BIOLOGY 225 Lecture Notes - Lecture 36: Ice Crystals, Emperor Penguin, University Of Cape Town
Document Summary
Range of temperatures optimal for physiological processes; metabolic rate is minimal. Metabolic rate increases as animal induces a physiological response to prevent overheating. Metabolic rate increases to increase heat production. Animals differ in the width of their thermoneutral zone, uct, and lc. Animals have an optimum or preferred body temperature; this is the temperature at which physiological functions are optimal. Ectotherms choose microclimates that allow them to keep body temperature as close to preferred body temperature as possible. Move between shade and rock to keep body at optimal temperature. Metabolic compensation: changes in metabolic machinery that allow some ectotherms to maintain optimal metabolic rates at very different ambient temperatures (after acclimatization). Isozymes - enzymes with same catalytic function but different temperature optima. For example, different myosin isoforms in winter and summer. Physiological mechanisms allow ectotherms to control the rate of change in body temperature. Color change: by changing skin color can alter body reflectance - can increase or.
