warm-up: the first law of thermodynamics states that matter and energy cannot be created or...
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Warm-UP:The first law of thermodynamics states that matter and energy cannot be created or destroyed. In the picture, identify where the matter and energy went? (Note, the scale is lying…)
Homework:DUE Thursday: Concept 8.1 10 Key IdeasDUE Friday: Free Energy POGIL
Unit 3: Enzymes
Big Idea: Reactions are either spontaneous or require energy. Enzymes are a type of protein that controls metabolism (reactions in living organisms) by creating an enzyme substrate complex. Protein function is due to protein structure. The pH of the environment influences protein structure and in turn, protein function.
Reactions are either spontaneous or require energy.
1st Law of Thermodynamics: Conservation of Matter and Energy
• The matter and energy of the Universe is constant:
• Energy can be transferred, but it cannot be created or destroyed
Reactions are either spontaneous or require energy.
1st Law of Thermodynamics: Conservation of Matter and Energy
• The matter and energy of the Universe is constant:
• Energy can be transferred, but it cannot be created or destroyed
2nd Law of Thermodynamics:
during spontaneous reactions, both enthalpy and entropy increase
• Enthalpy (∆H): energy that leaves the system as heat (exothermic)
• Entropy (∆S): matter tends towards disorder
Reactions are either spontaneous or require energy.
2nd Law of Thermodynamics:
during spontaneous reactions, both enthalpy and entropy increase
• Enthalpy (∆H): energy that leaves the system as heat (exothermic)
• Entropy (∆S): matter tends towards disorder
Reactions are either spontaneous or require energy.
Fig. 8-3
(a) First law of thermodynamics (b) Second law of thermodynamics
Chemicalenergy
Heat CO2
H2O
+
Reactions are either spontaneous or require energy.
Warm-UP:The 2nd law of thermodynamics says that enthalpy (- temperature) will decrease (backwards math) and entropy (chaos) will increase! How does the picture show this?
Homework:DUE Tomorrow: Free Energy POGIL
Reactions are either spontaneous or require energy.Metabolic Pathways:• “Change” the form of energy:
potential, heat, kinetic, chemical• rearrange atoms in a series of steps
from reactants to products• rely on ATP mediated energy coupling:
the use of an exergonic metabolic pathway to drive an endergonic one
Reactions are either spontaneous or require energy.Metabolic Pathways:• “Change” the form of energy:
potential, heat, kinetic, chemical• rearrange atoms in a series of steps
from reactants to products• rely on ATP mediated energy coupling:
the use of an exergonic metabolic pathway to drive an endergonic one
Reactions are either spontaneous or require energy.Metabolic Pathways:• “Change” the form of energy:
potential, heat, kinetic, chemical• rearrange atoms in a series of steps
from reactants to products• rely on ATP mediated energy coupling:
the use of an exergonic metabolic pathway to drive an endergonic one
Reactions are either spontaneous or require energy.Metabolic Pathways:• “Change” the form of energy:
potential, heat, kinetic, chemical• rearrange atoms in a series of steps
from reactants to products• rely on ATP mediated energy coupling:
the use of an exergonic metabolic pathway to drive an endergonic one
Warm-UP:Can you use the legos to model Catabolism? Anabolism? Draw what you did. Can you show how the products of one reaction can be the reactants for a new reaction?
