Download AP Biology Biochemistry Review

AP Biology Biochemistry Review
1 About 25 of the 92 natural elements are known to be essential to life. Which
four of these 25 elements make up approximately 96% of living matter?
A
B
C
D
E
carbon, sodium, chlorine, nitrogen
carbon, sulfur, phosphorus, hydrogen
oxygen, hydrogen, calcium, sodium
carbon, hydrogen, nitrogen, oxygen
carbon, oxygen, sulfur, calcium
2 Di!erent atomic forms of an element contain the same number of protons
but a di!erent number of neutrons. What are these di!erent atomic forms
called?
A
B
C
D
E
ions
isotopes
neutronic atoms
isomers
radioactive atoms
3 A covalent bond is likely to be polar when
A
B
C
D
E
the two atoms sharing electrons are equally electronegative.
the two atoms sharing electrons are of the same element.
one of the atoms sharing electrons is much more electronegative
than the other atom.
it is between two atoms that are both very strong electron
acceptors.
the two atoms sharing electrons are di!erent elements.
4 A van der Waals interaction is the weak attraction between
A
B
C
D
E
the electrons of one molecule and the electrons of a nearby
molecule.
the nucleus of one molecule and the electrons of a nearby
molecule.
a polar molecule and a nearby nonpolar molecule.
a nonpolar molecule and a nearby molecule that is also nonpolar.
a polar molecule and a nearby molecule that is also polar.
5 Which of the following describes any reaction that has attained chemical
equilibrium?
A
The concentration of the reactants equals the concentration of the
products.
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AP Biology Biochemistry Review
B
C
D
E
The rate of the forward reaction is equal to the rate of the reverse
reaction.
All of the reactants have been converted to the products of the
reaction.
All of the products have been converted to the reactants of the
reaction.
Both the forward and the reverse reactions have stopped with no
net e!ect on the concentration of the reactants and the products.
6 What do cohesion, surface tension, and adhesion have in common with
reference to water?
A
B
C
D
E
All increase when temperature increases.
All are produced by ionic bonding.
All have to do with nonpolar covalent bonds.
All are properties related to hydrogen bonding.
C and D only
7 Why does ice float in liquid water?
A
B
C
D
E
The liquid water molecules have more kinetic energy and thus
support the ice.
The ionic bonds between the molecules in ice prevent the ice from
sinking.
The crystalline lattice of ice causes it to be denser than liquid
water.
Ice always has air bubbles that keep it afloat.
Hydrogen bonds stabilize and keep the molecules of ice farther
apart than the water molecules of liquid water.
8 Hydrophobic substances such as vegetable oil are
A
B
C
D
E
nonpolar substances that have an attraction for water molecules.
polar substances that repel water molecules.
nonpolar substances that repel water molecules.
polar substances that have an a"nity for water.
charged molecules that hydrogen-bond with water molecules.
9 Organic chemistry is a science based on the study of
A
B
C
D
functional groups.
vital forces interacting with matter.
water and its interaction with other kinds of molecules.
inorganic compounds.
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AP Biology Biochemistry Review
E
carbon compounds.
10 Which property of the carbon atom gives it compatibility with a greater
number of di!erent elements than any other type of atom?
A
B
C
D
E
Carbon has 6 to 8 neutrons.
Carbon forms ionic bonds.
Carbon has a valence of 4.
A and C only
A, B, and C
11 Which of the following is (are) true about the carbon atoms present in all
organic molecules?
A
B
C
D
E
They were incorporated into organic molecules by plants.
They were processed into sugars through photosynthesis.
They are ultimately derived from carbon dioxide.
Only A and C are correct.
A, B, and C are correct.
12 Which two functional groups are always found in amino acids?
A
B
C
D
E
ketone and aldehyde
carboxyl and amino
carbonyl and carboxyl
phosphate and sulfhydryl
hydroxyl and aldehyde
13 Which of the following is not one of the four major groups of
macromolecules found in living organisms?
A
B
C
D
E
carbohydrates
lipids
proteins
nucleic acids
glucose
14 Polymers of polysaccharides, fats, and proteins are all synthesized from
monomers by which process?
A
B
C
connecting monosaccharides together (condensation reactions)
the addition of water to each monomer (hydrolysis)
ionic bonding of the monomers
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D
E
the removal of water (dehydration reactions)
the formation of disulfide bridges between monomers
15 Which of the following best summarizes the relationship between
dehydration reactions and hydrolysis?
A
B
C
D
E
Dehydration reactions can occur only after hydrolysis.
Hydrolysis creates monomers, and dehydration reactions break
down polymers.
Dehydration reactions assemble polymers, and hydrolysis breaks
down polymers.
Hydrolysis only occurs in the urinary system, and dehydration
reactions only occur in the digestive tract.
A and C are correct.
16 A molecule with the chemical formula C16H32O16 is probably a
A
B
C
D
E
lipid.
carbohydrate.
protein.
nucleic acid.
hydrocarbon.
17 Which of the following are polysaccharides?
A
B
C
D
E
glycogen
starch
chitin
A and B only
A, B, and C
18 Which of the following is (are) true for the class of large biological
molecules known as lipids?
A
B
C
D
E
They are insoluble in water.
They are an important constituent of cell membranes.
They contain twice as much energy as an equivalent weight of
polysaccharide.
Only A and B are correct.
A, B, and C are correct.
19 What maintains the secondary structure of a protein?
A
peptide bonds
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B
C
D
E
disulfide bonds
hydrogen bonds
ionic bonds
phosphodiester bonds
20 Which of the following descriptions best fits the class of molecules known
as nucleotides?
A
B
C
D
E
a
a
a
a
a
nitrogenous base and a phosphate group
nitrogenous base, a phosphate group, and a pentose sugar
nitrogenous base and a pentose sugar
phosphate group and an adenine or uracil
pentose sugar and a purine or pyrimidine
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Answer Key: AP Biology Biochemistry Review
Question
Key
1
D
2
B
3
C
4
E
5
B
6
D
7
E
8
C
9
E
10
C
11
E
12
B
13
E
14
D
15
C
16
B
17
E
18
E
19
C
20
B
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