BIOB34H3 Chapter ch 7: Lecture 3 Reading
19 Oct 2016
School
Department
Course
Professor
Document Summary
Energy metabolism process by which animals get energy, channel energy into useful functions. 2 subsets: catabolic breakdown organic molecules to release energy, anabolic use energy to construct molecules. Why animals need energy: the 2nd law of thermodynamics. Atoms composing an a(cid:374)i(cid:373)al"s body exchange with atoms in environment: atoms come and go, organization of atoms in body stays as it is. Law applies to isolated systems: exchanges nothing with surroundings. Order can be maintained or increased within a system if the system is not isolated. Energy = ability to do mechanical work: product of force and distance, energy is the capacity to increase order. Open system freely exchanges energy and matter with its surroundings: animals= open system in order to function. Need energy input for animals to work. W/o it animals become more disorganized and break down. 4 forms of energy: chemical energy. Atoms rearranged into new configuration: electrical energy. Separation of (+) and (-) electrical charges: mechanical energy.
