FINAL EXAM FOR : AP PSYCHOLOGY WITH QUESTIONS AND
DETAILED ANSWERS. 2025
QUESTION: Explain how, when the membranes are fused, the polar parts of the phospholipids from one
cell will interact with the phospholipids from the other cell and how the nonpolar parts of the
phospholipids from one cell will interact with the phospholipids from the other cell. - ANSWER-The
response indicates that the polar part of the phospholipids from one cell will align or interact with the
polar parts of the phospholipids from the other cell, and nonpolar parts of the phospholipids from one
cell will align or interact with nonpolar parts of the phospholipids from the other cell.
QUESTION: Make a claim about the most immediate effect on the fused B-cancer cells if the fused cells
are transferred to a growth medium that lacks a source of nitrogen. - ANSWER-The response indicates
that the cells will die OR that they will be unable to synthesize DNA and RNA/nucleic acids/nucleotides
and amino.
QUESTION: Provide reasoning with evidence based on the composition of biological macromolecules to
support your claim. - ANSWER-The response indicates that nucleic acids (DNA, RNA, or nucleotides) and
amino acids (polypeptides, or proteins) contain nitrogen.
QUESTION: Identify the process used to form the covalent peptide bonds that join amino acids into a
polypeptide. - ANSWER-The response indicates that the process that joins amino acids into a polypeptide
is a dehydration synthesis OR a condensation reaction.
,QUESTION: The change in the amino acid sequence illustrated in Figure 1 caused a change in the shape
of Receptor X. Based on the R groups of the original and substituted amino acids, explain why Receptor X
changed shape. - ANSWER-The response indicates that two amino acids with charged or ionic or
hydrophilic R-groups were replaced by two amino acids with uncharged or nonpolar or hydrophobic R-
groups.
QUESTION: Using the template below that represents the four levels of protein structure, place an X on
each level that is expected to be altered as a result of the amino acid substitutions shown in Figure 1. -
ANSWER-The response indicates primary and tertiary structure.
QUESTION: Explain how the amino acid substitution shown in Figure 1 is most likely to affect the
function of Receptor X. - ANSWER-The response indicates that because function is determined by shape,
the function of receptor X is likely to change OR that the structural change might alter the binding of the
molecule to receptor X OR that the structural change might alter the ability of receptor X to cause a
cellular response.
QUESTION: Identify the most likely mode of transport across the membrane for substance L. Explain
how information provided helps determine the most likely mode of transport. - ANSWER-The response
indicates that substance L most likely crosses the membrane by active transport. The response indicates
that the cells maintain an intracellular concentration of 120 mM, which is always greater than the
concentration of substance L in the culture medium.
QUESTION: Determine the external concentration of substance L that will result in one-half of the
maximal entry rate. - ANSWER-The response indicates that the external concentration of substance L
that will result in one-half of the maximal entry rate is a value other than one between 31 mM and 34
mM.
,QUESTION: Predict the likely effect on the ability of substance L to enter the cells if substance L is
attached to a large protein instead of free in the culture. - ANSWER-The response indicates that
substance L will be unable to enter the cells if it is attached to a large protein OR the response indicates
that substance L will be unable to enter the cells if it is attached to a large protein unless there is a
specific cell membrane receptor for the protein.
QUESTION: Describe the biological need for cells to be surrounded by a membrane that is selectively
permeable for different materials. - ANSWER-The response indicates that a cell membrane separates the
internal environment of the cell from the external environment OR that a cell membrane that is
selectively permeable can help to regulate what molecules move between the differing environments
inside and outside of a cell.
QUESTION: Explain how the model shows selective permeability of the membrane to specific ions. -
ANSWER-The response indicates that a membrane channel protein is selective for a specific kind of ion
because only one of the two kinds of ion represented can pass through the channel. The response also
indicates that ions cannot simply cross directly between the phospholipids of the membrane (although a
small lipid-soluble molecule can).
