Unit 3
Biochemistry
Name ______________
Period _____
1
Key Understandings
1. ______________________________________________________________________________
____________________________________________________________________
2. ______________________________________________________________________________
____________________________________________________________________
3. ______________________________________________________________________________
Unit 3 Vocabulary
1. atom smallest particle of an element
2. atomic mass total mass of the protons and neutrons in an atom, measured in atomic mass units
3. atomic number the number of protons in the nucleus of an atom
4. biomolecule a molecule that naturally occurs in living organisms, consisting primarily of carbon and
hydrogen but also nitrogen, oxygen, phosphorus and sulfur
5. carbohydrate compound made up of carbon, hydrogen, and oxygen atoms; major source of energy
for the human body
6. catalase Enzyme responsible for breaking down hydrogen peroxide into water and oxygen
7. compound a substance formed by chemical union of two or more elements or ingredients in definite
proportion by weight
8. covalent bond a chemical bond that involves sharing a pair of electrons between atoms in a molecule
9. dehydration synthesis Process in which water is removed to join two small molecules
10. electron negatively charged particle; located outside the atomic nucleus
11. element any substance that cannot be broken down into simpler substances
12. enzyme specialized proteins that speed up chemical reactions
13. hydrogen bond Weak attraction between a hydrogen atom and another atom
14. hydrolysis Breaking down complex molecules by the chemical addition of water
15. ion atom that has a positive or negative charge
16. ionic bond formed when one or more electrons are transferred from one atom to another
17. isotope one of two or more atoms with the same atomic number but with different numbers of
neutrons
18. lactase enzyme that breaks down lactose
19. lipid macromolecule made mainly from carbon and hydrogen atoms; includes fats, oils, and waxes
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20. neutron a subatomic particle that has no charge and that is found in the nucleus of an atom
21. nucleic acid An organic compound, either RNA or DNA, whose molecules are made up of one or two
chains of nucleotides and carry genetic information
22. product a chemical substance formed as a result of a chemical reaction
23. protease Enzyme that breaks down proteins
24. protein macromolecule that contains carbon, hydrogen, oxygen, and nitrogen; needed by the body
for growth and repair and to make up enzymes
25. proton a subatomic particle that has a positive charge and that is found in the nucleus of an atom
26. reactant a chemical substance that is present at the start of a chemical reaction
27. salivary amylase Enzyme
Extra Notes Page
3
Biomolecules Notes
What is a Biomolecule?


Organic molecule made by _______________________organisms
Consist mostly of _________________(C), _______________(H), and _________________ (O)
But wait…What is an Organic Molecule?


Organic Molecules:
o Contain carbon
o Considered the “_________________________”
Inorganic Molecules:
o _______________________________ contain carbon
Monomers vs. Polymers


Monomers:
o Molecules that may react with similar molecules to _____________________________
Polymers:
o A chain of many monomers that are __________________________________ together
Formation of Polymers

How are polymers formed?
o _______________________________________ (Condensation): Two hydrogen atoms
and one oxygen atom are removed from the monomers to form water, and the two
monomers are joined together.
Breakdown of Polymers

How are polymers broken down?
o _________________________—the reverse of dehydration synthesis (condensation)
o Water added to the polymer, un-linking the chain and breaking it back down to its
original monomer units
Carbohydrates


What are they?
o Group of organic molecules that includes ______________________________________
Structure:
o Carbon, hydrogen and oxygen in a 1:2:1 ratio
o (CH2O)n – n is an integer such as 5 (C5H10O5)
o Subunits:_______________________________________, such as glucose or fructose
o Most often in a _______________________________________
o Subunits are connected with covalent bonds
Draw a monosaccharide
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
Function:
o _________________________________
o Structural _______________________________
o Cell __________________________
o Cell Membrane Marker
Lipids


What are they?
o Organic molecule group including ____________________________________________
Structure:
o Subunits:
 ____________________________________________________
 Glycerol and fatty acids plus phosphate group
o _____________________________________ in water
o Do not form large polymers (2 or 3 fatty acids with glycerol)
 Examples: diglyceride and triglyceride
Draw a Triglyceride
Draw a Phospholipid

Function:
o ______________________________
o Insulation
o Part of _________________________________________ (phospholipids)
o Hormones
Proteins


What are proteins?
o Group of organic molecules that provides structure and facilitates __________________
Structure:
o Subunits:__________________________________________
o Amino acids connect via peptide bonds
o Very _____________________ molecules
o Globular or structural
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Draw an Amino Acid