DUE Now: Free Energy POGIL
Homework:DUE Monday: Concept 8.2 and 8.3 10 Key Ideas
Reactions are either spontaneous or require energy.Metabolic Pathways:• “Change” the form of energy:
potential, heat, kinetic, chemical• rearrange atoms in a series of steps
from reactants to products• rely on ATP mediated energy coupling:
the use of an exergonic metabolic pathway to drive an endergonic one
https://www.khanacademy.org/test-prep/mcat/biomolecules/overview-metabolism/v/overview-of-metabolism-anabolism-and-catabolism
Reactions are either spontaneous or require energy.Metabolic Pathways:• Anabolic Reactions:
– “add” energy (endergonic) by putting e-’s farther from highly electronegative atoms
– decrease temperature (endothermic)– increase order (decrease entropy) by
building bigger molecules• Catabolic Reactions:
– “release” energy (exergonic) by transferring energy out of the system
– increase temperature (exothermic)– increase entropy by breaking down
bigger molecules into smaller ones
Reactions are either spontaneous or require energy.Metabolic Pathways:• Anabolic Reactions:
– “add” energy (endergonic) by putting e-’s farther from highly electronegative atoms
– decrease temperature (endothermic)– increase order (decrease entropy) by
building bigger molecules• Catabolic Reactions:
– “release” energy (exergonic) by transferring energy out of the system
– increase temperature (exothermic)– increase entropy by breaking down
bigger molecules into smaller ones
Reactions are either spontaneous or require energy.Metabolic Pathways:• Anabolic Reactions:
– “add” energy (endergonic) by putting e-’s farther from highly electronegative atoms
– decrease temperature (endothermic)– increase order (decrease entropy) by
building bigger molecules• Catabolic Reactions:
– “release” energy (exergonic) by transferring energy out of the system
– increase temperature (exothermic)– increase entropy by breaking down
bigger molecules into smaller ones
https://www.khanacademy.org/test-prep/mcat/biomolecules/overview-metabolism/v/atp-hydrolysis-gibbs-free-energy
Gibbs Free Energy: • calculates the likelihood for a
reaction to occur (ie spontaneous)• dependent on enthalpy and
entropy• ∆G= ∆H -T∆S• spontaneous when energy is
released:– exergonic: ∆G < 0
• not spontaneous when energy is “stored”:– endergonic: ∆G > 0
Reactions are either spontaneous or require energy.
Reactions are either spontaneous or require energy.
Gibbs Free Energy: • calculates the likelihood for a
reaction to occur (ie spontaneous)• dependent on enthalpy and
entropy• ∆G= ∆H -T∆S• spontaneous when energy is
released:– exergonic: ∆G < 0
• not spontaneous when energy is “stored”:– endergonic: ∆G > 0
Warm-UP: Welcome to Monday! All weekend, you ate all kinds of healthy, good for you (like proteins). What do you think your body is doing with them now? “You are what you eat” means something much more than “if you eat healthy, you will be healthy.”
Homework: Worksheet for Chapter 5: Building Biomolecules
I NEED ALL TESTS RETURNED: scantron, written, and multiple choice questions. IF you did the make-up, please mark the top.
Each pair: Build an amino acid: see p. 79
Make a dipeptide
Make a polypeptide: join some other teams
Building Proteins
Building Proteins
Analysis:1. A polypeptide was 8 amino acids long. How many
waters were produced when it was polymerized?2. What could make one protein different than
another?3. How are the proteins we eat made into the proteins
we’re made of?4. Proteins are not just linear chains of amino acids.
Predict how they form many different shapes.
Building Proteins
Analysis:1. A polypeptide was 8 amino acids long. How many waters
were produced when it was polymerized? 72. What could make one protein different than another? Order
of amino acids, type of amino acids, bonds made between amino acids, length of polypeptide
3. How are the proteins we eat made into the proteins we’re made of? Polypeptides are disassembled (catabolism) into amino acids, then reassembled (anabolism) into the correct order for our proteins (by reading our genes)
4. Proteins are not just linear chains of amino acids. Predict how they form many different shapes. Interactions between R groups
Protein function is due to protein structure.
Amino Acid (subunit: monomer)• organic molecules with amino group and
carboxylic acid (carboxyl group)• differ in their properties due to differing side
chains (R groups)• linked by peptide bonds
Polypeptides • polymers built from the same set of 20 amino
acids• range in length from a few to more than a
thousand amino acids• Each has a unique linear sequence of amino
acids
Protein • consists of one or more polypeptides
Protein function is due to protein structure.
Protein function is due to protein structure.Amino Acid (subunit: monomer)• organic molecules with amino group and
carboxylic acid (carboxyl group)• differ in their properties due to differing side
chains (R groups)• linked by peptide bonds
Polypeptides • polymers built from the same set of 20 amino
acids• range in length from a few to more than a
thousand amino acids• Each has a unique linear sequence of amino
acids
Protein • consists of one or more polypeptides
Amino Acid (subunit: monomer)• organic molecules with amino group and
carboxylic acid (carboxyl group)• differ in their properties due to differing
side chains (R groups)• linked by peptide bonds
Polypeptides • polymers built from the same set of 20
amino acids• range in length from a few to more than a
thousand amino acids• Each has a unique linear sequence of
amino acids
Protein • consists of one or more polypeptides
Protein function is due to protein structure.
