MCAT DIGESTIVE SYSTEM-24 QUESTIONS AND ANSWERS

alimentary canal one-way system that begins at the mouth and ends at the anus mechanical digestion physically breaks the food into smaller pieces Brainpower Read More 0:02 / 0:15 chemical digestion breaks the chemical bonds in food molecules stomach digests via enzymes and HCl (secreted by parietal cells); mucus membrane secreted by mucus cells protect epithelium from damage small intestine responsible for bulk of chemical digestion and nutrient absorption pancreatic juice contains bicarbonate that helps neutralize acidic chyme after it leaves the stomach and enzymes that can digest all three classes of food molecules (carbohydrates/proteins/fats) bile emulsifies fats to allow proper digestion and absorption vitamins fat-soluble (A, D, E, K) or water-soluble; absorbed in small intestine large intestine consists of cecum, colon, and rectum; absorbs water and salts Which of the following associations between the type of gastric cell or gland and its secretions is correct? A) mucus cell - HCl B) chief cell - pepsinogen C) parietal cell - mucus D) pyloric gland - gastric juice B) chief cell - pepsinogen Which of the following is NOT part of the small intestine? A) Ileum B) Cecum C) Jejunum D) Duodenum B) Cecum In an experiment, enterokinase secretion was blocked. As a direct result, levels of all of the following enzymes were affected EXCEPT A) trypsin B) aminopeptidase C) chymotrypsin D) carboxypeptidase B) aminopeptidase Which of the following INCORRECTLY pairs the digestive hormone with its function? A) Trypsin - hydrolyzes specific peptide bonds B) Lactase - hydrolyzes lactose to glucose and galactose C) Pancreatic amylase - hydrolyzes starch to maltose D) Lipase - emulsifies fats Lipase - emulsifies fats Where are proteins digested? A) Mouth and stomach B) Stomach and large intestine C) Stomach and small intestine D) Small and large intestines C) Stomach and small intestine Which of the following choices INCORRECTLY pairs a digestive enzyme with its site of secretion? A) sucrase - salivary glands B) carboxypeptidase - pancreas C) trypsin - pancreas D) lactase - intestinal glands A) sucrase - salivary glands You are looking at a CT scan of the abdomen of a child who presented to you with various symptoms, including projectile vomiting. You notice a constriction in the digestive system that prevents food from reaching the small intestine. Which structure is the most likely site of the problem? A) Cardiac sphincter B) Pyloric sphincter C) Cecum D) Rectum B) Pyloric sphincter All of the following processes occur in the mouth EXCEPT A) moistening of food B) bolus formation C) chemical digestion of starch D) chemical digestion of proteins D) chemical digestion of proteins Which of the following choices correctly identifies the course that a piece of bread takes through the digestive tract? A) mouth→trachea→esophagus→cardiac sphincter→stomach→pyloric sphincter→small intestine→large intestine→rectum→anus B) mouth→pharynx→esophagus→cardiac sphincter→stomach→pyloric sphincter→small intestine→large intestine→rectum→anus C) mouth→pharynx→esophagus→pyloric sphincter→stomach→cardiac sphincter→small intestine→large intestine→rectum→anus D) mouth→pharynx→esophagus→pyloric sphincter→stomach→cardiac sphincter→small intestine→large intestine→anus→rectum B) mouth→pharynx→esophagus→cardiac sphincter→stomach→pyloric sphincter→small intestine→large intestine→rectum→anus The epiglottis is to the trachea as the lower esophageal (cardiac) sphincter is to the A) stomach B) heart C) small intestine D) liver A) stomach Which of the following correctly pairs the nutrient with its site of absorption? A) chylomicrons - lacteals B) amino acids - large intestine C) vitamins A and E - stomach D) cholesterol - ascending colon A) chylomicrons - lacteals