Maintenance of the Body
Unit 5: The Digestive System
Unit outline
Part 1: Overview of the Digestive System
- Digestive System Organs
- Histology of the Alimentary Canal
Part 2: Digestive System Processes and Regulation
- Digestive Processes
- Regulatory Mechanisms
Part 3: The Mouth, Pharynx, and Esophagus
- The Mouth
- The Pharynx
- The Esophagus
Part 4: The Stomach
- Struture
- Digestive Functions of the Stomach
Part 5: The Small and Large Intestines
- The Small Intestine
- The Large Intestine
- Absorption, Feces Formation, and Defecation
Part 6: Accessory Organs in Digestion: The Liver, Pancreas, and Gallbladder
- The Liver
- The Pancreas
- The Gallbladder
Part 7: Chemical Digestion and Absorption: A Closer Look
- Carbohydrate Digestion
- Protein Digestion
- Lipid Digestion
- Nucleic Acid Digestion
- Absorption
Learning Objectives
At the end of this unit, you should be able to:
I. Describe the major functions of the digestive system.
II. Describe the relationship between the following processes in the gastrointestinal system: ingestion, digestion, absorption, defecation.
III. Distinguish between extracellular digestion and intracellular digestion.
IV. Describe the anatomy of the buccal cavity and explain its functions in digestion.
V. Describe the process of deglutition (swallowing), explaining why food, when swallowed, does not enter the respiratory tract or the nasal cavity.
VI. Describe the anatomy and functions of the esophagus.
VII. Describe the anatomy and functions of the stomach.
VIII. Describe the liver with reference to: anatomy, function, connection to the duodenum and gallbladder, blood supply.
IX. Describe the anatomy and functions of the pancreas.
X. Describe the anatomy and functions of the small intestine.
XI. Describe the anatomy and functions of the large intestine.
XII. Describe the process of defecation
XIII. Describe the chemical digestion of the following, specifying the source and the function of the principal enzymes involved: carbohydrates, proteins, lipids, nucleic acids.
XIV. Specify the end-products of the digestion of the following and explain how they are absorbed: carbohydrates, proteins, lipids, nucleic acids.
XV. Describe the control of the secretion of digestive juices in humans in terms of: nervous control, hormonal control.
Learning Objectives and Guiding Questions
At the end of this unit, you should be able to complete all the following tasks, including answering the guiding questions associated with each task.
I. Describe the major functions of the digestive system.
- Describe the six major processes occurring during digestive system activity, and list all the organs of the gastrointestinal tract that perform each one.
II. Describe the relationship between the following processes in the gastrointestinal system: ingestion, digestion, absorption, defecation.
- Clearly define each of the following terms as they relate to the gastrointestinal system:
- Ingestion
- Digestion
- Absorption
- Defecation
III. Distin