarily, without conscious efforts or thought and requires the INVOLVEMENT of a part of the central nervous SYSTEM is called a reflex action. The reflex pathway comprises one afferent neuron Receptor and one efferent (effector) neuron appropriately arranged in a series. The afferent neuron receives signal from a sensory organ and transmits the impulse via a dorsal nerve root into the CNS at the LEVEL of SPINAL cord. The afferent neuron then carries signals from CNS to the effector. The stimulus and response, thus forms a reflex arc as shown in figure in the knee jerk reflex.

Discussion