Description: Segment 1 Dr Ian Gilliland introduces Professor David Smyth. Smyth begins with a joke about 'Smyth's Law' which states that if you think something is going to be easy either you'll be proved wrong or it will have been done before. He then explains how, in the 1940s, a new technique enabling the study of intestinal absorption was discovered, opening the way for many new experiments. The technique was one which produced a preparation of intestine which could show the act of absorbtion outside the body. Smyth refers to a diagram showing apparatus set up for observing the movements of intestinal muscle, then a diagram showing the absorptive function of the intestine. Time start: 00:00:00:00 Time end: 00:04:49:19 Length: 00:04:49:19 Segment 2 Smyth refers to experiments by Fisher and Parsons in which glucose was added to a section of intestine, thus demonstrating the intestine's capacity to transfer glucose. He then tells of an experiment by Dr Wiseman on the mucosal fluids of the intestinal wall he shows a diagram differentiating in vivo from in vitro experiments on the intestine. Smyth describes the 'everted sac' technique, an in vitro preparation discovered by Drs Wilson and Wiseman in 1954. This technique involves removing an animal's intestine under anaesthesia, then everting it on a glass rod. Once everted, small sacs can be made of the intestine, each one can be filled with different substances and intestinal absorption measured. Time start: 00:04:49:19 Time end: 00:09:14:00 Length: 00:04:25:06 Segment 3 Smyth shows how the above experiments relate directly to the physiology of absorption. He shows diagrams and graphs illustrating various intestinal absorption processes, then turns to show how the above techniques can be used to study them. He begins with absorption kinetics and outlines two types: absorption kinetics and saturation kinetics. Diffusion kinetics relates to the rate of absorption in proportion to the concentration of the substance absorbed. Saturation kinetics is the study of the limit of absorption, of the point where the intestine is so saturated as to be unable to absorb further. Time start: 00:09:14:00 Time end: 00:15:20:14 Length: 00:06:06:14 Segment 4 Smyth shows graphs listing the rates of absorption of different substances in the intestine, including proteins and carbohydrates. He also talks about the absorption of water-based substances, using diagrams to show how they pass through cell membranes. Time start: 00:15:20:14 Time end: 00:21:00:00 Length: 00:05:40:09 Segment 6 Smyth turns to look at the electrical activity of the intestine. He shows the results of an experiment measuring the absorption of sodium and fluid by the intestine when the intestine is artificially stimulated by different levels of electrical volt. He then discusses the relationship between various substances and different electrical volts, using diagrams and graphs to illustrate his points. Time start: 00:25:00:00 Time end: 00:30:11:00 Length: 00:05:11:00. Segment 7 Smyth differentiates two important functions of cells during intestinal absorption: transfer and metabolism. Transfer is, he says, an energy requiring process while metabolism is an energy donating process. Smyth shows a diagram illustrating the passage through the intestine of energy user and energy donor substances. He then focuses specifically on the transfer and metabolism of galactose and shows a table listing different substances which affect galactose transfer. Time start: 00:30:11:00 Time end: 00:34:25:00 Length: 00:04:14:00. Segment 8 Smyth refers to an experiment by Diamond in which mannitol, a substance which the intestine cannot absorb, was placed in the intestine to see if it acted as a barrier to substances which would normally be absorbed intestinally. Smyth sums up the lecture by looking forward to the 'few million experiments' which will no doubt follow the discovery of the new technique for measuring intestinal absorption that he outlined at the start of the lecture. Time start: 00:34:25:00 Time end: 00:40:20:21 Length: 00:05:55:21