Gastrointestinal Physiology Lab Practical PDF

GASTROINTESTINAL PHYSIOLOGY Title of Experiment: Investigative Studies on Salivary Secretion in Humans ATTENTION: READ EACH INSTRUCTION FIRST, AND UNDERSTAND THE BASIC CONCEPT OF THE TEST BEFORE YOU ATTEMPT TO PERFORM IT. PART A METHODS 1. Collection of...

GASTROINTESTINAL PHYSIOLOGY Title of Experiment: Investigative Studies on Salivary Secretion in Humans ATTENTION: READ EACH INSTRUCTION FIRST, AND UNDERSTAND THE BASIC CONCEPT OF THE TEST BEFORE YOU ATTEMPT TO PERFORM IT. PART A METHODS 1. Collection of Saliva for Basal Rate of Secretion (whole mouth collection) Swallow any saliva in your mouth and start the stop clock from now and do not swallow any saliva. Sit with your head resting on your hands so that the saliva accumulates near the front of the oral cavity. Every 2 minutes for 10 minutes expel all the saliva from your mouth into a measuring cylinder and take a reading after the addition of each sample. (Ignore any froth when taking a reading). Find the average resting rate of secretion of saliva in ml/minutes. II. The effect of Sodium Chloride: Place a small amount of solid sodium chloride on the surface of the tongue and repeat STEP I. III. The effect of Ascorbic acid (vitamin C) Place a small amount of concentrated Ascorbic acid on the surface of the tongue and repeat STEP I. IV. The effect of Chewing Meat Repeat STEP I after continuously chewing a piece of boiled meat for 5 minutes. V. The effect of Chewing Repeat STEP I while continuously chewing on a piece of tasteless chewing gum. VI. The effect of Chewing and Ascorbic Acid Determine the combined effect of chewing and Ascorbic acid together. Repeat step I PART B INVESTIGATING THE DIGESTIVE ACTION OF SALIVA (1) Place the piece of bread provided in your mouth and without chewing it, note its taste and record. (2) Now chew it for about 5-6 seconds and again note and record its taste. (3) Continue chewing it for as long as you like till it is ready for deglutition and just before you swallow please note and record the taste for the third time. Is there any difference between its taste during the three occasions? (4) Explain the findings noted in steps (1), (2) and (3). You may repeat the Entire experiment if you are not so sure you have recorded the actual tastes you sensed. Be precise. QUESTIONS: 1). What are the effects of different substances used on salivary secretion? 2). What is the difference between conditioned and unconditioned reflex secretion of saliva? 3). What is the effect of Salivary amylase on carbohydrate digestion? 4). List the functions of saliva