Biology... Describe the pathway of reflex... 10 pts to most helpful answer!!?

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Darcie

New member
Describe the pathway of either the Ankle-Jerk Reflex, the Gag Reflex, or the PatellarReflex.

I've been trying to figure this out for the past 6 hours and I can't find the answer to any of the options... If anyone could help me out, I'd really appreciate it. This is my 2nd last assignment and then I'm done the course for good. Thanks in advance! :)
 
Striking the patellar tendon with a tendon hammer just below the patella stretches the quadriceps muscles in the thigh. This stimulates stretch sensory receptors (most importantly, muscle spindles) that trigger an afferent impulse in a sensory nerve fiber of the femoral nerve leading to the lumbar region of the spinal cord. There, the sensory neuron synapses directly with a motor neuron that conducts an efferent impulse to the quadriceps femoris muscle, triggering contraction. This contraction, coordinated with the relaxation of the antagonistic flexor hamstring muscle causes the leg to kick. This reflex helps maintain posture and balance, allowing one to walk without consciously thinking about each step.

The patellar reflex is a clinical and classic example of the monosynaptic reflex arc. There is no interneuron in the pathway leading to contraction of the quadriceps muscle. Instead the bipolar sensory neuron synapses directly on a motor neuron in the spinal cord. However, there is an inhibitory interneuron used to relax the antagonistic hamstring muscle.
 
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