Knee-jerk reflex, also called patellar reflex, sudden kicking movement of the lower leg in response to a sharp tap on the patellar tendon, which lies just below the.
A change in shape of a muscle (the stimulus) causes the muscle to readjust its shape (the response) and maintain your posture. • The knee-jerk reflex is base on.
For example, a tap to the tendon under the knee cap elicits (triggers) the "knee jerk" reflex. The diagram below shows how this reflex works.
The tendon below. The knee-jerk reflex is what's known as a mono-synaptic response, About This Image: Diagram of involuntary reflex action Within each body. The knee-jerk reflex is what's known as a mono-synaptic response, About This Image: Diagram of involuntary reflex action Within each body.The reflex arc governs the operation of reflexes.
Nerve impulses follow nerve pathways as they travel through the nervous system. The simplest of these pathways, including a few neurons. The familiar knee-jerk reflex, tested routinely by physicians, is a spinal reflex in which a brief, rapid tap on the knee excites muscle spindle afferent neurons, which then excite the motor neurons of the stretched muscle via a single synapse in the spinal cord.
1,5) However, the most striking symptoms are weakness of the quadriceps muscles and a decreased patellar reflex (3,5,7) which may result in difficulty ambulating. Weakness of the iliacus, quadriceps and sartorius muscles as well as the decreased patellar reflex supported this differential diagnosis. Reflex Arcs •In a knee-jerk reflex arc the sensory neuron directly connects to the motor neuron in the spinal cord.
This is called a simple reflex arc. • Follow the sensory neuron from the spindle (receptor) to where it connects with the motor neuron in the spinal cord.
• . Spinal Reflex Pathways. Monosynaptic Reflex.
The simplest reflex arc: the monosynaptic (stretch) reflex. This reflex is sometimes referred to as the stretch reflex, myotatic reflex or knee jerk reflex, because it is initiated by stretching the muscle.
Diagram of the paths of afferent neurones entering the spinal cord in the dorsal root.Knee-jerk reflex | medical test | schematron.orgPatellar reflex | definition of patellar reflex by Medical dictionary