Thermodynamic Principles (PowerPoint) Madison 2005

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Interfacing Chemistry and Biology Since 2005
HEAT
IT
UP!
Helping Empower All To
Important Thermodynamic
Unifying Principles
Outline of teachable unit:
Day 1: Provide an environment that reduces the
fear of chemistry in students.
Day 2: Chemical equilibrium, steady state, as well
as how and why cells/life are not at equilibrium
Day 3: Chemical potential, entropy, and diffusion
Day 4: Enzyme kinetics, catalysis, transition states,
binding of substrate, and activation energy
With which of the following
are you least comfortable?
a. Physiology
b. Molecular Biology
c. Genetics
d. Thermodynamics
e. Ecology
Ratio of the Concentration of Products:Reactants
___________________________________________________________________
When you see the graph above, how do you feel about interpreting it?
aconfident
bif I have to
cneutral
dwary
escared out of my mind…I am dropping biology immediately!
Ratio of the Concentration of Products:Reactants
Based on these data which reaction would have the highest ratio of the
concentration of products:reactants at equilibrium?
A – green (bottom)
B – blue (middle)
C – red (top)
Some basic biology:
1. Why do we eat?
Some basic biology:
1. Why do we eat?
2. Where is this energy used
in our body?
Some basic biology:
1. Why do we eat?
2. Where is this energy used
in our body?
3. Why do cells need energy?
From where might the energy come
that is required for these cellular
processes we just discussed?
a.
b.
c.
d.
e.
The oxygen we breathe
The water we ingest
The caffeine we drink
The vitamin pills we take
The sugar we break down
Can energy be created?
Can energy be destroyed?
Energy Releasing Reactions
Energy Requiring Reactions
Energy Releasing Reactions
Biological processes can COUPLE these reactions
Energy Requiring Reactions
Ratio of the Concentration of Products:Reactants
Ratio of the Concentration of Products:Reactants
Figure 5.16 Making a polypeptide chain
Figure 5.16 Making a polypeptide chain
The ∆G for
this reaction
is 6 kcal/mole
In the cells of your body, glucose and
oxygen are converted to carbon dioxide
and water.
This process is called cellular respiration.
Consider the synthesis in a cell of a protein having 101
amino acid subunits. This requires the formation of 100
peptide bonds. The DG for peptide bond formation is 6 kcal/mol.
The complete breakdown of glucose in cellular respiration
releases 600 kcal/mole.
How many moles of glucose molecules does it take to make
a mole of this protein?
a. < 1
a. 1
b. > 1
∆Go’
Standard State
∆Go’
Standard State
∆Go’
Equilibrium Point
Based on the lesson just presented, when you see the graph above,
how do you feel about interpreting it?
aconfident
bif I have to
cneutral
dwary
eSTILL scared out of my mind…I am dropping biology immediately!
Based on these data which reaction(s) would have the lowest ratio of the
concentration of products:reactants at equilibrium?
A – green (bottom)
B – blue (middle)
C – red (top)
Congratulations!
You just did thermodynamics!!!
A <---> B
B <---> C
Sum of above
reactions:
Homework 1: The reactions A <---> B and B <---> C occur
sequentially and can be summed to yield the reaction A <---> C.
What is the DG of this reaction when the reaction occurs under
standard state conditions?
Homework 2: Concept map. See course web site for instructions.
A <---> C
“Much to
learn, you
still have.”
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
Cornell University
Kuei-Chiu Chen
Tom Owens
Dartmouth College
Jon Kull
Roger Sloboda
Rutgers, the State University of NJ
Diana Martin
Gregg Transue
University of Alabama
Kim Caldwell
And driven mercilessly by:
Ishrat Khan (Clark Atlanta) and Lillian Tong (University of Wisconsin-Madison)
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