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?
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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A) A B) C C) D D) E E) B 1) Periosteum. 2) Articular cartilage. 3) Joint (articular) cavity. 4) Synovial membrane. 5) Fibrous layer.
Which are differences between cardiac muscle tissue and skeletal muscle tissue?a: The sarcoplasmic reticulum in cardiac muscle is less extensive.b: The sarcoplasmic reticulum in cardiac muscle is more organized.c: Cardiac muscle has intercalated discs; skeletal muscle does not.d: Cardiac muscle has 1 or 2 nuclei per cell; skeletal muscle has multiple nuclei per cell.e: Cardiac muscle has more well-defined terminal cisternae.
A. a, b, e B. a, c, d C. a, c, e D. b, c, e E. b, d, e
Which type of memory has the potential to last a lifetime?
A. Short term B. Immediate C. Long term D. None of these answers are correct
The inability to recall recent past events following a traumatic event is known as ____________________, whereas the inability to store new memories for later retrieval is called ____________________
Fill in the blank(s) with correct word