【正文】 s is FALSE?[ ] A. The resting membrane potential of GI smooth muscle tends to be smaller in magnitude than that of skeletal muscle. B. Action potentials in GI smooth muscle are not blocked by tetrodotoxin. C. Longitudinal GI smooth muscle cells are less wellcoupled electrically than are circular smooth muscle cells. D. Slow waves are generated by GI smooth muscle cells near the inside of the circular muscle layer. E. Contraction of GI smooth muscle cells may occur in the absence of action potentials. 單項(xiàng)選擇題 (英 ) D 返回復(fù)習(xí)與思考 單項(xiàng)選擇題 (續(xù) ) 2. Which statement about gastrointestinal smooth muscle is NOT correct? [ ] A. The cells of the circular layer of gastrointestinal smooth muscle are coupled by numerous gap junctions. B. The lengthtension curve of gastrointestinal smooth muscle is broader than that of skeletal muscle C. In human stomach slow waves occur about 3 times per minute. D. Action potentials in gastrointestinal smooth muscle do not involve fast sodium channels. E. None of the above. E 返回復(fù)習(xí)與思考 3. Which of the following statements is NOT true? [ ] A. Gastrointestinal smooth muscle cells typically have smaller resting membrane potentials than skeletal muscle cells. B. The electrogenic character of the Na+,K+ATPase makes a small contribution to the resting membrane potential of GI smooth muscle cells. C. Slow waves elicit contraction of some GI smooth muscle even in the absence of action potentials. D. Many GI smooth muscle cells are electrically coupled to their neighbors. E. Action potentials in GI smooth muscle cells do not involve fast sodium channels. 單項(xiàng)選擇題 (續(xù) ) B 返回復(fù)習(xí)與思考 4. Which of the following statements about the innervation of gastrointestinal smooth musle is NOT true? [ ] A. There are no true neuromuscular junctions in gastrointestinal smooth muscle. B. The predominant innervation of the circular muscle layer is inhibitory. C. Most of the nerve fibers that innervate gastrointestinal smooth muscle cells have their cell bodies in the enteric ganglia. D. Most of the nerve fibers that innervate gastrointestinal smooth muscle cells are either cholinergic or adrenergic. E. Gastrointestinal smooth muscle is influenced by reflex arcs, all of whose ponents are located in the gastrointestinal. 單項(xiàng)選擇題 (續(xù) ) D 返回復(fù)習(xí)與思考 5. Which of the following statements about gastrointestinal smooth muscle is NOT true? [ ] A. Its lengthtension curve is broader than that of skeletal muscle. B. Cells of the circular layer have numerous gap junctions. C. Contractions are stronger when action potentials occur on the crests of the slow waves. D. Rhythmic oscillations of the resting membrane potential occur. E. Tone is due to a baseline level of spontaneous action potentials in the smooth muscle cells. 單項(xiàng)選擇題 (續(xù) ) E 返回復(fù)習(xí)與思考 6. Which of the following statements about gastrointestinal smooth muscle is NOT true? [ ] A. Slow waves occur at frequencies from 3 to 12 per minute. The frequency is characteristic of the various segments of the GI tract. B. Slow waves are generated by interstitial cells. Calcium channels contribute to the depolarizing phase of the slow waves. C. Circular muscle cells are well coupled electrically and have numerous gap junctions. D. Calcium that enters during an action potential participates in excitationcontraction coupling. E. Contractions do not occur in the absence of action potentials. 單項(xiàng)選擇題 (續(xù) ) E 返回復(fù)習(xí)與思考 試述消化道內(nèi)抑制胃酸分泌的主要因素及可能機(jī)制。 思考題 返回復(fù)習(xí)與思考 返回首頁 Thank You!