Introduction and Broad Objectives
The major objective of this sequence is for the students to obtain integrated information regarding the structure and function of the digestive system through lectures, laboratory exercises and small group conferences. More specific objectives, and expected learning outcome for each lecture and lab in the subtopic areas, will be provided in each session or may be found in lecture handouts or in the sequence syllabus.
In essence, the sequence will cover four major topic areas related to digestion;
- gross anatomical and histological structures of the digestive system
- actual processes of digestive function and its regulations
- metabolic interactions
- pharmacology of drug absorption and metabolism
The Structure and Function of the Digestive System
For this aspect of the sequence, a tightly-coordinated, multidisciplinary approach, involving embryology, anatomy, histology and physiology, is taken to illustrate:
- the formation and development of the GI tract
- the structural characteristics of the major anatomical subdivisions of the GI tract and their associated glands
- the functions of these structural subdivisions in the process of digestion
- the neural and hormonal mechanisms that regulate the activities of the digestive system
Included in these topic areas is the importance of the role of major digestive glands, namely, the salivary glands, pancreas, and liver in the process of digestion.
The liver represents the central site for metabolic regulation and control in addition to being a digestive gland, as it secretes bile. The liver is situated strategically to process nutrients absorbed by the intestine and serves as the major site for metabolic interaction. A series of lectures pertaining to the metabolism of carbohydrates, lipids and cholesterol will be presented.
Since most drug therapy is oral, the gastrointestinal tract plays a crucial role in pharmacokinetics. Diseases of the gastrointestinal tract may alter drug absorption and recirculation. The pharmacology lectures are designed to provide the student with an introduction to the basic principles that govern drug absorption and metabolism. It will be discussed also how metabolism and disposition of drugs cause certain drug-drug interactions and drug toxicity.
In addition to the subject matters listed above, there will be three lectures on nutrition; two Macro-nutrition and one Micro-nutrition lectures. Also, there will be one lecture on the interactions between the microbial flora of the GI tract and the host organism. Finally, there will be a patient-present MDC session dealing with “Intestinal malabsorption and cystic fibrosis” and clinical lectures dealing with “Gastrointestinal cancer-surgical considerations,” “Hernias,” and “Abdominal Radiology.”
Two textbooks are recommended to supplement Dr. Williams’ physiology lectures in this sequence:
Gastrointestinal Physiology, by Kim E. Barrett, published by Lange (McGraw Hill) 2006.
Gastrointestinal Physiology, 7th edition, by Leonard R. Johnson, published by Mosby, 2007.
Both should be viewed as supplementary and the lectures will not follow them directly but they cover the material. They are both paperbacks. No additional textbook is required for this sequence, other than those books that you were required to purchase for Fall Term.
Small Group Discussion
This session will provide you with an opportunity to discuss case studies of gastrointestinal physiology. Attendance at small group discussions is required and specific student room assignments are made by the Office of Medical Education. Failure to attend for any reason will require you to submit written answers to the small group discussion questions to the Sequence Coordinator.
Sequence Examination and Grading
Performance will be assessed by two quizzes and a comprehensive final examination. The quizzes over the weekend and will be all done online and will be made up of multiple choice type questions. The final exam will include both written and gross anatomy practical examinations. The gross anatomy practical examination will be done in gross anatomy laboratories.
The number of exam questions, as usual, will be approximately proportional to the time allocated for lectures and laboratory hours. All exam questions weigh equally and are worth 1 point. To pass the sequence, students must achieve a minimum score of 75% on the quiz and final exam, and fulfill the requirements of the physiology small group.
Failure to Attend the MDC or Small Group Sessions
In the GI sequence there are two required experiences (in addition to FCE Small Groups). In the RARE circumstance where a student cannot attend, the student must contact their class counselor in advance (or as soon as possible in an emergency) to request a deferral. (Please do NOT contact sequence directors with requests for or explanations of deferrals.) Absences will be approved or denied by class counselors based on the same guidelines used for Quiz and Exam deferrals. Should you obtain a deferral from your class counselor, make up instructions for the required experiences (found below) should be followed.
For the Required Patient Presentation, the remediation will be watching the video and a 2-page response paper describing the patient presentation.
For the Physiology Small Groups, the remediation will be writing answers to the small group question.