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Muscle Knee Jerk Reflex Leg Neurone Flexor Describe Arc

The knee-jerk reflex is triggered by tapping the patellar tendon, causing the quadriceps to contract and the hamstrings to relax, resulting in leg extension. The sensory neuron directly connects to the motor neuron and, via an interneuron, inhibits the motor neuron to the flexor muscle.

El reflejo rotuliano se desencadena al golpear el tendón rotuliano, causando la contracción del cuádriceps y la relajación de los isquiotibiales, lo que resulta en la extensión de la pierna. La neurona sensorial se conecta directamente con la motora y, a través de una interneurona, inhibe a la neurona motora del músculo flexor.

Front Describe the knee-jerk reflex arc.
Back Knee-jerk reflex:
  • When leg tapped below kneecap, it stretches the patellar tendon & this acts as stimulus which initiates reflex arc that causes the extensor muscle on top of thigh to contract (sensory directly connected to motor)
  • At same time, relay neurone inhibits motor neurone of flexor muscle, causing it to relax
  • This contraction coordinated with relaxation of antagonistic flexor muscle causes leg to kick

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