Protein function is due to protein structure.
4 Levels of Protein Structure:
PRIMARY: sequence of amino acids
SECONDARY: hydrogen bonds between amino and carboxyl groups
TERTIARY: interactions between R groups
QUATERNARY: proteins are usually made of multiple polypeptide chains
Protein function is due to protein structure.
Fig. 5-21f
Polypeptidebackbone
Hydrophobicinteractions
Disulfide bridge
Ionic bond
Hydrogenbond
Fig. 5-21
PrimaryStructure
SecondaryStructure
TertiaryStructure
pleated sheet
Examples ofamino acidsubunits
+H3N Amino end
helix
QuaternaryStructure
Protein function is due to protein structure.Conformation:• “shape”• due to interactions between R
groups: tertiary structure• because it gives the protein its
structure, it therefore gives the protein its function
• can be denatured (changed shape) when R group interactions are changed (due to changes in environment)
Protein function is due to protein structure.Conformation:• “shape”• due to interactions between R
groups: tertiary structure• because it gives the protein its
structure, it therefore gives the protein its function
• can be denatured (changed shape) when R group interactions are changed (due to changes in environment)
Protein function is due to protein structure.Conformation:• “shape”• due to interactions between R
groups: tertiary structure• because it gives the protein its
structure, it therefore gives the protein its function
• can be denatured (changed shape) when R group interactions are changed (due to changes in environment)
Check out a computer for you and a partner
No Warm-UP
Go to my website. See documents tab: “Modeling Protein Structure”. Follow directions.
When finished, submit to turnitin.com. DUE by Friday 11/6
Please have out your homework: Building Biomolecules
Warm-UP: What happened to the protein paravalbumin when cooked? In other words, what happens to an egg when you cook it? When you refrigerate it, does it turn back?
Due Friday: Modeling Protein Structure
Due Friday: Sickle Cell Poster
Protein function is due to protein structure.Conformation:• “shape”• due to interactions between R
groups: tertiary structure• because it gives the protein its
structure, it therefore gives the protein its function
• can be denatured (changed shape) when R group interactions are changed (due to changes in environment)
Protein function is due to protein structure.Conformation:• “shape”• due to interactions between R
groups: tertiary structure• because it gives the protein its
structure, it therefore gives the protein its function
• can be denatured (changed shape) when R group interactions are changed (due to changes in environment)
Protein function is due to protein structure.Conformation:• “shape”• due to interactions between R
groups: tertiary structure• because it gives the protein its
structure, it therefore gives the protein its function
• can be denatured (changed shape) when R group interactions are changed (due to changes in environment)
• heat• pH• genetics (change in gene results
in change in primary structure)
Sickle Cell Disease Poster
Your poster needs to include the following:
1. Compare the PRIMARY structure of Hemoglobin A and Hemoglobin S using drawings and explanations• Molecular drawings of amino acids: 5th, 6th, 7th See
p. 79 and p.84• Dehydration reaction: Show the amino acids
forming into a polypeptide2. Compare the TERTIARY structure of Hemoglobin A and
Hemoglobin S using drawings and explanations• Describe R group interactions that are different in
each version of the polypeptide3. Explain the cellular and organismal level changes that
result.
Sickle Cell Disease Poster
Terms:central carbonR grouphydrophobichydrophilicpolarnon polarprimary structuretertiary structurequaternary structurered blood cell
hemoglobin Ahemoglobin Samine groupcarboxyl groupwaterdehydrationamino acidpolypeptideoxygen
Sickle Cell Disease Poster
4 Advanced 3 Proficient 2 Basic 1 Below Basic
Scientific Vocabulary
ALL words are used correctly
Most words are used correctly
Most words are used, some correctly
Some words are used correctly
Labeled Molecular Drawings
Drawings are detailed and help explain
Drawings help explain some things
Drawings are complete but lack detail
Drawings are incomplete
Explanations of changes from primary, to tertiary, to organism
Poster clearly explains the details of how primary structure changes can lead to organismal changes
Poster explains changes, but lacks details about the process
Poster shows changes but lacks complete explanation of how the small changes have organismal effects
Project has very little information about changes.
Warm-UP: Compare the 2 models. How does each help you understand proteins? Is there value in each?
