BCM 475 Chapter Notes - Chapter 22: Adipose Tissue, Subcutaneous Tissue, Intestinal Epithelium
Document Summary
Amphipathic: long hydrocarbon chain with terminal carboxylate group. 4 physiological roles: fuel molecules: stored as triacylglycerols (triglycerides/neutral fats) Uncharged esters of fatty acids with glycerol. Fatty acids can be oxidized to meet energy needs (primary energy source during moderate exercise/rest: building blocks of phospholipids and glycolipids. Important components of biological membranes: covalent attachment of fatty acids to proteins = modification. Targets proteins to membrane locations: serve as hormones/intracellular messengers. Complete oxidation = 38 kj g- due to being very reduced and anhydrous. Anhydrous fat stores ~7x times more energy as hydrated glycogen. Glucose/glycogen stores provide enough energy to sustain physiological function for ~24hrs, but triacylglycerol stores = survival for weeks. Located throughout the body; under skin (subcutaneous fat) and surrounding organs (visceral fat) Droplets coalesce to form large globule = lipid droplet: surrounded by monolayer of phospholipids/proteins. Also stored in muscle: used for its own energy needs. Adipose tissues: specialized for synthesis/storage of triacylglycerols + mobilization into fuel molecules.
