Download Study Guide Test 3 * Organic Chemistry

Bio A - Biochemistry
Name ____________________________________
Study guide for – Biochemistry and enzymes (Full Test after Thanksgiving Break)
General information:
- What makes a molecule an organic compound?
Contains carbon AND hydrogen
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____hydrocarbons______ are a subgroup of organic compounds that ONLY contain carbon and hydrogen.
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Inorganic molecules may contain __carbon________ OR hydrogen but will not contain both.
Carbon is a really good atom for building large molecules because it can make ____4____ covalent bonds
When we look at molecules, we use the terms monomer and polymer. Define these terms
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Monomer ______single unit of a molecule ________________________
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Polymer _______multiple monomers bond together to form a polymer chain____________
Macromolecules
Complete the following chart
Monomer name
Polymer Name
Elements these
contain
Primary Function
Carbohydrates
Monosaccharide
Polysaccharide
CHO
Energy, short term energy storage
(animals) Structure (plant cell walls)
Lipids
Four components:
CHO but
much less O
than carbs
Long term energy storage
Cell membranes (phospholipids)
3 fatty acids
1 glycerol
Triglyceride (not
really a true
polymer since it is
not a chaing
Proteins
Amino acids
Polypeptide
CHONS
Structure, enzymes, antibodies,
hormones
Nucleic Acids
Nucleotides
Nucleic acids
(DNA and RNA
CHONP
Genetic code – how to assemble
proteins!
Bio A - Biochemistry
Name ____________________________________
Building and breaking:
1.
What chemical reaction is used to build all the above molecules? Is water added or removed from the
reactants?
Dehydration Synthesis – water removed to build up
2. What chemical reaction breaks them all down? Is water added or subtracted from the reactants?
Hydrolysis – water put in to break down
Carbohydrates
1. Define:
a. Monosaccharide -________single sugar______________________________________
i. Examples – glucose, fructose
b. Polysaccharide - __________multiple sugars linked together___________________
i. Examples – Starch, Cellulose, Glycogen
2. Draw the basic shape of a glucose molecule. You need to be able to recognize this molecule!
See notes – look for hexagon
3. Complete the following chart
Polysaccharide
Who makes it
Starch
Plant
Cellulose
Plant
Glycogen
Animal
Main function
Energy storage
Structure – cell walls
Short term energy storage
4. When we eat starch, what does our digestive system do to the starch molecules?
Hydrolysis  glucose which can enter our blood
a. Once absorbed in the blood, what does our body do with the glucose?
1. Use it right away as energy for cells
2. Store it for later  dehydration synthesis into glycogen
5. What is different about cellulose when we consume it? In other words, how is it different than starch?
Cant hydrolysize it so it wont give us energy BUT it will help with digestion.
Bio A - Biochemistry
Name ____________________________________
Lipids
1. What is the primary role of lipids in living systems?
Long term energy storage
Plasma membrane structure - phospholipid
2. Why do lipids contain so much potential energy?
Lot of C-H bonds
3. Draw the basic structure of a triglyceride. You need to know how to recognize this!
See below right
4. Which of the following lipid molecules are
saturated? Which is unsaturated?
Unsaturated have C=C double bonds while saturated are only single bonds
5. Which of these molecules are more likely to be from a plant?
Unsaturated fats - oils
6. What makes a fat “unsaturated”?
Does not contain all the hydrogens it can hold due to the C=C double bonds
7. Which type of fat (saturated or unsaturated) would be most likely to be a liquid at room temperature?
Why?
Unsaturated – double bonds cause bends in chain which makes them less tightly
packed
Bio A - Biochemistry
Name ____________________________________
8. How does the process of “hydrogenation” turn a liquid oil into a solid fat?
Take an oil – add hydrogens to break C=C double bonds, now it is more saturated and
more solid-ish. Think about margarine which is made from vegetable oil.
9. What characteristic of lipids (fats oils and waxes) make it not likely to mix with water?
NON- polar. Fatty acids by themselves can mix but Triglycerides are neutral.
Proteins
1. What are the two super important roles of proteins in living systems?
a. __Structure
b. ___Enzymes___________
2. What do we link together to make proteins (polypeptides)?
Amino acids
3. How many different amino acids are there? 20
4. Define
a. Essential amino acids : Amino acids we MUST consume
b. Non-essential amino acids : Amino acids we can synthesize in our bodies from essential amino
acids
5. Draw the basic structure of an amino acid. Label – carboxyl group, amino group, R side chain.
6. Show how a peptide bond would form between the two amino acids below
Bio A - Biochemistry
Name ____________________________________
7. What role does the R side chain play in how the polypeptide fold up into a functional protein?
The characteristics of the side chain (polar or non-polar) will determine how they interact and cause the
polypeptide to fold up into a complex structure (2nd, 3rd and 4th levels of structure).
8. What is meant by the phrase “a proteins’ function is determined by its shape”
Without a specific shape, it cannot do its job
9. What happens to the function of a protein if it loses its’ shape?
ditto
10. What levels of structure in a protein are affected by denaturation?
2, 3 and 4th as these are the levels held together by weak bonds (like hydrogen). The primary level is
strong covalent bonds (peptide bonds) and will not be affected.
Enzymes:
1. An enzyme is a type of protein whose job is to speed up rate of chemical reactions
2. What is the activation energy of a chemical reaction? What effect do enzymes have on the activation
energy?
Amount of energy need to start a chemical reaction – enzymes lower it!
Bio A - Biochemistry
Name ____________________________________
3. There are several ways to deactivate an enzyme. For each thing listed below, describe HOW it prevents
an enzyme from doing its job. Explain how the following environmental factors can effect enzyme
reaction rates.
a. Temperature – heat breaks weak bonds that hold protein shape together. Active site changes thus
enzyme cant function
b. pH – same as temp but either too strong a base or acid results in denaturation. Also, best pH not
always 7!
c. Substrate Concentration
Increased substrate will increase concentration to a point where the enzyme cant work
any faster.
Make sure you know why these things happen!!!
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Draw an enzyme reaction and label the enzyme, substrate, active site, enzyme-substrate complex, products
and competitive inhibitor. DON’T WORRY ABOUT INHIBITOR!!!!
Bio A - Biochemistry
-
Name ____________________________________
The human body has MANY different chemical reactions to perform. Can it use the same enzyme for
each? Why or why not? Use vocab!!
No, only one substrate per enzyme – has to match active site.
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T/F: All human enzymes prefer neutral pH. Explain your answer including any exceptions (enzymes AND
body parts) from your notes.
False, stomach enzymes work best in acidic pH. Intestinal enzymes in basic environment.
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How is the 3D shape of an enzyme important to its function? What happens when an enzyme denatures?
This question has been answered many time already in this study guide.
Also know:
- the individual parts of both the nucleotide and the amino acid
Vocabulary: These are all in your notes/textbook
Denature
Enzyme-substrate complex
Active site
Monomer
Polymer
Variable R group
Activation energy
Amino Group
Substrate
Carboxyl Group
Enzyme
Nucleotide
Amino Acid
Monosaccharide
Glycerol
Fatty acids
Triglyceride
Bio A - Biochemistry
Name ____________________________________