Reflex Arc (Short Answer)
Dr.A.P.Ganesan
Komarapalayam
Explain the reflex arc with the help of a diagram
Definition
Reflex action is a sudden involuntary response to a sensory stimulus without mediation of higher centres.
It is mediated by the centres in the spinal cord
Reflex Arc
In the reflex action, many structures involve in the accomblishment of a reflex.
These structure are together called reflex arc.
It consists of a receptior , the afferent limb , the reflex centre , the connector fibres , the efferent limb and the effector organ.
1. Afferent limb
It consists of
A.Receptor : When it is stimulated ,impulses are formed .
B.Afferent nerve fiber : It tranmists the impulses to the reflex centre .
2.Reflex centre
It consists of
nerve cells where sensory impulses are converted into motor impulses .
3.Efferent limb :
It is made of
A. Motor or efferent nerve fibre : it transmits motor impulses to the organ
B.Effector organ : this may be muscle or gland which show the response
Applied Physiology
Knee jerk : Patellar tendon reflex.
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