METABOLISMVOCABULARY
5 BIG CONCEPTS The Basis of metabolism Forms of Energy Laws of Energy Transformation Structure , Function, and Hydrolysis of AT
P Enzymatic Effects on Reactions
The BASIS Metabolism Metabolic pathway Anabolic pathway (biosynthetic pathways) Catabolic pathways (breakdown pathways) Bioenergetics Energy Kinetic Energy Heat Energy Potential Energy Chemical Energy
Forms of Energy Energy
Kinetic energy Heat, or thermal, energy
Potential energy Chemical energy
Law of Energy Transformation Thermodynamics First law of thermodynamics Entropy- a measure of disorder, or
randomness Second law of thermodynamics Spontaneous
Free Energy Free energy Equilibrium- Exergonic reaction Endergonic reaction
ATP Chemical work- Transport work- Mechanical work Energy coupling- ATP ATP Cycle Phosphorylated
Enzymes speed up metabolic reactions by lowering energy barriers
Enzyme Catalyst Activation e
nergy Transition s
tate Substrate Enzyme- su
bstrate complex
Active site Induced fit Cofactors Coenzyme Competitiv
e inhibitors
Noncompetitive inhibitors
Allosteric regulation
Cooperativity
Feedback inhibition
Metabolism the totality of an organism’s chemical
reactions We want increase our metabolism to lose
more weight
Metabolic Pathwaysa series of chemical reactions that either builds a complex molecule (anabolic
pathway) or breaks down a complex molecule into simpler compounds (catabolic pathway)
Anabolic Pathway(biosynthetic pathways) - metabolic pathway that
consumes energy to build complicated molecules from simpler ones
Bioenergeticsthe study of how energy flows through living organisms
Catabolic Pathway(breakdown pathways)- metabolic pathway that releases
energy by breaking down complex molecules into simpler compounds.
Energythe capacity to cause change
Kinetic Energy energy that can be associated with the relative motion of objects
Diver gains kinetic energy when he gains velocity
Heat Energy kinetic energy associated with the random
movement of atoms or molecules
Potential Energy energy that matter possesses because of its location or
structure As height increases, potential energy increases.
When diving off a diving board, all of the initial energy is potential.
Chemical Energy potential energy available for release in a
chemical reaction.
Thermodynamics the study of the energy transformations
that occur in a collection of matter
First Law of Thermodynamics
(principle of conservation of energy)- energy is transferred and transformed, but it cannot be created or destroyed.
Second Law of Thermodynamics
every energy transfer or transformation increases the entropy of the universe
Spontaneous a process that can occur without an input
of energy
Free Energy the portion of a system’s energy than can perform work when
temperature and pressure are uniform throughout the system, as in a living cell
∆G=∆H-T∆S ∆G=Gfinal state- Ginitial state
Equilibrium a state of maximum stability
ReactionsEXERGONIC ENDERGONIC a spontaneous chemical
reaction, in which there is a net release of free energy
a non-spontaneous chemical reaction, in which free energy is absorbed from the surroundings
Energy Coupling the use of an exergonic process to drive
an endergonic one
Types of workCHEMICAL TRANSPORT pushing of
endergonic reactions which would not occur spontaneously
pumping of substances across membranes against the direction of spontaneous movement
Mechanical beating of cilia, contraction of muscle cells, movement of chromosomes during cellular respiration
ATP (adenosine triphosphate)- an adenine-containing nucleoside
triphosphate that releases free energy when its phosphate bonds are hydrolyzed; used to drive endergonic reactions in cells
ATP Cycle
Phosphorylated referring to a molecule that is covalently
bound to a phosphate group
Enzyme (the cry) a macromolecule that acts as a catalyst http://
upload.wikimedia.org/wikipedia/commons/a/ae/GLO1_Homo_sapiens_small_fast.gif
Catalyst (your crying) a chemical agent that speeds up a
reaction without being consumed by the reaction
Activation Energy(free energy of activation)- the energy required to contort the reactant molecules so the bonds can break
Transition State when the reactants are in an unstable
condition
Substrate (hugged) the reactant an enzyme acts on
Enzyme-Substrate Complex (the hug)
– a temporary complex formed when an enzyme binds to its substrate molecule (s).
Active Site (hugger) a restricted region of the enzyme molecule that binds to the
substrate; I’m the hugger (active site) and you’re being hugged (substrate)
Induced Fit (hug you real tight) induced by entry of the substrate, the change in shape of the
active site of an enzyme so that it binds more snugly to the substrate
Cofactors (arms) any nonprotein molecule or ion that is required for the proper
functioning of an enzyme. Can be permanently bound to the active site or may bind loosely with the substrate during catalysis.
Coenzyme an organic molecule serving as a
cofactor. Most vitamins function as coenzymes in metabolic reactions.
http://www.youtube.com/watch?v=AYgdGqk8buQ
Competitive Inhibitor a substance that reduces the activity of an enzyme by entering
the active site in place of the substrate whose structure it mimics.
Noncompetitive Inhibitor a substance that reduces the activity of an enzyme by binding to
a location remote from the active site, changing the enzyme’s shape so that the active site no longer functions effectively.
Allosteric Regulation the binding of a regulatory molecule to a protein at one site that
affects the function of the protein at a different site.
Cooperativity a kind of allosteric regulation whereby a shape change in one
subunit of a protein caused by substrate binding is transmitted to all the others, facilitating binding of subsequent substrate molecules.
Feedback Inhibition a method of metabolic control in which the end
product of a metabolic pathway acts as an inhibitor of an enzyme within that pathway.