Explore the intricacies of gastric secretion in this 47-minute lecture focusing on the intestinal phase. Delve into key concepts such as gastrin, peristaltic waves, parietal cells, and the role of secretin. Examine the functions of various endocrine cells, including K cells and their GIP receptors. Investigate the importance of chemoreceptors and the protective mucous barrier in the gastrointestinal system. Gain a comprehensive understanding of this crucial phase in the digestive process through clear explanations and detailed insights provided by Professor Zach Murphy.