PHSI 208 Lecture Notes - Lecture 55: Oxidative Phosphorylation, Adipocyte, Basal Metabolic Rate
Document Summary
The gi system does not regulate intake so therefore rely on behavioural mechanisms. Feeding state: some of the absorbed nutrients will be used immediately while most of it undergoes anabolism and gets stored. Anabolism = the synthesis of complex molecules from simpler ones together with the storage of energy. Fasting state: stored molecules are used for energy (catabolism) Intake > expenditure obesity (more stored than used) Intake < expenditure starvation (and a decrease in body weight) Brain areas involved in hunger and satiety (old view): Lateral hypothalamus = hunger center (desire to intake food) Ventromedial hypothalamus = satiety center (reduced desire to intake food) Brain areas involved in hunger and satiety (new view): Nts (nucleus tractus solitarii) in the medulla. Behavioural mechanisms function to maintain body weight at relatively stable value. Long term regulation of feeding behaviour: glucostatic theory glucose metabolism in the hypothalamus regulates food intake, lipostatic theory signals from the bodies fat stores regulate food intake.
