CHAPTERS 24 AND 25

THE DIGESTIVE SYSTEM AND METABOLISM

STUDY OBJECTIVES

· State the overall function of the digestive system.

· Name the organs of the gastrointestinal tract. Name the accessory digestive organs.

· Define ingestion. Describe peristalsis. State the function and processes of mechanical digestion. Describe segmentation. Define chemical digestion, absorption and defecation.

· Describe the location and function of the visceral peritoneum, parietal peritoneum, and mesentery (figure 24.30 will also be of assistance). Define peritonitis.

· Describe the location of each of the four layers of the GI tract wall. Describe the histology of the epithelium. State the function of the mucus produced by the epithelium.

· State the function of saliva. Define mumps.

· State the location, components, and function of pulp. State the common name and cause of dental caries. Define gingivitis and periodontal disease. Relate periodontal disease to tooth loss in adults.

· Explain the cause of heartburn.

· State the source and function of salivary amylase. State if the mouth, pharynx and esophagus have any role in absorption. Define mastication and deglutition. To the depth covered in lecture, describe the events that occur during deglutition and the propulsion of the bolus to the stomach.

· Define chyme. State the location and function of the lesser and greater omentum. State the name for the stomach's secretions. Name the digestive organ that produces intrinsic factor. State the functions of the following components of gastric juice: hydrochloric acid, pepsin, and intrinsic factor.

· Know that the mucus that clings to the stomach wall shields it from the damaging effects of gastric juice. Explain why pepsin does not digest proteins that are part of your stomach's wall.

· To the depth covered in lecture, describe the role of the stomach in mechanical digestion, chemical digestion and absorption. Explain how action of the trilayered muscularis externa produces chyme.

· Explain how absorption by the small intestine is assisted by plicae circulares, villi and microvilli. State the location of brush border enzymes.

· Define hepatitis and cirrhosis. State the digestive function of bile. Define gallstones.

· Define appendicitis and peritonitis (also see page 892). Explain how appendicitis and peritonitis are related.

· Describe the digestive and absorptive function of the large intestine.

· Describe the mechanism involved in defecation. Briefly describe diarrhea and constipation.

· Name the building blocks that are produced from the chemical digestive break down of carbohydrates. State where the chemical digestion of starch begins.

· Name the building blocks that are produced from the chemical digestive break down of proteins and lipids.

· State the function of the following components of pancreatic juice: sodium bicarbonate, pancreatic amylase, lipase, trypsin and chymotrypsin. State the function of brush border enzymes.

· Explain the role of bile in fat emulsification.

· State the organ of the GI tract where each of the following perform their function: gastric juice, pancreatic juice, bile, and brush border enzymes.

· To the depth covered in lecture, describe how the end products of carbohydrate, protein and fat digestion are absorbed. Describe how water is absorbed.

· Relate old age to bowel movement frequency and constipation, periodontal disease and GI tract cancer.

· From chapter 25, define nutrient and vitamin. State their overall function and contrast this function with that of other organic nutrients.

· Identify the following and state their digestive system function. You do not need to state the function of structures signified by *.

oral cavity

lips

cheeks

gingivae*

hard palate

soft palate

uvula*

tongue

papillae

salivary glands

parotid glands*

submandibular glands*

sublingual glands*

dentitions*

incisors

canines

premolars

molars

tooth structure*

crown*

root*

enamel

dentin*

pulp cavity*

root canal*

cementum

pharynx

esophagus

stomach

cardia*

fundus*

body*

pylorus*

pyloric sphincter

lesser curvature*

greater curvature*

rugae

longitudinal muscle layer

circular muscle layer

oblique muscle layer

small intestine

duodenum*

jejunum*

ileum*

mucosa

villi

epithelium

lamina propria

muscularis mucosa

capillaries*

lacteal*

submucosa

blood vessels*

lymphatic vessel*

plicae circulares

muscularis externa

circular layer*

longitudinal layer*

serosa

liver

right lobe*

left lobe*

common hepatic duct

gallbladder

cystic duct

bile duct

pancreas

pancreatic duct

hepatopancreatic ampulla*

large intestine

cecum*

appendix*

ascending colon*

transverse colon*

descending colon*

sigmoid colon*

rectum*

anus