kinetic energy is energy of motion; potential energy is stored energy; chemical energy is potential energy contained in chemical bonds of organic compounds; mechanical energy is type of kinetic energy
First Law of Thermodynamics
Law of conservation of energy; Energy cannot be created or destroyed; Energy can be changed from one form to another form
Second Law of Thermodynamics
when energy changed from one form to another, there is loss of usable energy; energy transformation increases entropy of the universeEntropy is measure of disorder or randomness
what increases When glucose (more organized) is broken down into CO2 + H2O
Entropy, potential energy decreases and one less stable compound is changed into two smaller stable compounds
ALL living organisms dependent on outside source of energy from
the sun
Metabolic Reactions and Energy Transformations
Cellular metabolism
sum of all chemical reactions that occur in cellCatabolism (breaking down) and Anabolism (building up)
Free energy
amount of energy available to do work
Exergonic reaction
releases energy
Endergonic reaction
requires energy
ATP (Adenosine Triphosphate):
is carrier of energy in cells
what is common energy currency for all cells; composed of Adenine + Ribose (pentose sugar) + 3 phosphate groups
ATP
Exergonic reaction
produces ATP
Endergonic reaction
requires ATP to proceed
Functions of ATP
chemical work; transport work; mechanical work
Metabolic Pathways and Enzymes
Metabolic pathway
is series of linked reactions
Enzyme
is a biological catalyst that speeds up chemical reaction
Enzymes usually proteins
participates in reaction but is NOT used up by reaction
Enzymes are highly specific
they increase rate of a reaction
Reactants in enzymatic reaction are
Substrates of the reaction
Energy of Activation
amount of energy that reactants must absorb before reaction will start
what decrease's amount of energy required before chemical reaction proceeds
Enzymes
Function of enzymes
active site of enzyme forms complex with substrate