QUESTION: Describe the characteristics of the phospholipid bilayer that permit small hydrophobic lipid
molecules to pass directly across the membrane. - ANSWER-The response indicates that the interior of a
phospholipid bilayer is hydrophobic, which allows small hydrophobic molecules to diffuse across the
membrane.
QUESTION: Based on the model, explain whether the molecules shown crossing the membrane require
energy to do so. - ANSWER-The response indicates that energy is not required for the substances to cross
the membrane because the substances are being passively transported from a region of higher
concentration to a region of lower concentration.
, QUESTION: Describe the role of oxygen in cellular respiration. - ANSWER-The response indicates that
oxygen is the terminal acceptor of electrons that have passed through the electron transport chain.
QUESTION: Describe the relationship between the concentration of glucose in the culture medium and
the ATP concentration in the cells. - ANSWER-The response indicates that the concentration of glucose
appears to have little or no effect on the ATP concentration of the cells.
QUESTION: In a further experiment, the researchers add a compound to the cell growth medium that
both binds and releases protons (H+) and also passes through lipid membranes. Predict the effect of this
added compound on ATP production by the cells. Justify your prediction. - ANSWER--The response
indicates that the amount of ATP produced will decrease OR that no ATP will be produced.
-The response indicates that the compound is more likely to bind protons where the protons are in
greater concentration, in the intermembrane space. It also does not indicate that if the compound then
carries the protons across the inner membrane to the matrix, there will no longer be a proton
concentration/pH/electrochemical gradient across the inner membrane, and protons will not flow
through and power the ATP synthase enzymes.
QUESTION: Depending on the organism, the optimal pH for enolase to catalyze its reaction is between
6.5 and 8.0. Describe how a pH below or above this range is likely to affect enolase and its catalytic
ability. - ANSWER-The response indicates that a pH below or above this range will most likely cause
enolase to denature/change its shape and be less efficient or unable to catalyze the reaction.
QUESTION: Identify the appropriate negative control the researchers most likely used when measuring
the reaction rate in the presence of each organism's enolase. - ANSWER-The response indicates that the
DETAILED ANSWERS. 2025
QUESTION: Explain how, when the membranes are fused, the polar parts of the phospholipids from one
cell will interact with the phospholipids from the other cell and how the nonpolar parts of the
phospholipids from one cell will interact with the phospholipids from the other cell. - ANSWER-The
response indicates that the polar part of the phospholipids from one cell will align or interact with the
polar parts of the phospholipids from the other cell, and nonpolar parts of the phospholipids from one
cell will align or interact with nonpolar parts of the phospholipids from the other cell.
QUESTION: Make a claim about the most immediate effect on the fused B-cancer cells if the fused cells
are transferred to a growth medium that lacks a source of nitrogen. - ANSWER-The response indicates
that the cells will die OR that they will be unable to synthesize DNA and RNA/nucleic acids/nucleotides
and amino.
QUESTION: Provide reasoning with evidence based on the composition of biological macromolecules to
support your claim. - ANSWER-The response indicates that nucleic acids (DNA, RNA, or nucleotides) and
amino acids (polypeptides, or proteins) contain nitrogen.
QUESTION: Identify the process used to form the covalent peptide bonds that join amino acids into a
polypeptide. - ANSWER-The response indicates that the process that joins amino acids into a polypeptide
is a dehydration synthesis OR a condensation reaction.
,QUESTION: The change in the amino acid sequence illustrated in Figure 1 caused a change in the shape
of Receptor X. Based on the R groups of the original and substituted amino acids, explain why Receptor X
changed shape. - ANSWER-The response indicates that two amino acids with charged or ionic or
hydrophilic R-groups were replaced by two amino acids with uncharged or nonpolar or hydrophobic R-
groups.
QUESTION: Using the template below that represents the four levels of protein structure, place an X on
each level that is expected to be altered as a result of the amino acid substitutions shown in Figure 1. -
ANSWER-The response indicates primary and tertiary structure.
