Chapter 6 Flashcards
Heat
-The random motion of molecules
Kinetic
- Energy of motion
- Mechanical
Potential
-stored energy
First Law
- Energy cannot be created or destroyed
* But it can be changed form one form to another
Second Law
-Energy cannot be changed from one form to another without a loss of usable energy
Entropy
-A measure of disorder or randomness
Cehmiosmosis
-Production of ATP due to a hydrogen ion gradient across a membrane
_______ ________-is the amount of energy available to perform work
Free energy
Exergonic Reactions
-Reactants have more free energy than products
Exergonic reactions
release energy
endergonic reactions
-require energy
In ________ __________ the energy released by an exergonic reactions drives an endergonic reaction
coupled reactions
Chemical work
-energy needed to synthesize macromolecules
Transport work
-energy needed to pump substances across plasma membrane
Enzymes are protein molecules that function as organic _________ to speed a chemical reaction
catalysts
- catalysts participate in the reaction
- is not changed by the reaction
The energy that must be added to cause molecules to react with one another is called the _______ ____ ___________
energy of activation
_______-the reactant that an enzyme changes
substrate
The _________ _____ fits to the substrate, and the enzyme changes shape slightly
active site
Enzymes are very specific to what substrates they bind to and what reaction they catalyze because of the __________ ____ ____ _____________
shape of the active site
Generally, enzyme activity increases as _________ _____________ increases
substrate concentration
As ___________ rises, enzyme activity increases
temperature
If temperature rises beyond a certain point, the enzyme becomes ___________ and the enzyme activity levels out
denatured
Enzymes also have an optimal ___
pH
Cells regulate which enzymes are __________ and/or ________
present;active
___________- inorganic ions and molecules
cofactors
*often metal ions like copper, zinc, iron
_________ __________-a non-protein molecule needed for an enzyme to be active:have the correct shape and properties of the active site
Enzyme cofactors
_____________-organic but not protein
coenzyme
__________-small organic molecules needed to make coenzymes
vitamins
*required only in trace amount
_______________- some enzymes are not activated until they have phosphate groups added to them in the proper place
Phosphorylation
Enzyme ___________- an active enzyme is prevented from combining with its substrate
inhibition
Feedback inhibition
-almost all enzymes are regulated in this way
Competitive Feedback inhibition
-the product of the enzyme binds to the active site of that enzyme
Regulation of entire metabolic pathways is most often accomplished by
Allosteric Feedback Inhibition
The inhibitor molecule binds to the enzyme at the ______ ______-a site that is not the active site
allosteric site
___________ is an inhibitor of cellular respiration
Cyanide
In ________ reactions, electrons pass from one molecule to another
redox
___________- the loss of electrons
oxidation
_____________- the gain of electrons
reduction
two major energy reaction pathways of life
- photosynthesis
- cellular respiration
Photosynthesis
carbon dioxide+ water + solar energy yields glucose and oxygen
Chloroplasts capture solar energy and convert it via ______ ___________ ______ to ATP
electron transport chain
Cellular Respiration
Glucose + oxygen yields carbon dioxide + water + energy
______________: Production of a ATP due to a hydrogen ion gradient across a membrane
Chemiosmosis
