Chapter- Principles of Bioenergetics
Chapter 14 Principles of Bioenergetics
1. Cells need energy to do all theirs work To generate and maintain its highly ordered structure(biosynthesis of macromolecules To generate all kinds of movement. To generate concentration and electrical gradients s across cell membranes.h To maintain a body temperature To generate light in some animals The energy industry(production, storage and use is central to the economy of the cell society!
1. Cells need energy to do all their work • To generate and maintain its highly ordered structure (biosynthesis of macromolecules). • To generate all kinds of movement. • To generate concentration and electrical gradients across cell membranes. • To maintain a body temperature. • To generate light in some animals. • The “energy industry”(production, storage and use) is central to the economy of the cell society!
the quantitative study of energy transductions in living cells and the chemical nature underlying these processes
• Bioenergetics (生物能学）: the quantitative study of energy transductions in living cells and the chemical nature underlying these processes
2. Cells have to use chemical energy to do all their work Antoine Lavoisier s insight on animal respiration in the 18th century: it is nothing but a slow combustion of carbon and hydrogen( the same nature as a lighting candle)5 Living cells are generally held at constant temperature and pressure: chemical energy(free energy) has to be used by living organisms, no thermal energy neither mechanical energy is available to do work in cells
2. Cells have to use chemical energy to do all their work • Antoine Lavoisier`s insight on animal respiration in the 18th century: it is nothing but a slow combustion of carbon and hydrogen (the same nature as a lighting candle). • Living cells are generally held at constant temperature and pressure: chemical energy (free energy) has to be used by living organisms, no thermal energy, neither mechanical energy is available to do work in cells
Biological energy transformation obey the two basic laws of thermodynamics revealed by physicists and chemists in the 19th century: energy can neither be created nor be destroyed(but conserved); energy conversion is never 100% efficient (some will always be wasted in increasing the disorder or entropy of the universe) The free energy concept of thermodynamic is more important to biochemists than to chemists (who can always increase the temperature and pressure to make a reaction to occur!)
• Biological energy transformation obey the two basic laws of thermodynamics revealed by physicists and chemists in the 19th century: energy can neither be created nor be destroyed (but conserved); energy conversion is never 100% efficient (some will always be wasted in increasing the disorder or “entropy” of the universe). • The free energy concept of thermodynamic is more important to biochemists than to chemists (who can always increase the temperature and pressure to make a reaction to occur!)