AP Bio FRQs Exam; Questions & Answers 100% Solved
Describe the role of carbon in biological systems. Correct answer-The response indicates
that carbon is used to build biological macromolecules such as carbohydrates, proteins, nucleic
acids, and lipids.
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.
Correct 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.
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. Correct 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.
Provide reasoning with evidence based on the composition of biological macromolecules to
support your claim. Correct answer-The response indicates that nucleic acids (DNA, RNA,
or nucleotides) and amino acids (polypeptides, or proteins) contain nitrogen.
Identify the process used to form the covalent peptide bonds that join amino acids into a
polypeptide. Correct answer-The response indicates that the process that joins amino
acids into a polypeptide is a dehydration synthesis OR a condensation reaction.
, AP Bio FRQs Exam; Questions & Answers 100% Solved
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. Correct 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.
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. Correct answer-The response indicates primary and tertiary structure.
Explain how the amino acid substitution shown in Figure 1 is most likely to affect the function of
Receptor X. Correct 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.
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. Correct 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.
Determine the external concentration of substance L that will result in one-half of the maximal
entry rate. Correct 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.
, AP Bio FRQs Exam; Questions & Answers 100% Solved
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. Correct 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.
Describe the biological need for cells to be surrounded by a membrane that is selectively
permeable for different materials. Correct 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.
Explain how the model shows selective permeability of the membrane to specific ions.
Correct 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).
Describe the characteristics of the phospholipid bilayer that permit small hydrophobic lipid
molecules to pass directly across the membrane. Correct answer-The response indicates
that the interior of a phospholipid bilayer is hydrophobic, which allows small hydrophobic
molecules to diffuse across the membrane.
Based on the model, explain whether the molecules shown crossing the membrane require
energy to do so. Correct answer-The response indicates that energy is not required for
Describe the role of carbon in biological systems. Correct answer-The response indicates
that carbon is used to build biological macromolecules such as carbohydrates, proteins, nucleic
acids, and lipids.
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.
Correct 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.
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. Correct 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.
Provide reasoning with evidence based on the composition of biological macromolecules to
support your claim. Correct answer-The response indicates that nucleic acids (DNA, RNA,
or nucleotides) and amino acids (polypeptides, or proteins) contain nitrogen.
Identify the process used to form the covalent peptide bonds that join amino acids into a
polypeptide. Correct answer-The response indicates that the process that joins amino
acids into a polypeptide is a dehydration synthesis OR a condensation reaction.
, AP Bio FRQs Exam; Questions & Answers 100% Solved
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. Correct 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.
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. Correct answer-The response indicates primary and tertiary structure.
Explain how the amino acid substitution shown in Figure 1 is most likely to affect the function of
Receptor X. Correct 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.
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. Correct 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.
Determine the external concentration of substance L that will result in one-half of the maximal
entry rate. Correct 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.
, AP Bio FRQs Exam; Questions & Answers 100% Solved
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. Correct 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.
Describe the biological need for cells to be surrounded by a membrane that is selectively
permeable for different materials. Correct 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.
Explain how the model shows selective permeability of the membrane to specific ions.
Correct 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).
Describe the characteristics of the phospholipid bilayer that permit small hydrophobic lipid
molecules to pass directly across the membrane. Correct answer-The response indicates
that the interior of a phospholipid bilayer is hydrophobic, which allows small hydrophobic
molecules to diffuse across the membrane.
Based on the model, explain whether the molecules shown crossing the membrane require
energy to do so. Correct answer-The response indicates that energy is not required for