Due Friday: Modeling Protein Structure
Due Friday: Sickle Cell Poster
Warm-UP: Enzymes are a type of protein that speed up reactions. How do you think they do this? Use the model to explain.
Due Wednesday: 10 Key Ideas Concept 8.4
Due: Sickle Cell Poster AND Modeling Protein Structure
Due Thursday: Enzyme-Substrate Model (Wed.’s Activity finished)
Enzymes are a type of protein that controls metabolism (reactions in living organisms) by creating an enzyme substrate complex.
enzymes: usually end in “ase”• a type of protein• the enzyme substrate complex: the enzyme’s
conformation “matches” a substrate: substrate specific
• are catalysts: speed up the rate of reactions• induced fit: lower activation energy (making them
“more” spontaneous) by “straining” substrate bonds
• are unchanged by reactions
substrate: • the molecule acted on• AKA the reactants• are changed into products• fit in the “active site”
example: sucrasesucrose → glucose + fructose
Enzymes are a type of protein that controls metabolism (reactions in living organisms) by creating an enzyme substrate complex.
enzymes: usually end in “ase”• a type of protein• the enzyme substrate complex: the enzyme’s
conformation “matches” a substrate: substrate specific
• are catalysts: speed up the rate of reactions• induced fit: lower activation energy (making them
“more” spontaneous) by “straining” substrate bonds
• are unchanged by reactions
substrate: • the molecule acted on• AKA the reactants• are changed into products• fit in the “active site”
example: sucrasesucrose → glucose + fructose
Enzymes are a type of protein that controls metabolism (reactions in living organisms) by creating an enzyme substrate complex.
enzymes: usually end in “ase”• a type of protein• the enzyme substrate complex: the enzyme’s
conformation “matches” a substrate: substrate specific
• are catalysts: speed up the rate of reactions• induced fit: lower activation energy (making them
“more” spontaneous) by “straining” substrate bonds
• are unchanged by reactions
substrate: • the molecule acted on• AKA the reactants• are changed into products• fit in the “active site”
example: sucrasesucrose → glucose + fructose
Enzymes are a type of protein that controls metabolism (reactions in living organisms) by creating an enzyme substrate complex.
enzymes: usually end in “ase”• a type of protein• the enzyme substrate complex: the enzyme’s
conformation “matches” a substrate: substrate specific
• are catalysts: speed up the rate of reactions• induced fit: lower activation energy (making them
“more” spontaneous) by “straining” substrate bonds
• are unchanged by reactions
substrate: • the molecule acted on• AKA the reactants• are changed into products• fit in the “active site”
example: sucrasesucrose → glucose + fructose
Enzymes are a type of protein that controls metabolism (reactions in living organisms) by creating an enzyme substrate complex.
enzymes: usually end in “ase”• a type of protein• the enzyme substrate complex: the enzyme’s
conformation “matches” a substrate: substrate specific
• are catalysts: speed up the rate of reactions• induced fit: lower activation energy (making them
“more” spontaneous) by “straining” substrate bonds
• are unchanged by reactions
substrate: • the molecule acted on• AKA the reactants• are changed into products• fit in the “active site”
example: sucrasesucrose → glucose + fructose
Enzymes are a type of protein that controls metabolism (reactions in living organisms) by creating an enzyme substrate complex.
enzymes: usually end in “ase”• a type of protein• the enzyme substrate complex: the enzyme’s
conformation “matches” a substrate: substrate specific
• are catalysts: speed up the rate of reactions• induced fit: lower activation energy (making them
“more” spontaneous) by “straining” substrate bonds
• are unchanged by reactions
substrate: • the molecule acted on• AKA the reactants• are changed into products• fit in the “active site”
example: sucrasesucrose → glucose + fructose
Homework DUE tomorrow: Experimental Design: Question, Alternative Hypothesis, Procedure (sketch is enough)
Warm-UP1. Describe the graph. How do the two rates compare?2. Explain the graph. What happened to the penny flipase in the two situations?
stamp today, then turn in Warm-UP sheet: Key Ideas 8.4
DUE: Penny Modeling Lab; in my basket
Lab: Factors that Effect Enzyme Rate
Question: How will ______________ affect the rate of an enzymatic reaction?
