BIOCHEMISTRY STUDY GUIDE
Vocabulary words at end of worksheet (roman numeral IX)
I.
Organic chemistry
1. Characteristics of carbon that contribute to its ability to form an immense
diversity of organic molecules include its:
a. Tendency to form covalent bonds
b. Ability to bond with up to four other atoms
c. Capacity to form single, double, or triple bonds
d. Ability to bond together to form extensive, branched or
unbranched carbon skeletons
e. All of the above
2. Organic compounds
a. Can only be synthesized in a lab
b. Always contain nitrogen
c. Always contain carbon
d. Are synthesized by cells
e. Both c and d
3. Organic compounds that make up living things are ultimately produced by
plants in a process known as:
a. Cell respiration
b. Fermentation
c. Photosynthesis
d. Dehydration synthesis
e. Hydrolysis
4. What element forms the backbone of organic molecules? _____________
5. Remember, there is a huge variation in living things both within a species
and between species. The differences are due to the large variety of
carbon-based molecules (organic compounds), especially proteins. List
three reasons why carbon is responsible for the huge diversity of
biological molecules. Essentially, how many kinds of atoms serve as
building blocks to make the infinite variety of organic compounds?
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II.
Monomers and polymers
1. Which of the following statements is/are true of the monomers and
polymers found in living organisms?
a. Each type of organism has a unique set of monomers used to
form its polymers
b. All types of organisms use approximately the same set of
monomers to form their polymers.
c. Each type of organism has its own polymers, some of which are
different from those found in other organisms.
d. All of the polymers found in all organisms re identical.
e. Both b and c are true
2. Monomers can be joined together by a process called dehydration
synthesis. Which of the following statements is/are true of this process?
a. One monomer loses a hydrogen atom, and the other loses a
hydroxyl group.
b. Electrons are shared between atoms of the joined monomer
c. Water (H2O) is formed as the monomers are joined.
d. Covalent bonds are formed between the monomers.
e. All of the above are true
3. The result of dehydration synthesis can be reversed by
a. A condensation reaction
b. A hydrolysis reaction
c. Digestion
d. Polymerization
e. Both b and c
4. How many molecules of water are needed to completely hydrolyze a
polymer that is 10 monomers?
5. After you eat a slice of apple, the amino acid monomers in the protein of
the apple are used to make new and different proteins in your body. Name
the reaction(s) that must take place.
III.
Carbohydrates
1. The molecular formula of most monosaccharides represents a multiple of:
a. CH3O
b. CH2O
c. CHO
d. CHO2
e. CHO3
2. Carbohydrates contain the elements ____________, ______________,
And _________________________
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3. Propanol and isopropanol are isomers. This means that they have:
a. The same molecular formula but different chemical properties
b. Different molecular formula but the same chemical properties
c. The same molecular formula and the same chemical properties
d. The same number of carbon atoms but different number of
oxygen and hydrogen atoms
4. Which of the following statements is/are true of monosaccharides
a. They are simple sugars
b. They belong to a class of organic compounds called carbohydrates
c. They serve as monomers for the more complex carbohydrates, the
polysaccharides
d. Serve as an immediate source of fuel (energy) for living cells
e. All of the above
5. Sucrose is formed
a. From two glucose molecules
b. From two monosaccharides by dehydration synthesis
c. When ionic bonds link two monosaccharides
d. When water molecules are added to two monosaccharides
e. A, b, and c
6. Sucrose, maltose, and lactose
a. Are carbohydrates
b. Are disaccharides
c. Are isomers
d. Link together by ionic bonds to form starch
e. Both a and b
7. Glycogen
a. Contains glucose molecules
b. Contains C, H, and O atoms
c. Is a polysaccharide
d. Is a carbohydrate animals use to store energy
8. The storage form of carbohydrates in plants is
a. Starch
b. Glycogen
c. Cellulose
d. Fiber
e. Sucrose
9. Suppose a cell lost its supply of simple sugars. Which macromolecule
could the cell no longer produce? Explain
10. Explain the relation between monomers and polymers using
polysaccharides as an example.
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11. What carbohydrate forms the cell wall of plants?
12. In animals, where is glycogen stored?
IV.
Lipids
1. The main characteristic of lipids includes
a. Being hydrophilic
b. Being hydrophobic
c. Being polar (linked by polar covalent bonds)
d. Being nonpolar (linked by nonpolar covalent bonds)
e. Both b and d
2. A fat
a.
b.
c.
d.
e.
