SBI4U: Biochemistry Test
Mr. Dykstra
Name: ____________
/60
1.
Sugars are soluble in water because they:
A.
contain polar regions.
B.
are slightly acidic.
C.
ionize completely.
D.
are not as dense as water.
2.
Ribose, deoxyribose, glucose, and fructose are all similar because they are all
A.
polysaccharides.
B.
fatty acids.
C.
monosaccharides.
D.
disaccharides.
3.
Which association is NOT correct?
A.
nucleic acid - genes
B.
carbohydrate - enzymes
C.
fats - long-term storage of energy
D.
proteins - cell membrane
4.
Glycogen is
A.
a monosaccharide used for quick energy.
B.
a protein found in cell membranes.
C.
a polysaccharide used as stored energy.
D.
a fat found in margarine.
5.
A fatty acid which contains a large number of double bonds is
A.
saturated.
B.
unsaturated.
C.
a neutral fat.
D.
a triglyceride.
6.
A nucleotide is composed of:
A.
a phosphate base, a sugar and a nitrate group.
B.
two or more polypeptides in quaternary association.
C.
a nitrogenous base, an amino acid and a sulphate group.
D.
a nitrogenous base, a sugar and a phosphate group.
7.
The bond which holds together complementary base pairs in a D.N.A. molecule is called
A.
ionic.
B.
covalent.
C.
hydrogen.
D.
disulphide.
8.
Which one of the following bases is a component of RNA but not of DNA?
A.
uracil
B.
thymine
C.
adenine
D.
guanine
9.
There are several bonds involved in the formation of complete/functional proteins. After the
amino acids are liked together during translation, hydrogen bonds cause the polypeptide to twist into a
helix or coil. What level of protein structure is represented by the helical coil?
A.
primary
B.
secondary
C.
tertiary
D.
quaternary
10.
A straight chain (linear sequence) of amino acids in a polypeptide is called a
A.
tertiary structure.
B.
primary structure.
C.
globular structure.
D.
secondary structure.
11.
A functional group is composed of nitrogen and two hydrogens. It has the group name:
A.
amino (amine)
B.
hydroxide.
C.
acid.
D.
carboxyl.
12.
Which one of the following substances is a protein?
A.
Glucose
B.
Collagen
C.
Glycogen
D.
Cholesterol
13.
In water, hydrogen bonding occurs between hydrogen and
A.
an oxygen atom in the same molecule.
B.
an oxygen atom in a different molecule.
C.
a hydrogen atom in the same molecule.
D.
a hydrogen atom in a different molecule.
14.
Which of the following is not a property of water?
A.
is an organic molecule
B.
is a polar molecule
C.
contains hydrogen bonds
D.
is more dense as a liquid than a solid
15.
Chemical analysis of a substance shows that it contains amino groups and carboxyl groups.
Which one of the following would this substance most likely be?
A.
A fat.
B.
An enzyme.
C.
A cofactor.
D.
A carbohydrate.
16.
In DNA, the purines and pyrimidines are:
A.
purines, C,G: pyrimidines, A,T.
B.
purines, G,A: pyrimidines, C,T.
C.
bound to phosphates.
D.
both part of every nucleotide.
17.
Which of the following is not a lipid molecule?
A.
Amylopectin
B.
Stearic acid
C.
Cholesterol
D.
Wax
18.
Polymers common in organisms are
A.
starch
B.
glycogen
C.
cellulose
D.
all of the above
19.
Steroids
A.
are not naturally found within living systems
B.
have a chemical structure similar to cholesterol
C.
include the sex hormones and aldosterone
D.
two of the above
20.
Organic compounds having the same molecular formulas but different structural arrangements are
examples of
A.
isotopes.
B.
isomers.
C.
isoelectrics.
D.
isotonic
21.
A dipole occurs when
A.
two atoms with an electronegativity difference bond.
B.
electrons are transferred from one atom to another.
C.
two atoms of the same electronegativity bond.
D.
electrons are shared equally between two atoms.
22.
When chemical bonds are formed, energy is
A.
absorbed and the process is exothermic.
B.
released and the process is exothermic.
C.
absorbed and the process is endothermic.
D.
released and the process is endothermic.
E.
either released or absorbed, depending on the bond.
23.
When compounds form, the resulting structure is
A.
more stable and has a state of lower energy.
B.
less stable and has a state of lower energy.
C.
more stable and has a state of higher energy.
D.
less stable and has a state of higher energy.
24.
The reason why all chemical bonds are formed is to
A.
fill inner orbitals with electrons.
B.
split lone pairs into bonding electrons.
C.
cause electrons to reach a more stable configuration.
D.
cause electrons to be transferred.
25.
Which of the following is the weakest?
A.
covalent bonds
B.
ionic bonds
C.
London forces
D.
hydrogen bonds
E.
dipole-dipole forces
26.
Which is true about the enzyme-substrate complex in a reaction ?
A.
It acts as a catalyst
B.
It is a stable compound
C.
It always forms products.
D.
It possesses more energy than the reactants or the products.
27.
The minimum amount of energy required to bring about a reaction is called
A.
enthalpy.
B.
entropy.
C.
activation energy.
D.
reaction mechanism energy.
28.
In a chemical reaction, the use of a catalyst results in a decrease in the
A.
activation energy
B.
potential energy of the reactants
C.
heat of reaction
D.
amount of products
29.
A chemical reaction that joins two molecules with the loss of a molecule of water is called:
A.
A hydrolysis reaction
B.
An acid-base reaction
C.
An oxidation-reduction reaction.
D.
A condensation reaction
30.
Which of the following is an example of a disaccharide?
A.
Ribose
B.
Lactose
C.
Glucose
D.
Fructose
Diagrams: [12]
1. Identify the molecules below:
a)
[1 each]
b)
c)
d)
2. Identify the class or family of each molecule below:
a)
b)
c)
d)
3. Name the functional groups indicated below:
a)
[1 each]
[1 each]
b)
4. Diagram all the possible hydrogen bonds between these nitrogen bases. [1]
BONUS: Name the bases.
Short Answer Questions:
[20]
1.
Compare starch and cellulose in structure and function. [3]
2.
Briefly describe the four levels of protein structure. [4]
3.
List three biological uses for lipids. [3]
4.
Enzymes are protein catalysts in the body, and have many important roles. Briefly
describe:
a) two commercial uses for enzymes
[2]
b) how their function is affected by natural factors. [2]
c) how their function can be regulated by the body. [3]
5.
Use the sugars below to show how sucrose can be formed by a condensation reaction.
What type of linkage is this? [3]