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The _______ Law of Thermodynamics states that every energy transfer or transformation increases the entropy of the universe. Chemical reactions with a NEGATIVE free energy (- Δ G) are ____________ endergonic exergonic SECOND exergonic
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AP BIOLOGYChapter 8
Metabolism
The _____ Law of Thermodynamicsstates that energy can be transformedand transferred by NEVER created or destroyed
Anabolic pathways consume energy to build molecules
release energy by breaking down molecules
The measure of disorder or randomness(symbolized by S)
FIRST
→
entropy
The _______ Law of Thermodynamicsstates that every energy transfer or transformation increases the entropy of the universe.
Chemical reactions with a NEGATIVEfree energy (- Δ G) are ____________
endergonic exergonic
SECOND
exergonic
Chemical reactions with a POSITIVEfree energy (+ Δ G) are ____________
endergonic exergonic
Most enzymes belong to which groupof macromolecules?
Molecules that speed up chemical reactions are called ____________
endergonic
proteins
catalysts
Energy associated with moving objects is called _______ energy
Catabolic pathways consume energy to build molecules
release energy by breaking down molecules
Chemical energy is a form of ___________ energy kinetic potential
kinetic
→
potential
Reactions that release free energyare called ______________
exergonic endergonic
The hydrolysis of ATP is a ________ ΔG reaction.
Catalytic proteins that speed up chemical reactions in living things are called
____________
exergonic
negative
enzymes
Reactions that absorb free energyare called ______________
exergonic endergonic
Chemical reactions with a NEGATIVEfree energy (- Δ G) are ____________
spontaneous nonspontaneous
Region on an enzyme where regulatory molecules can bind = ______________
endergonic
spontaneous
Allosteric site
Chemical reactions with a POSITIVEfree energy (+ Δ G) are ____________
spontaneous nonspontaneous
The initial investment of energy for starting a chemical reaction is called
the _______________
The place on an enzyme where the substrate attaches = _____________
nonspontaneous
Activation energy OREnergy of activation
active site
Chemical reactions with a NEGATIVEfree energy (- Δ G) are ____________
spontaneous nonspontaneous
Which kinds of bonds hold the substrate to the active site of an enzyme?
Nonprotein “helpers” for catalytic activty are called ______________
spontaneous
Weak interactions like hydrogen & ionic bonds
cofactors
If a cofactor is an organic molecule it is called a ____________
Which kind of food molecules oftenact as coenzymes?
A molecule that mimics a substrate, binds to the active site, and reduces the activity of an enzyme is called a(n) _______________ inhibitor.
coenzyme
vitamins
COMPETITIVE
______________ inhibitors slow down enzymatic reactions by binding to a site other than the active site and causing a change in the enzyme’s shape
In ___________ inhibition, a metabolic pathway is switched off by the binding of its end product.
The change in the shape of the active site of an enzyme after the substrate attaches so that it binds more snugly
is called _____________
NONCOMPETITIVE
FEEDBACK
INDUCED FIT
When the binding of one substrate molecule primes an enzyme to accept additional substrate molecules more readily it is called ______________
COOPERATIVITY
The arrow in the diagram is showing the _________________ of this reaction.ACTIVATION ENERGY
The arrow in the diagram is showing the ______________________ of this reaction.CHANGE IN FREE ENERGY (ΔG)
This reaction has a ___ Δ G because the energy of the products is greater then the reactants
+
This reaction has a ___ Δ G because the energy of the products is less then the reactants
-
How would adding an enzyme change the graph of this reaction?
Enzymes lower the activation energy of chemical reactions but don’t change theenergy of the products
Cells manage their energy resources by using the energy from exergonic (-ΔG) reactions to drive endergonic (+ΔG) reactions in a process called
____________________
ADP + Pi → ATP
This is a __ ΔG reaction.Energy coupling
+
Cellular respiration uses glucose, which has a high level of free energy and releases CO2 and H2O which have low levels of free energy.
Is respiration spontaneous or not?
Is it exergonic or endergonic?spontaneous
exergonic
How does the 2nd LAW of thermodynamics help explain the diffusion of a substance across a membrane?
The 2nd Law is the tendency toward randomness. Having equal concentrations on both sides of a membrane is more random than unequal concentrations. Diffusion from high concentration to low INCREASES THE ENTROPY as mandated by the 2nd law
If living things take simpler substances and build them into complicated systems (increase entropy), why does this NOT VIOLATE the 2nd LAW of thermodynamics ?
Living things are OPEN systems and must constantly take in energy and materials
from outside to maintain the increase in entropy