Function:
o Lots of functions!
o __________________________ (speed rate of chemical reactions)
o Structural components in cells
o Mechanical functions in muscles and cytoskeleton (internal cell framework)
o Cell signaling
o __________________________________ response
Nucleic Acids


What are Nucleic Acids?
o Group of organic molecules including ____________________________________
Structure:
o Subunits are _________________________—5-Carbon sugar, Nitrogen base and one or
more Phosphate groups
Draw a Nucleotide

Function:
o Storage and retrieval of information:
o Encode _______________________________
o Gene _________________________________
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MACROMOLECULE FOLDABLE
Fold and cut a piece of paper as shown below to make 4 tabs.
FRONT SIDE OF
TABS:
Tab A
1. Label the tab PROTEIN
2. Sketch and color an AMINO ACID
3. Name the monomer
4. Name the polymer
TAB B
1. Label the tab CARBOHYDRATE
2. Sketch and color a molecule of GLUCOSE
3. Name the monomer
4. Name the polymer
TAB C
1. Label the tab LIPID
2. Sketch and label a TRIGLYCERIDE
3. Name the monomer
4. Name the polymer
TAB D
1. Label the tab NUCLEIC ACID
2. Sketch and color a NUCLEOTIDE
3. Name the monomer
4. Name the polymer
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BACK SIDE OF TABS;
TAB A
1. Give 4 FUNCTIONS OF PROTEINS
2. List 2 EXAMPLES OF PROTEINS
TAB B
1. Give 2 FUNCTIONS OF CARBOHYDRATES
2. List 4 EXAMPLES OF CARBOHYDRATES
TAB C
1. Give 2 FUNCTIONS OF LIPIDS
2. List 4 EXAMPLES OF LIPIDS
TAB D
1. Give 2 FUNCTIONS FOR NUCLEIC ACIDS
2. List 2 EXAMPLES OF NUCLEIC ACIDS
ON THE INSIDE CENTER SECTION, center and write the word MACROMOLECULE
1. Write the terms CONDENSATION and HYDROLYSIS and define them.
2. Draw the condensation reaction for joining 2 amino acids to form a dipeptide.
ON THE BACK OF THE FOLDABLE, write your NAME and PERIOD.
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McMush Lab
Introduction:
Carbohydrates, proteins, fats, vitamins, and other nutrients provide your body with energy necessary
to carry on life activities. These compounds are present in the plants and animals you use as food. In this
lab, you will test for specific compounds and then determine if those compounds are present in ordinary
foods.
Objective:
To determine the compounds present in food.
Procedure: Part I - Testing of Known Substances
Protein test:
1. Place 5 ml of the gelatin solution into your test tube.
2. Add ten drops of Biuret solution.
3. Observe any color change
Glucose test:
1.
2.
3.
4.
5.
Place 5 ml of the glucose solution into your test tube.
Add 3 ml of Benedict's solution.
Place the tube in a beaker of boiling water and boil for five minutes
Use test tube clamps to hold hot test tubes.
Observe any color change
Starch test:
1. Place 5 ml of the starch solution into your test tube.
2. Add 5 drops of Lugol's iodine solution.
3. Observe any color change
Vitamin C test:
1. Place 5 ml of the lipid solution into your test tube.
2. Add 5 drops of Sudan III
3. Observe any color change
Record your results in a data table:
Food Substance
Sugar
Glucose
Starch
Lipids
Reagent test
Biuret solution
Benedict's solution
Lugol's iodine solution
Sudan III solution
Results
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Procedure: Part II - Testing McMush
1. Predict the substances you will find in the McMush solution. Record your predictions in the data
table using a “ +” or “-“.
2. Perform the reagent tests, just like in procedure part 1,but using 5 ml of the McMush solution.
3. Describe and record your results.
Food Substance
Protein
Sugar
Starch
Lipid
Prediction
Reagent test
Biuret Solution
Benedict's Solution
Lugol's Solution
Sudan III Solution
Results
Analysis:
1. How are monomers and polymers different?
2. What are the monomers for each of these macromolecules?
a. Carbohydrate –
b. Lipids –
c. Proteins –
3. Circle ANY of the following compounds that would be classified as a carbohydrate.
a. Amino acid
e. fructose
b. Triglyceride
f. hemoglobin
c. Glucose
g. chitin
d. Enzymes
h. starch
4. If you were given an unknown food sample and asked to identify its contents, which test would
you use to determine the presence of:
a. Lipids –
b. Proteins –
c. Glucose –
d. Starch –
5. Predict which macromolecule should be present in the following food substances and indicate
which test you would apply in order to detect the presence of that macromolecule. You may
need to consult additional resources.
Food Substance
Potato juice
Cracker
Egg white
Honey
Predicted Macromolecule
Test to be Used
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Enzyme Notes
What Are Enzymes?



