Ch 8 study guide Flashcards
*Give cellular examples of potential and kinetic energy
POTENTIAL = Chemical energy & free energy
*potential energy stored in the bonds connecting atoms in molecules
*A raised weight., Water that is behind a dam, A car that is parked at the top of a hill
KINETIC = Heat & Light
*A speeding bullet, a walking person, and the rapid movement of molecules in the air
Define and understand the 2 laws of thermodynamics
The first law, also known as Law of Conservation of Energy, states that energy cannot be created or destroyed in an isolated system. The second law of thermodynamics states that the entropy of any isolated system always increases.
Catabolic pathway
Release energy by breaking down complex molecules to simpiler compounds
Anabolic pathway
Consume energy to build complicated molecules from simplier ones
Synthesis pathway
Anabolic
breakdown pathway
Catabolic
kinetic energy
Energy which a body possesses by virtue of being in motion.
potential energy
The energy held by an object because of its position relative to other objects
What is the difference between exergonic and endergonic reactions?
Exergonic reactions release energy; endergonic reactions absorb it In exergonic reaction the free energy of the products is lower than that of the reactants; meanwhile in endergonic the free energy of the products is higher than that of the reactants. … Most chemical reactions are reversible
What is the free energy of reactants vs products
The standard free energy change (∆Gº’) of a chemical reaction is the amount of energy released in the conversion of reactants to products under standard conditions.
What type of cellular reactions require energy to take place?
Metabolism is all the chemical reaction that take place in a living organism.
Where is the potential energy stored in an ATP molecule?
Energy is stored in the covalent bonds between phosphates, with the greatest amount of energy (approximately 7 kcal/mole) in the bond between the second and third phosphate groups.
Why is an investment of activation energy necessary to initiate a spontaneous reaction?
Molecules are stable. In order to be reactive, they must be unstable. Therefore, energy must be added to molecule in order for them to reach the transition state where their bonds can be broken.
What effect do enzymes have on activation energy and free energy wtihin a reaction?
enzymes lower the activation energy for chemical reactions. Enzymes decrease the Gibbs free energy of activation, but they have no effect on the free energy of reaction. Enzymes work by lowering the activation energy ( Ea or ΔG✳ ) for a reaction. This increases the reaction rate. The free energy of the product is the same as it would be without the enzyme.
What does it mean “Enzymes are highly specific?”
Enzymes are highly selective catalysts, meaning that each enzyme only speeds up a specific reaction. ..