Consists of three fatty acids attached to a glycerol
Is hydrophobic
Plays a role in energy storage
Also referred to as a triglyceride
All of the above
3. Fatty acids with double bonds between some of their carbons are said to
be
a. Unsaturated
b. Saturated
c. Completely hydrogenated
d. Triglycerides
e. Monoglycerides
4. Unsaturated fats
a. Have kinks at double bonds causing a bend in hydrocarbon chain
b. Pack more closely together than saturated fats
c. Are solid at room temperature
d. Come from animals
e. b, c, and d
5. Saturated fats
a. Contain at least one double bond between carbons
b. Contain the maximum number of hydrogen’s
c. Are derived from plants
d. Are the healthier type of fat
e. b, c, and d
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6. One way to convert an oil into a substance that is solid at room
temperature is to:
a. Add hydrogen’s, decreasing the number of double bonds in the
molecule
b. Remove water, causing a dehydration synthesis reaction to occur
c. Remove hydrogen’s, increasing the number of double bonds
d. Put in the refrigerator, when unsaturated fats cool, double bonds
form and the fats solidify
e. Add water and shake vigorously
7. If you were to add olive oil to your food as part of a diet to lower your risk
of atherosclerosis, you would use olive oil that
a. Was liquid at room temperature
b. Was hydrogenated
c. Was modified to be solid at room temperature
d. Had lard added to it
e. None of the above
8. If you want to promote the development of heart disease you would eat a
diet high in
a. Fiber
b. Protein
c. Saturated fats
d. Sugars
e. Complex carbohydrates
9. Suppose you wanted to make margarine using plant oil. How would you
alter the oil molecules to make the oil solid at room temperature?
a. Attach more fatty acids to each glycerol
b. Reduce the number of fatty acids attached to each glycerol
c. Add hydrogen’s to change the double bonds in the fatty acids to
single bonds
d. Use a larger glycerol
e. Add a phosphate group to the glycerol
10. Diets high in animal products may increase the risk of heart disease and
cancer. This is apparently due to the fact that
a. Most animal fats are saturated
b. Most animal fats are hydrogenated oils
c. Most animal fats are unsaturated
d. Most animal products contain high levels of triglycerides
e. Both a and d
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11. Lipids are important in animal cells as
a. Energy-containing molecules
b. Components of cell membranes
c. Steroids and hormones
d. Insulation and cushioning
e. All of the above
12. A phospholipid is composed of
a. One glycerol molecule linked to three fatty acid molecules
b. One glycerol molecule linked to three phosphate groups
c. One glycerol molecule linked to two fatty acid molecules and a
phosphate group
d. One fatty acid molecule linked to three glycerol molecules
e. One fatty acid molecule linked to one glycerol molecule and two
phosphate groups
13. Which if any of the following substances is not a lipid?
a. Wax
b. Cholesterol
c. Steroids
d. Cellulose
e. All are lipids
14. A major type of lipid in cell membrane is:
a. Wax
b. Triglyceride
c. Steroids
d. Phospholipid
e. Cellulose
15. Which of the following statements is/are true about waxes?
a. They are lipids
b. They are more hydrophobic than fat
c. They are used by some insects and plants for protection
d. They are nonpolar
e. All of the above are true
16. What molecule serves as the template or starting point for making all other
steroids?
a. Wax
b. Cholesterol
c. Testosterone
d. Cellulose
e. All are lipids
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V.
Proteins
1. Describe three different functions of proteins
2. Amino acids can be distinguished from one another by
a. The number of R groups found on the amino acid molecules
b. The chemical properties of the R group
c. The type of bond between the R group and the rest of the amino
acid molecule
d. The chemical properties of the amino group and carboxyl group
3. Draw an amino acid and label the amino group, carboxyl group, R-group,
and alpha carbon
4. Glucose molecules are to starch as ______________ are to proteins
a. Oils
b. Amino acids
c. Fatty acids
d. Waxes
e. Lards
5. Peptide bonds
a. Hold the polypeptide chains of complex proteins together
b. Form between fatty acids
c. Are formed by hydrolysis reactions
d. Link amino acids
e. None of the above
6. What are a dipeptide, tripeptide, and polypeptide?
7. Describe a peptide bond. Draw and label
8. Which of the following may be affected by the denaturation of a protein?
a. The shape of the protein
b. The function of the protein
c. The number of amino acids in a protein
d. The solubility of the protein in water
e. A, b, and d
9. Which of the following factors can result in the denaturation of a protein?
a. Heat
b. Change in pH
c. Chemicals that destroy hydrogen bonds
d. Change in salt concentration
e. All of the above
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10. The ___________________ structure of a protein consists of a chain of
amino acids assembled in a specific order
a. Primary
b. Secondary
c. Tertiary
d. Quaternary
e. None of the above
11. Which of the following is an example of secondary structure in a protein?
a. A particular amino acid sequence
b. An alpha helix
c. A globular shape
d. A pleated sheet
e. Both b and d
12. The tertiary structure of a polypeptide refers to
a. Its size
b. The presence of pleated sheets
c. Its three dimensional structure
d. The amino acids of which it is made
e. The number of R groups it contains
13. A protein containing more than one polypeptide chain exhibits
___________ level(s) of protein structure
a.
b.
c.
d.
e.
