GI Physiology Practice Questions and Answers 2023

GI Physiology Practice Questions and Answers 2023 True In western cultures it is considered inappropriate to discuss "the bowels" in normal conversation. As a result, epressions in the English language that contain references to gastrointestinal anatomy or function are generally considered offensive. True False True Cutting the head off a chicken and using the movement of its intestines to predict the future is poor science but it does demonstrate that the intestine can function in the absence of the brain. True False True The water component of saliva is necessary so that substances on the tongue can actually be tasted. True False E Which of the following is not a function of the gastrointestinal tract? a. Motility b. Secretion c. Digestion d. Absorption e. Regulation of metabolism E If a person was unable to produce saliva as a result of a disease process, they would have problems with all of the following EXCEPT: a. Tasting food b. Halitosis (bad breath) c. Talking d. Swallowing e. Digesting lipids (fats) D Saliva is hypotonic with respect to plasma at all flow rates whereas, pancreatic juice is isotonic. This is because: a. Secretion of pancreatic juice is stimulated by a larger number of endogenous compounds b. There is no reabsorption of Na+ and Cl- in the salivary ducts c. Salivary secretion is facilitated by myoepithelial cells d. In the pancreatic ducts there is free movement of water with ions e. Free ions are more easily bound to proteins in saliva C Salivation is under the control of the autonomic nervous system. Which of the following statements about this innervation is correct? a. Parasympathetic nervous stimulation decreases the rate of salivary secretion b. Sympathetic nerve stimulation decreases the rate of salivary flow c. Sympathetic and parasympathetic nerve stimulation both increase the rate of salivary flow d. Sympathetic and parasympathetic nerves have opposite effects on salivary flow e. The salivary glands receive only parasympathetic innervation B In both saliva and pancreatic juice there is one ion whose concentration is essentially constant at all flow rates. That ion is: a. Na+ b. K+ c. Cl- d. HCO3- e. All ions in saliva and pancreatic juice increase significantly at high flow rates D Which of the following statements about the ionic concentration of saliva is true? a. It is governed by the rapid absorption of water in the ducts of the salivon b. It varies in response to different types of food c. It is independent of flow rate d. It increases as the flow rate increases e. It increases as the flow rate decreases E Following a stimulated salivary secretion which of the following statements best describes the ionic composition of saliva as the flow rate decreases? a. The ions in saliva are present in relatively constant amount regardless of flow rate b. The potassium concentration decreases c. Sodium and potassium concentrations both decrease d. The concentrations of all ions are decreased e. The chloride concentration decreases C A mother brings her 4 year old son to the E.R. saying that he appears unwell and listless. When a few drops of lemon juice are placed on his tongue the boy holds his cheeks and begins to cry. Given this information your diagnosis would most likely be: a. Sjogren's syndrome b. Rubella c. Mumps d. Achaliasia e. Scleroderma D Anxious parents brings their 3 year old son to see you and say that he has exhibited a general malaise and that when they tried to get him to eat an orange he complained of discomfort, cried and stroked the sides of his face. Based on only this information your preliminary diagnosis would be that this child probably has: a. Chicken pox b. Tonsillitis c. Rubella d. Mumps e. Sjogren's disease E Which of the following diseases is often associated with a decreased salivary secretion? a. Allergic rhinitis b. "strep" throat c. Pernicious anemia d. Crohn's disease e. Mumps D During the normal process of swallowing, food is prevented from entering the nasal passages by: a. The tongue b. The epiglottis c. The glottis d. The uvula e. The negative intra-thoracic pressure B When we refer to the "intrinsic nerves" of the gut we mean: a. The vagus nerves b. The enteric nervous system c. Preganglionic parasympathetic nerves d. Postganglionic sympathetic nerves e. All autonomic innervations of the intestine D In the small and large intestine the function of neurons of the submucosal plexus (Meissner's plexus) is: a. The control of circular muscle relaxation b. Coordination of the peristaltic reflex c. To control the amplitude of slow waves d. Modulation of epithelial function e. To mediate intestine-intestinal reflexes A Throughout the intestinal tract the nervous structure that lies between the longitudinal and circular muscle layers is called: a. The myenteric plexus b. The submucosal plexus c. The mucosa d. The brush border e. The enterocyte C Action potentials in gastrointestinal smooth muscle are primarily mediated by the inward movement of which ion? a. Na+ b. K+ c. Ca+ d. Mg++ e. None of the above E In general, the relationship between electrical and mechanical activity in gastrointestinal smooth muscle may be summarized as: a. Bigger action potentials produce bigger contractions b. 1 slow wave = 1 contraction c. All slow waves result in action potentials, therefore, slow waves produce action potentials d. Slow waves, action potentials, and contractions are unrelated phenomena e. Large contractions correspond to large numbers of action potentials E The magnitude (duration and amplitude) of contraction of gastrointestinal smooth muscle is: a. Directly proportional to the number of slow waves b. Inversely related to the number of muscle action potentials c. Proportional to the amplitude of muscle action potentials d. Unrelated to electrical events e. None of the above