Hypothesis with reason:
Lab: Factors that Effect Enzyme Rate
YOUR EXPERIMENTAL DESIGN1. Investigative Question2. Alternative Hypothesis:
– What do you know about enzymes that makes you think so?
3. Procedure: sketch is enough
Materials:
Erlenmeyer flaskH2O2
peroxidase (orange tube)
H2O in a 100 mL beaker
plastic pippetepipettepipette tips
computerinterface + 2 cables (USB and power)pressure sensorpocket computer
Procedure: Determining a Baseline1. Using a clean 10 mL pipette, add to an Erlenmeyer
flask: – 5 mL of 3.0% H2O2 – 5 mL of water
2. Add 5 drops of peroxidase (enzyme suspension) to Erlenmeyer flask
3. QUICKLY place the pressure sensor on the Erlenmeyer flask. Click COLLECT to begin data collection.
4. When rubber stopper “pops” off, click STOP. Data collection has finished.
5. Move your data to EXCEL. Save your EXCEL file.6. Rinse the flask with water.7. Repeat AT LEAST 5 trials.
Homework DUE Monday: Experimental Design Draft 2
Warm-UP: Read your question and hypothesis to your teammates. Who has the best plan for an investigation?
Stamp Today: Experimental Design Draft 1
YOUR EXPERIMENTAL DESIGN (decide on one)1. Investigative Question2. Alternative Hypothesis:
– What do you know about enzymes that makes you think so?
3. Procedure: sketch is enough
Whiteboard:
Lab: Factors that Effect Enzyme Rate
Gallery Walk• Clarifying Questions:
– Do you understand their set-up?– Do you understand their question?
• Probing Questions: Press your classmates1. Do they have a valid experiment? Does their set-up
answer their investigative question?2. Will their experiment be reliable? controls?3. Enzymes? Does the experiment help us understand
factors that influence enzymes?
Homework DUE Tuesday: 10 Key Ideas: Concept 3.3. STOP when you get to “Buffers”
Warm-UP: 1. Read your ALTERNATIVE HYPOTHESIS to your
teammates. Who do you agree with? Why?2. To reject your null, you’ll need stats. To do stats,
you need TWO sets of numbers to compare. What TWO sets of numbers will you compare?
Stamp Today: Experimental Design Draft 2
UNIT 3 TEST NEXT Monday-Tuesday. See my website for the study guide which is DUE next Monday for the opportunity to do the test make-up.
Warm-UP: CAN YOU CALCULATE RATE?1. Calculate the rate of the reaction from
a. 0-30 sec for 10mL of H2O2
b. 120-150 sec for 10mL of H2O2?
2. Compare the reaction rates when there is more substrate.
UNIT 3 TEST NEXT Monday-Tuesday. See my website for the study guide which is DUE next Monday for the opportunity to do the test make-up.
Homework DUE Thursday: Enzyme Substrate Graph Comparisons
Stamp Today: Changes Due to Acids and Bases
Procedure: Calculating Statistics1. Create a line graph for Condition 1, with all 4 trials.
i. Organize data with time in Column A, Trial 1 in Column B, Trial 2 in Column C, Trial 3 in Column D, Trial 4 in Column E
ii. Drag a box around Column A through Eiii. Insert a scatter plotiv. Add a trendline for each trial. Display equation on Chart.
2. Repeat with Condition 2.3. Calculate stats using slope of each line. Choose ONE of
the two options: A or BA. Open Stats Spreadsheet (see documents tab on my website).
Add slope from each trendline to the data table. The spreadsheet will calculate mean, standard deviation, and percent confidence for you.
B. Do stats by hand using slope from each trendline. Calculate mean, standard deviation, calculated t. Compare calculated t to table t to estimate percent confidence.
Draw a Bohr model of hydrogen. Label: proton, neutron, electron.
Draw a second Bohr model of hydrogen. This time it’s a hydrogen ion. Take away the electron. What’s left?
Warm-UP
UNIT 3 TEST NEXT Monday-Tuesday. See my website for the study guide which is DUE next Monday for the opportunity to do the test make-up.
Lab Report: Enzymes DUE Monday
The pH of the environment influences protein structure and in turn, protein function.
