BI110 Lecture Notes - Lecture 9: Closed System, Kinetic Energy, Autotroph
Document Summary
Anaerobic heterotrophic organisms --> thought to be first organisms to have evolved on primitive earth. O2 in atmosphere comes from a type of photosynthesis that oxidizes water. Solar-powered sea slug: heterotrophic organism acquires ability to be autotrophic. Why it matters: life requires relatively cold temp. (below 100oc) Reactions occur quicker at these temp: enzymes speed up rates of chemical reactions. Life would not exist w/o enzymes since it would take a very long time in the temp. required for life to be sustained. Phosphatase enzymes remove phosphate groups from proteins in 10 ms. Uncatalyzed reaction would take 1 trillion years. Potential energy --> stored energy: energy can be converted from one form to another. Thermodynamics: study of energy and its transformations. Closed system --> exchanges energy but not matter w/ surroundings. Open system --> exchanges energy and matter w/ surroundings. Isolated system --> doesn"t exchange energy or matter w/ surroundings. Energy cannot be created or destroyed (conservation of energy)
