Chapter 6- Metabolism: energy and enzymes Flashcards
What are the 6 forms of energy?
Chemical electrical radiant mechanical nuclear thermal
What is the branch of chemistry concerned with energy changes?
thermodynamics
what is the most convenient way of measuring energy?
heat
What is the first law of thermodynamics?
Energy cannot be created or destroyed
What is the 2nd law of thermodynamics?
entropy- some energy is always lost
Do cells have a lot or little entropy?
little b/c they are organized
What is a metabolic pathway?
A series of linked chemical reactions that occur in a cell
What are the reactants, products, and intermediates called?
metabolites
which reaction has more energy in the products than reactants, and requires energy input?
endergonic reaction
Which reaction releases energy and products have less energy?
exergonic reaction
What is a coupled reaction?
Exergonic reaction fuels endergonic reaction
Where is the energy in ATP stored?
The last phosphate bond
What is ATP composed of?
adenosine and 3 phosphates
energy is released when ATP is broken down into?
ADP + P
Almost all enzymes are what type of molecule?
protein
What do enzymes do?
Speed up reactions by lowering the amount of energy required to initiate a reaction
What is the active site?
pocket of enzyme where the substrate binds
What is the change in an enzyme from the substrate binding somewhere other than the active site called?
allosterism
What is allosteric inhibition?
Alosteric inhibitor binds and stabilizing enzyme, stopping it from forming products
What are oxidation reduction reactions?
energy-releasing electron transfers- one molecule gives up electrons and one gains them
Does oxidation occur when hydrogen is lost or gained?
Lost
Is reduction gaining or losing an electron?
gaining