• pH: measures changes due to more or less protons• Water normally occasionally (<1%) dissociates:
• H2O H+ + OH-• [H+] = [OH-]
• Acid: • increases the H+ concentration in a solution
[H+] > [OH-]• Acid donates H+ to water
• Example: HCl H+ + Cl-• Effect on Proteins: Causes hydrogen bonds in
R groups to make hydrogen bonds with the H+ in solution
• Base: • reduces the H+ concentration in a solution [H+]
< [OH-]• free H+ bond to the base
• Example: NH3 + H+ NH4+
• Base donates OH- to water• Example: NaOH Na+ + OH-
• Effect on Proteins: Causes hydrogen bonds in R groups to make hydrogen bonds with the OH- in solution
The pH of the environment influences protein structure and in turn, protein function.
• pH: measures changes due to more or less protons• Water normally occasionally (<1%) dissociates:
• H2O H+ + OH-• [H+] = [OH-]
• Acid: • increases the H+ concentration in a solution
[H+] > [OH-]• Acid donates H+ to water
• Example: HCl H+ + Cl-• Effect on Proteins: Causes hydrogen bonds in
R groups to make hydrogen bonds with the H+ in solution
• Base: • reduces the H+ concentration in a solution [H+]
< [OH-]• free H+ bond to the base
• Example: NH3 + H+ NH4+
• Base donates OH- to water• Example: NaOH Na+ + OH-
• Effect on Proteins: Causes hydrogen bonds in R groups to make hydrogen bonds with the OH- in solution
The pH of the environment influences protein structure and in turn, protein function.
If you add vinegar (solute) to water (solvent), the H+ concentration of the solution increases while the OH- concentration stays the same. You’ve made an acidic solution.
• pH: measures changes due to more or less protons• Water normally occasionally (<1%) dissociates:
• H2O H+ + OH-• [H+] = [OH-]
• Acid: • increases the H+ concentration in a solution
[H+] > [OH-]• Acid donates H+ to water
• Example: HCl H+ + Cl-• Effect on Proteins: Causes hydrogen bonds in
R groups to make hydrogen bonds with the H+ in solution
• Base: • reduces the H+ concentration in a solution [H+]
< [OH-]• free H+ bond to the base
• Example: NH3 + H+ NH4+
• Base donates OH- to water• Example: NaOH Na+ + OH-
• Effect on Proteins: Causes hydrogen bonds in R groups to make hydrogen bonds with the OH- in solution
The pH of the environment influences protein structure and in turn, protein function.
• pH: measures changes due to more or less protons• Water normally occasionally (<1%) dissociates:
• H2O H+ + OH-• [H+] = [OH-]
• Acid: • increases the H+ concentration in a solution
[H+] > [OH-]• Acid donates H+ to water
• Example: HCl H+ + Cl-• Effect on Proteins: Causes hydrogen bonds in
R groups to make hydrogen bonds with the H+ in solution
• Base: • reduces the H+ concentration in a solution [H+]
< [OH-]• free H+ bond to the base
• Example: NH3 + H+ NH4+
• Base donates OH- to water• Example: NaOH Na+ + OH-
• Effect on Proteins: Causes hydrogen bonds in R groups to make hydrogen bonds with the OH- in solution
If you add ammonia (solute) to water (solvent), the H+ concentration of the solution decreases while the OH- concentration stays the same. You’ve made a basic solution.
The pH of the environment influences protein structure and in turn, protein function.
• pH: measures changes due to more or less protons• Water normally occasionally (<1%) dissociates:
• H2O H+ + OH-• [H+] = [OH-]
• Acid: • increases the H+ concentration in a solution
[H+] > [OH-]• Acid donates H+ to water
• Example: HCl H+ + Cl-• Effect on Proteins: Causes hydrogen bonds in
R groups to make hydrogen bonds with the H+ in solution
• Base: • reduces the H+ concentration in a solution [H+]
< [OH-]• free H+ bond to the base
• Example: NH3 + H+ NH4+
• Base donates OH- to water• Example: NaOH Na+ + OH-
• Effect on Proteins: Causes hydrogen bonds in R groups to make hydrogen bonds with the OH- in solution
The pH of the environment influences protein structure and in turn, protein function.