QUESTION: Explain how the amino acid substitution shown in Figure 1 is most likely to affect the
function of Receptor X. - ANSWER-The response indicates that because function is determined by shape,
the function of receptor X is likely to change OR that the structural change might alter the binding of the
molecule to receptor X OR that the structural change might alter the ability of receptor X to cause a
cellular response.
QUESTION: Identify the most likely mode of transport across the membrane for substance L. Explain
how information provided helps determine the most likely mode of transport. - ANSWER-The response
indicates that substance L most likely crosses the membrane by active transport. The response indicates
that the cells maintain an intracellular concentration of 120 mM, which is always greater than the
concentration of substance L in the culture medium.
QUESTION: Determine the external concentration of substance L that will result in one-half of the
maximal entry rate. - ANSWER-The response indicates that the external concentration of substance L
that will result in one-half of the maximal entry rate is a value other than one between 31 mM and 34
mM.
,QUESTION: Predict the likely effect on the ability of substance L to enter the cells if substance L is
attached to a large protein instead of free in the culture. - ANSWER-The response indicates that
substance L will be unable to enter the cells if it is attached to a large protein OR the response indicates
that substance L will be unable to enter the cells if it is attached to a large protein unless there is a
specific cell membrane receptor for the protein.
QUESTION: Describe the biological need for cells to be surrounded by a membrane that is selectively
permeable for different materials. - ANSWER-The response indicates that a cell membrane separates the
internal environment of the cell from the external environment OR that a cell membrane that is
selectively permeable can help to regulate what molecules move between the differing environments
inside and outside of a cell.
QUESTION: Explain how the model shows selective permeability of the membrane to specific ions. -
ANSWER-The response indicates that a membrane channel protein is selective for a specific kind of ion
because only one of the two kinds of ion represented can pass through the channel. The response also
indicates that ions cannot simply cross directly between the phospholipids of the membrane (although a
small lipid-soluble molecule can).
QUESTION: Describe the characteristics of the phospholipid bilayer that permit small hydrophobic lipid
molecules to pass directly across the membrane. - ANSWER-The response indicates that the interior of a
phospholipid bilayer is hydrophobic, which allows small hydrophobic molecules to diffuse across the
membrane.
QUESTION: Based on the model, explain whether the molecules shown crossing the membrane require
energy to do so. - ANSWER-The response indicates that energy is not required for the substances to cross
the membrane because the substances are being passively transported from a region of higher
concentration to a region of lower concentration.
, QUESTION: Describe the role of oxygen in cellular respiration. - ANSWER-The response indicates that
oxygen is the terminal acceptor of electrons that have passed through the electron transport chain.
QUESTION: Describe the relationship between the concentration of glucose in the culture medium and
the ATP concentration in the cells. - ANSWER-The response indicates that the concentration of glucose
appears to have little or no effect on the ATP concentration of the cells.
QUESTION: In a further experiment, the researchers add a compound to the cell growth medium that
both binds and releases protons (H+) and also passes through lipid membranes. Predict the effect of this
added compound on ATP production by the cells. Justify your prediction. - ANSWER--The response
indicates that the amount of ATP produced will decrease OR that no ATP will be produced.
-The response indicates that the compound is more likely to bind protons where the protons are in
greater concentration, in the intermembrane space. It also does not indicate that if the compound then
carries the protons across the inner membrane to the matrix, there will no longer be a proton
concentration/pH/electrochemical gradient across the inner membrane, and protons will not flow
through and power the ATP synthase enzymes.
QUESTION: Depending on the organism, the optimal pH for enolase to catalyze its reaction is between
6.5 and 8.0. Describe how a pH below or above this range is likely to affect enolase and its catalytic
ability. - ANSWER-The response indicates that a pH below or above this range will most likely cause
enolase to denature/change its shape and be less efficient or unable to catalyze the reaction.
QUESTION: Identify the appropriate negative control the researchers most likely used when measuring
the reaction rate in the presence of each organism's enolase. - ANSWER-The response indicates that the
