Physiologic Lipids & Functions | Chapter 21 – Harper’s Illustrated Biochemistry (31st) скачать в хорошем качестве

Physiologic Lipids & Functions | Chapter 21 – Harper’s Illustrated Biochemistry (31st)

This chapter provides a comprehensive examination of lipids, a diverse category of biological molecules primarily characterized by their hydrophobicity and solubility in nonpolar solvents. It systematically classifies these substances into simple lipids like fats and waxes, complex lipids such as phospholipids and glycolipids, and derived lipids including steroids and free fatty acids. The text emphasizes the multi-faceted roles lipids play in human physiology, serving as a dense energy reservoir in adipose tissue, providing thermal insulation, and acting as electrical insulators for the rapid transmission of nerve impulses along myelinated fibers. A deep dive into fatty acid chemistry explains how chain length and the degree of unsaturation dictate melting points and membrane fluidity, while also distinguishing between naturally occurring cis isomers and health-damaging trans isomers found in processed foods. The discussion extends to eicosanoids, identifying them as crucial 20-carbon signaling molecules—including prostaglandins, thromboxanes, and leukotrienes—that regulate inflammation and various local hormonal responses. Furthermore, the chapter highlights the structural importance of amphipathic lipids in forming the lipid bilayer of cell membranes, micelles, and liposomes. Significant attention is given to cholesterol, detailing its role as the fundamental precursor for vital steroids such as bile acids, vitamin D, and various adrenocortical and sex hormones. Finally, the narrative addresses the clinical relevance of lipid peroxidation, a chain reaction involving initiation, propagation, and termination stages that produces harmful free radicals. This process is linked to tissue damage and chronic conditions like atherosclerosis, underscoring the vital protective function of both enzymatic and dietary antioxidants, such as vitamin E and vitamin C, in neutralizing reactive oxygen species. 📘 Read full blog summaries for every chapter: https://lastminutelecture.com 📘 Have a book recommendation? Submit your suggestion here: https://forms.gle/y7vQQ6WHoNgKeJmh8 Thank you for being a part of our little Last Minute Lecture family! ⚠️ Disclaimer: These summaries are created for educational and entertainment purposes only. They provide transformative commentary and paraphrased overviews to help students understand key ideas from the referenced textbooks. Last Minute Lecture is not affiliated with, sponsored by, or endorsed by any textbook publisher or author. All textbook titles, names, and cover images—when shown—are used under nominative fair use solely for identification of the work being discussed. Some portions of the writing and narration are generated with AI-assisted tools to enhance accessibility and consistency. While every effort has been made to ensure accuracy, these materials are intended to supplement—not replace—official course readings, lectures, or professional study resources. Always refer to the original textbook and instructor guidance for complete and authoritative information.