Sometimes, when it is difficult to initiate a knee-jerk reflex by tapping the patellar tendon, a patient will be asked to voluntarily make a fist. Then the reflex will be easily evoked. What does this illustrate about the relation between voluntary and
involuntary reflex movement?
What will be an ideal response?
Descending motor tracts that excite the motor neurons that activate forearm and hand muscles also send excitatory impulses to motor neurons lower down the spinal cord. These EPSPs spatially summate with the excitatory inputs from the muscle spindles to quadriceps motor neurons, bringing the quadriceps neurons to threshold, and thus generate a brisk "knee jerk" response.
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The pancreas has both endocrine and exocrine functions.
Answer the following statement true (T) or false (F)
You turn your head to look at something. What type of joint movement is this?
A. Abduction B. Rotation C. Circumduction D. Retraction
Blood flows to the brain through the _____ arteries and away from the brain through the _____ vein
a) internal carotid and vertebral; internal jugular
b) external carotid and vertebral; external jugular
c) internal jugular and vertebral; internal carotid
d) internal carotid and axillary; internal jugular
e) external jugular and axillary; external jugular
Discuss the functions of the paranasal sinuses. Which bones contain paranasal sinuses?
What will be an ideal response?