• pH: measures changes due to more or less protons• Water normally occasionally (<1%) dissociates:
• H2O H+ + OH-• [H+] = [OH-]
• Acid: • increases the H+ concentration in a solution
[H+] > [OH-]• Acid donates H+ to water
• Example: HCl H+ + Cl-• Effect on Proteins: Causes hydrogen bonds in
R groups to make hydrogen bonds with the H+ in solution
• Base: • reduces the H+ concentration in a solution [H+]
< [OH-]• free H+ bond to the base
• Example: NH3 + H+ NH4+
• Base donates OH- to water• Example: NaOH Na+ + OH-
• Effect on Proteins: Causes hydrogen bonds in R groups to make hydrogen bonds with the OH- in solution
The pH of the environment influences protein structure and in turn, protein function.
Denaturation:• loss of a protein’s conformation due to changes
in• pH• heat• genetics
• breaking R group interactions: tertiary structure
Why does pH matter to enzymes?• Disrupts R group interactions: changing number
of possible hydrogen bonds in the environment• Changes protein conformation (tertiary shape)• Changes function of enzyme
Optimal pH: • the pH at which the enzyme’s active site best
matches the substrate• Causes highest rate of enzyme activity (ie fastest
rate of product produced)
The pH of the environment influences protein structure and in turn, protein function.
Denaturation:• loss of a protein’s conformation due to changes
in• pH• heat• genetics
• breaking R group interactions: tertiary structure
Why does pH matter to enzymes?• Disrupts R group interactions: changing number
of possible hydrogen bonds in the environment• Changes protein conformation (tertiary shape)• Changes function of enzyme
Optimal pH: • the pH at which the enzyme’s active site best
matches the substrate• Causes highest rate of enzyme activity (ie fastest
rate of product produced)
pH• Scale is “backwards”• Neutral Solution:
• [H+] = [OH-]• pH= 7
• Acidic Solution: • [H+] > [OH-]• pH < 7
• Basic Solution: • [H+] < [OH-]• pH > 7
The pH of the environment influences protein structure and in turn, protein function.
Whiteboard:Question:
Graph
Conclusion:• Answer your question and Reject/Fail to Reject H0• Use data• Why does this make sense? What do you know about enzymes
that explains your data? OR Why are you surprised?
What is happening to the protein that’s causing it to be denatured?
Warm-UP
UNIT 3 TEST NEXT Monday-Tuesday. See my website for the study guide which is DUE next Monday for the opportunity to do the test make-up.
Lab Report: Enzymes DUE Monday
Description PointsIntroduction• Why interesting? How will this question
contribute to science? What were you curious about
1 2 3
Design:• Question• Variables• Hypotheses: null & alternative• Materials• Procedure: is your experiment repeatable
with the procedure given?
1 2 3 4 5
Data: in a table 1 2
Graph: electronic; scatter plot; labeled axes; trendline
1 2 3 4 5
Analysis• Calculations: RATE of REACTION• Sources of error
1 2 3
Conclusion• Answer: reject or fail to reject the null• Include data to support your answer• Explanation: Why does this make sense?• What alternative explanations should you
consider that might also explain your results?
1 2 3 4 5 6 7
Professionalism: ON TIME, SHOWS EFFORT, REPORT FOLLOWS A LOGICAL ORDER
1 2 3 4 5
Total 30
Lab Enzymes Name: Lab Enzymes Name:
Description PointsIntroduction• Why interesting? How will this question
contribute to science? What were you curious about
1 2 3
Design:• Question• Variables• Hypotheses: null & alternative• Materials• Procedure: is your experiment repeatable
with the procedure given?
1 2 3 4 5
Data: in a table 1 2
Graph: electronic; scatter plot; labeled axes; trendline
1 2 3 4 5
Analysis• Calculations: RATE of REACTION• Sources of error
1 2 3
Conclusion• Answer: reject or fail to reject the null• Include data to support your answer• Explanation: Why does this make sense?• What alternative explanations should you
consider that might also explain your results?
1 2 3 4 5 6 7
Professionalism: ON TIME, SHOWS EFFORT, REPORT FOLLOWS A LOGICAL ORDER
1 2 3 4 5
Total 30
Fig. 5-21g
Polypeptidechain
Chains
HemeIron
Chains
CollagenHemoglobin
Competitive inhibitors bind to the active site of an enzyme, competing with the substrate
Noncompetitive inhibitors bind to the allosteric site of an enzyme, causing the enzyme to change shape and making the active site less effective
Examples: toxins, poisons, pesticides, pharmaceutical drugs, and antibiotics
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