One
Two
Three
Four
Five
14. A scientist suspects that the food in an ecosystem may have been
contaminated with radioactive nitrogen over a period of months. Which of
the following substances could be examined for radioactivity to test the
hypothesis?
a. The cell wall of plants living in this ecosystem
b. The hair produced by humans living in this ecosystem
c. The sugars produced during photosynthesis by plants growing in
the ecosystem
d. The cholesterol in the cell membranes of organisms living in this
ecosystem
e. Any of the above
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VI.
Nucleic acids
1. Genetic information is encoded in the
a. Quaternary structure of a protein
b. Sequence of nucleotides in DNA
c. Degree of saturation in fatty acids
d. Length of glycogen
e. Linear sequence of amino acids in a polypeptide
2. Nucleotides
a. Contain nitrogenous bases
b. Contain sugar molecules
c. Contain phosphate groups
d. Can be linked together to form a double helix
e. All of the above
3. DNA differs from RNA because DNA
a. Contains thymine in place of uracil
b. Consists of a single rather than a double polynucleotide strand
c. Contains pentose rather than hexose sugars
d. Contains phosphate groups
e. All of the above
4. Which of the following substances contain nitrogen?
a. Amino acids
b. Hair
c. Nucleotides
d. All of the above
e. Both a and c
VII. Organic compounds
5. Which, if any, of the following choices does not properly pair an organic
compound with one of its building blocks (monomer).
a. Polysaccharide-monosaccharide
b. Fat-fatty acid
c. Nucleic acid-glycerol
d. Protein-amino acid
e. All of these are paired correctly
6. A rival company is distributing a new wonder food. The researchers in
your company determine that the wonder food contains only carbon,
hydrogen, and oxygen. At this point the researchers
a. Can say with certainty that the food is not made of proteins
b. Can say with certainty that the food is not made of nucleic acids
c. Can say the food can only be a carbohydrate
d. Cannot eliminate the notion that the food may be a fat
e. A and b
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7. The glucose produced by a plant during photosynthesis is used to make the
carbohydrate, proteins, fats, and nucleic acids of the plant. Which
statement is true about the process of converting sugars into other
molecules?
a. Glucose contains all of the elements needed to produce these
other molecules
b. Glucose contains all of the elements needed to produce the
carbohydrates, but other elements must come from the soil if the
plant is to produce fats, proteins, and nucleic acids
c. Glucose contains all of the elements needed to produce the
carbohydrates and fats, but other elements must come from the
soil if the plant is to produce proteins, and nucleic acids
d. Glucose contains all of the elements needed to produce the
carbohydrates and nucleic acids, but other elements must come
from the soil if the plant is to produce fats and proteins
e. None of these substances can be produced from glucose alone
8. Name and give one example of each of the four major groups of organic
compounds found in living things
9. Describe the function of each group of organic compounds in living
things.
VIII.
Structure of organic compounds
A. The following questions are based on the 15 molecules illustrated in figure 5.8 below.
Each molecule may be used once, more than once, or not at all.
1. Which of the molecules are isomers?
2. Which of the combinations could be linked together to form a nucleotide?
3. Which of the molecules are carbohydrates?
4. Explain the bend (kink) in molecule # 5. Do you think it would be a liquid or solid at
room temperature?
5. Which molecule acts as a building block of polypeptides?
6. Which molecule is an amino acid with a hydrophobic R group?
7. Which molecules could form a peptide bond as a result of dehydration synthesis?
8. Which molecules could form a fat as a result of dehydration synthesis?
9. Which molecule is the sugar found in RNA?
10. Which is a disaccharide form of a carbohydrate?
11. Which molecule needs to see s therapist? (Both polar and nonpolar)
12. Which molecule is a polymer of a monosaccharide?
13. Which two molecules join to form a fat?
14. Which molecule is a saturated fatty acid?
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IX.
Vocabulary
1. Monomer
2. Polymer
3. Carbohydrate
4. Monosaccharide
5. Disaccharide
6. Polysaccharide
7. Isomer
8. Dehydration synthesis
(condensation reaction)
9. Hydrolysis
10. Polymerization
11. Conformation
12. Denaturation
13. Polypeptide
14. Dipeptide
15. Peptide bond
16. Lipid
17. Saturated fatty acid
18. Unsaturated fatty acid
19. Hydrogenated
20. Amino acid
21. Protein
22. Nucleotide
23. Nucleic acid
24. DNA
25. RNA
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