Chapter 6 Fill in the Blank
Coenzymes
Organic molecules that must be present for other enzymes to function.
What is one way to activate an enzyme.
Phosphorylation.
What are some examples of oxidation-reduction?
Photosynthesis and cellular respiration.
Chemical Energy
Potential energy in food.
A cell _____ which enzymes are present or active at any one time.
Regulates
Products
Substances that form as a result of a reaction.
Reactants
Substances that participate in a reaction.
Enzymes are named for their ______ and normally end in ______.
Substrates, "ase". ex: Lipid = Lipase , Urea = Urease, Maltose = Maltase, RNA = RNase (Ribonuclease).
Mechanical Work
Supplying the energy needed for muscle contraction.
What do the laws of thermodynamics explain?
That the flow of energy in ecosystems occurs in one direction; energy does not cycle.
Energy of Activation (Ea)
The energy that must be added to cause molecules to react with one another.
Enzyme Cofactors
The necessary ions or molecules that Enzymes require at the active site in order to work properly.
Energy Transformations
The process of changing one form of energy to another one.
Substrates
The reactants in an enzymatic reaction.
Allosteric site
The site to which the effector binds.
Active site
The small part of an enzyme where substrate molecules bind and undergo a chemical reaction.
What is the ultimate source of energy for ecosystems?
The sun.
In Energy Transformation there is always a loss of what?
Usable energy, usually as heat.
What is a type of Coenzyme?
Vitamins.
Mechanical Energy
What organisms convert chemical energy into for motion.
Enzyme Substrate Complex
What the enzyme and substrate form during the induced fit reaction.
Induced Fit
When the active site undergoes a slight change in shape in order to accommodate the substrates.
Enzyme inhibition
occurs when a molecule (the inhibitor) binds to an enzyme and decreases its activity.
Energy
the ability to do work.
Enzymes
A protein molecule that speeds a chemical reaction without itself being affected by the reaction.
Exergonic reactions
A reaction where energy is released. Has a negative DeltaG.
Another way to control enzyme activity is to _______ or ________ the enzyme.
Activate, deactivate.
Free energy G
The amount of energy to do work after a reaction has occurred.
ATP (Adenosine Triphosphate.)
The energy carrier between exergonic and endergonic reactions.
Metabolism
The sum of all the chemical reactions that occur in a cell.
What does "Free Energy" mean?
When the cell or the enzyme is able to do work. (ATP)
Catalyst
A substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change.
What is ATP constantly regenerated from after energy is expended by the cell?
ADP
Potential Energy
Stored Energy.
Feedback Inhibition
When the product of a metabolic pathway is in abundance, it binds competitively with the enzyme's active site.
Coupled Reactions
Where the free energy of a thermodynamically favorable reaction (ATP) is used to "drive" a thermodynamically unfavorable one, by joining the two reactions.
How is Free Energy (DeltaG) calculated?
By subtracting the free energy of reactants from that of products.
What are the three ways cells make use of ATP?
Chemical Work, Transport Work, and Mechanical Work.
What is the second law of thermodynamics?
Energy cannot be changed from one form to another without loss of usable energy.
What is the first law of thermodynamics?
Energy cannot be created or destroyed, but it can be changed from one form to another.
Kinetic Energy
Energy of motion.
What must be turned on or off to regulate the quantity of enzyme present?
Genes
Endergonic Reactions
Has a positive DeltaG and occurs only if there is an input of energy.
What are the advantages of the use of ATP by the cell?
It can be used in many types of reactions. When ATP ->ADP+P, energy released is sufficient for cellular needs and little energy is wasted. ATP is coupled to endergonic reactions in such a way that it minimizes energy loss.
What is Oxidation?
Leo the lion says GRRRRRRRR. (Losing electrons is oxidation. Gaining electrons is Reduction).
What is Reduction?
Leo the lion says GRRRRRRRR. (Losing electrons is oxidation. Gaining electrons is Reduction).
The addition of an enzyme does not change the free energy of the reaction, rather an enzyme ______ the energy of activation.
Lowers
Transport Work
Moving cells across cell membranes.
What is entropy?
A measure of disorder of a system.
Metabolic Pathway
A series of linked reactions.
Chemical Work
ATP supplies energy needed to synthesize macromolecules that the cell needs to exist.
Denatured
Any factor that alters the shape of an active site.
