NSC 310 Chapter 3 Objectives Study Exam Questions.

NSC 310 Chapter 3 Objectives Study Exam Questions. Explain how foods move through the digestive system, describing the actions of the organs, muscles, and digestive secretions along the way. - CORRECT ANSWER As figure 3.1 (pg71) shows, food enters the mouth and travels down the esophagus and through the upper and lower esophageal sphincters to the stomach, then through the pyloric sphincter to the small intestine, on through the ileocecal valve to the large intestine, past the appendix to the rectum, ending at the anus. The wavelike contractions of peristalsis and the periodic squeezing of segmentation keep things moving at a reasonable pace. Along the way, secretions from the salivary glands, stomach, pancreas, liver (via gallbladder), and small intestine deliver fluids and digestive enzymes. Describe the anatomical details of the intestinal cells that facilitate nutrient absorption. - CORRECT ANSWER the many folds and villi of the small intestine dramatically increase its surface area, facilitating nutrient absorption. Nutrients pass through the cells of the villi and enter either the blood (if they ware water soluble or small fat fragments) or the lymph (if they are fat soluble). Explain how nutrients are routed in the circulatory systems from the GI tract into the body and identify which nutrients enter the blood directly and which much first enter the lymph. - CORRECT ANSWER Nutrients leaving the digestive system via the blood are routed directly to the liver before being transported to the body's cells. Those leaving via the lymphatic system (large fats and fat-soluble vitamins) eventually enter the vascular system but bypass the liver at first. Describe how bacteria, hormones, and nerves influence the health and activities of the GI tract. - CORRECT ANSWER A diverse and abundant bacteria population supports GI health. The regulation of GI processes depends on the coordinated efforts of the hormonal system and the nervous system. Together, digestion and absorption break down foods into nutrients for the body's use. TO function optimally, a healthy GI tract needs a balanced diet, adequate rest, and regular physical activity.