During the contraction phase of a muscle twitch,
A. the action potential travels down the T tubule.
B. actin-myosin cross-bridges form.
C. acetylcholine stimulates the pre-synaptic terminal.
D. Ca2+ are transported back to the sarcoplasmic reticulum.
E. Na+ diffuse into the muscle fiber.
Answer: B
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Blood pressure is determined by
A) measuring the size of the pulse pressure. B) measuring the force exerted by blood in a vessel. C) measuring the degree of turbulence in a closed vessel. D) measuring the pressure in the left ventricle. E) All of the answers are correct.
Why are the effects of the sympathetic division more widespread than those of the parasympathetic division of the ANS?
Fill in the blank(s) with the appropriate word(s).
You are assessing a patient who sustained blunt trauma to the center of his back. He is conscious, but is unable to feel or move his lower extremities. His blood pressure is 80/50 mm Hg, pulse is 40 beats/min and weak, and respirations are 24 breaths/min and shallow. If IV fluids do not adequately improve perfusion, you should:
A) give 0.5 mg of atropine and consider a dopamine infusion. B) administer 1 mg of epinephrine 1:10,000 via rapid IV push. C) apply the pneumatic antishock garment and inflate all sections. D) administer a corticosteroid to reduce spinal cord inflammation.
The coronary sinus drains the ________ into the ________
A) coronary arteries; left ventricle B) cardiac veins; right atrium C) interventricular artery; left ventricle D) right atrium; right ventricle E) cardiac vein; right ventricle