Draw a diagram of the cerebral motor cortex and descending input to spinal motor neurons. Voluntary suppression of the knee jerk reflex originates in the motor cortex, which can send inhibitory signals to the motor neurons. If the left motor cortex is active, is the left or right knee jerk reflex suppressed or are both suppressed? Explain your answer. If the left side of the spinal cord at the
level of leg muscle control is damaged, is it the left or right knee jerk reflex that is suppressed or are both suppressed?
What will be an ideal response?
The diagram should resemble Figure 13.11 in the chapter. The left motor cortex controls the right spinal motor neurons and therefore the right knee reflex. The left side of the spinal cord controls the reflex on the left side.
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A difference between mucous membranes and serous membranes is
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Afferent fibers from muscle spindle stretch receptors in a muscle make excitatory synaptic contact with motor neurons that innervate the extrafusal fibers of the same muscle
Indicate whether the statement is true or false.
Micturition involves both ________ and ________ nerve signals.
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