Chapter 7 Flashcards
Energy
The capacity to cause change
Kinetic energy
The energy of motion
Potential energy
Stored energy. Energy that an object has because of its location or structure.
Chemical potential energy
a type of potential energy stored in the chemical bonds between atoms and molecules.
Thermodynamics
The study of energy. Transformation that occur in a collection of matter.
1st Law of Thermodynamics
Energy cannot be created or destroyed. The total amount of energy in the universe is constant. However, energy can change form from one form to another.
2nd law of thermodynamics
Energy transformations increase disorder (entropy), mostly as heat (which organisms use anyway).
Entropy
A measure of randomness or disorder in a system.
Heat
A form of energy that is transferred from between objects due to a temperature difference
Anabolism
Reactions that require energy input: products contain more energy than reactants.
Catabolism
Reactions that release energy; reactions contain more energy than products.
Principle of the conservation of energy
Total energy is conserved. Energy cannot be breathed or destroyed. Energy can be converted from one form to another.
ATP
Adenosine triphosphate is a nucleotide that temporarily stores energy to transfer it around the cell. All cells rely on the potential energy transferred by ATP to power chemical reactions.
ADP
If a cell needs to spend energy to accomplish a task, the ATP molecule splits off one of its three phosphates, becoming ADP (Adenosine di-phosphate) + phosphate. The energy holding that phosphate molecule is now released and available to do work for the cell.
Metabolism
All chemical reactions in an organism.
Exergonic
Energy releasing
Endergonic
Energy consuming
Metabolic pathway
A series of metabolic reactions
Enzyme
a substance produced by a living organism which acts as a catalyst to bring about a specific biochemical reaction.
Free energy
(G) portion of a system’s energy that can do work
Spontaneous
Releases free energy. Occurs without input of matter or electrical energy into a system.
Activation energy
the energy required for a reaction to occur, and determines its rate
Active site of enzyme
the region of an enzyme where substrate molecules bind and undergo a chemical reaction.
Competitive inhibition
interruption of a chemical pathway owing to one chemical substance inhibiting the effect of another by competing with it for binding or bonding
Non competitive inhibition
a type of enzyme inhibition where the inhibitor reduces the activity of the enzyme and binds equally well to the enzyme whether or not it has already bound the substrate
Allosteric reaction
allosteric regulation is the regulation of an enzyme by binding an effector molecule at a site other than the enzyme’s active site.
Coopertivity
a phenomenon displayed by enzymes or receptors that have multiple binding sites where the affinity of the binding sites for a ligand is increased, positive cooperativity, or decreased, negative cooperativity, upon the binding of a ligand to a binding site.
