Unit 2 lecture 2 9/21/22 Flashcards
The totality of an organism’s chemical reactions is called ______
Metabolism
A _________ for a particular molecule/compound describes the series of steps involved in that transition
Metabolic path
Metabolic pathways can be classified into 2 categories:
1._____
2._____
1.Catabolic pathways
2.Anabolic pathways
______ pathways break compounds down, generally releasing energy
Catabolic
_______ pathways typically consume energy to build larger compounds
Anabolic
We will define ______ as the capacity to cause change
Energy
The study of how energy transformation occurs in relation to matter is called _______
Thermodynamics
The First law states that the amount of energy in the universe is constant, and so ____________
cannot be created or destroyed
The 2nd law states that every transfer or transformation of energy increases the ________ of the universe
entropy
________ is a measure of molecular disorder
entropy
______ is defined as the amount of energy available to perform work in systems, measured through the gibs equation: ΔG = Gfinal state - Ginitial state
Free energy
Some reactions occur ________, meaning the are energetically favorable and so will occur with no energy input
Spontaneously
Reactions which proceed with a net release of free energy are referred to as ________
exergonic reactions
______ are those which absorb free energy from the surrounding system
Endergonic
_______ is the pushing of endergonic reactions that would not occur spontaneously, Ex: polymer synthesis
Chemical work
_______ involves the pumping of substances across membranes against the direction of spontaneous movement, Ex: Sodium-potassium pumps
Transport work
________ involves the physical movement of the organism and cellular components, Ex: transport proteins
Mechanical work
Cells manage energy resources through _______, where an exergonic process is used to drive and endergonic one
Energy coupling
______ is the molecule primarily responsible for mediating the couplings
ATP
Adenosine triphosphate (ATP) contains the 5-carbon sugar Ribose, and the nitrogenous base _____
adenine
ATP, most importantly, it has a chain of ______ attached to the sugar
phosphate groups
ATP is basically a ______, except that it has 2 extra phosphate groups
Nucleotide
Energy is released from hydrolysis of the terminal phosphate group, turning ATP to ________ spontaneously
ADP (adenosine diphosphate)
It is the coupling of the phosphate group to another molecule, a process known as ______ that results in the formation of a phosphorylated intermediate
phosphorylation
_______ are chemical agents that speed up chemical reactions, without being consumed themselves
Catalysts
______ are biological catalysts, and are generally proteins and work to lower the activation energy of chemical reactions and they themselves do not change shape
Enzymes
______ is the initial investment of energy required to contort the reactant molecules so the bonds can break
Activation energy
Reactants whose reactions are accelerated by enzymatic catalysis are referred to as __________
substrates
Enzymes bind to substrates, forming the __________, From this complex, the products are formed and released, allowing the enzyme to bind more substrate
enzyme substrate complex
The specific portion of an enzyme to which substrates bind is called the ______
active site
________ bring more reactive portions of molecules into alignment by stressing the substrate molecules to facilitate a change in bonds
Enzymes
Enzymes generally target the _____ and ______
1.Hydrogen
2.Ionic bonds
Many enzymes are dependent on other, non-protein compounds to properly function called _______ these may be loosely or tightly associated with the enzyme and help facilitate processes
Cofactors
Organic cofactors are referred to as ______
coenzymes
________ block the active site of an enzyme such that it cannot bind the substrate
Competitive inhibitors
________ bind to another part of the enzyme, causing a change in shape
Noncompetitive inhibitors
Enzymes must be controlled in their catalytic activities
This may be achieved by changing ______ such that they are not produced
gene expression
Enzymes can also be ______ by controlling the activity of already present enzymes
regulated
_______ is any case in which a protein’s function at one site is affected by the binding of a regulatory molecule to a separate site which may result in either inhibition or stimulation
Allosteric regulation
_______ loop is a metabolic pathway which is halted by the inhibitory binding of its end product to an enzyme that acts early in the pathway
Feedback inhibition