Most enzymes are _______________________(tertiary and quaternary structures)
Act as Catalyst to __________________________________a reaction
_______________________________________________________ in the process
Enzymes



Are _____________________________ for what they will catalyze
Are _______________________________
End in _________________________
o -Sucrase
o -Lactase
o -Maltase
How do enzymes Work?

Enzymes work by weakening ________________ which _______________ activation energy
Draw the graph showing a reaction rate with and without enzymes.
Enzyme-Substrate Complex

The substance (reactant) an enzyme acts on is the __________________________
Active Site

A restricted region of an enzyme molecule which _____________________ to the substrate.
Label the Enzyme-Substrate Complex
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Induced Fit




A change in the___________________ of an enzyme’s ________________________________
Induced by the _____________________________
A change in the ________________ of an enzyme’s active site (H+ and ionic bonds are involved).
Induced by the substrate.
What Affects Enzyme Activity?

Three factors:
o ________________________________ Conditions
o _____________________________ and Coenzymes
o Enzyme _____________________________
Environmental Conditions



Extreme ______________________________ are the most dangerous
o high temps may denature (unfold) the enzyme.
______________(most like 6 - 8 pH near neutral)
________________________ concentration (salt ions)
Cofactors and Coenzymes


_________________________ substances (zinc, iron) and vitamins (respectively) are sometimes
needed for proper enzymatic activity.
Example:
o __________ must be present in the quaternary structure - hemoglobin in order for it to
pick up __________________________
Two examples of Enzyme Inhibitors




Competitive inhibitors:
o are chemicals that resemble an enzyme’s normal substrate
and________________________ with it for the active site.
Draw a Competitive Inhibitor
Noncompetitive inhibitors:
o Inhibitors that __________________enter the active site, but bind to another part of
the enzyme causing the enzyme to change its _______________, which in turn alters
the active site.
Draw a Noncompetitive Inhibitor
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Released EOC Questions
1. Enzymes are proteins that help increase the rate of chemical reactions inside cells. These
proteins are composed of many simpler molecules called amino acids. Which of the following
suggests that the shape of an enzyme determines the enzyme’s function?
a.
b.
c.
d.
Enzymes are specific to a substrate
Enzymes can operate in a wide range of conditions
Enzymes are activated by neighboring molecules
Enzymes can be found in all life-forms
2. Proteins and polysaccharides are polymers. These polymers are formed by dehydration
synthesis. Which statement correctly identifies a difference in the structure of proteins and
polysaccharides?
a. Only polysaccharides are comprised of repeating units of cytosine, adenine, guanine,
and thymine.
b. Only proteins are formed from amino acids joined by peptide bonds.
c. Only polysaccharides can be folded and twisted to very specific shapes.
d. Only proteins can be large molecules with thousands of subunits.
3.
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Biochemistry Test Review
1. What are the steps of the scientific method?
2. Define control:
3. Define independent variable:
4. Define dependent variable:
5. How many variables should you have per experiment?
6. Define monomer:
7. Define polymer:
8. What are the four most commonly found elements in macromolecules?
9. Define dehydration synthesis (condensation), and draw a picture demonstrating it:
10. Define hydrolysis, and draw a picture demonstrating it:
11. What macromolecule is an enzyme?
12. Describe the function of an enzyme, including what it does to the activation energy.
13. What does “denature” mean, and name three conditions that would cause it:
14. What happens to an enzyme after the reaction?
15. What two macromolecules’ main functions are to store energy?
16. What are the monomers and polymers called in:
a. Carbohydrates
i. Monomer ii. Polymer b. Proteins
i. Monomer –
ii. Polymer c. Nucleic Acids
i. Monomer 14
17. What are the main functions of the following?
a. Carbohydrates:
b. Lipids:
c. Proteins:
d. Nucleic Acids:
18. Draw a monomer of the following:
a. Carbohydrate
b. Lipid
c. Protein
d. Nucleic Acid
19. Draw and label an enzyme substrate complex. Include: enzyme, substrate, active site, product.
20. Which macromolecule are hormones made of?
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