Bio 314 Exam 2 Questions and All
Correct Answers 2025-2026 Updated.
What are the specificity properties for membrane transporters vs membrane channels for their
respective transported solute? - Answer Transporters have specific binding sites; channels
allow substance in based on ion charges or size of molecules
If a stimulus causes the membrane of the neuron below to depolarize to -50 mV, would action
potential be generated? - Answer No
What is the main function of lysosomes? - Answer Protein degradation
Imagine you are studying the transport of proteins into mitochondria. You engineer a
mitochondrial protein to remove its sorting signal and see that it is now found in the cytosol.
This tells you that the sorting signal is...? - Answer Necessary for targeting to mitochondria
True or False: Transport of proteins into the nucleus does not require energy. - Answer False
What is one difference between protein transport into the nucleus and transport into the
mitochondria? - Answer Proteins have to be unfolded for transport into mitochondria,
whereas folded proteins can be transported into the nucleus,
Imagine you are studying a protein with multiple transmembrane regions that is inserted into
the ER membrane. The protein has a typical cleavable N-terminal ER signal sequence. Which
side of the membrane would you expect the N-terminus to be? - Answer ER lumen
You have identified a yeast mutant that accumulates a vacuolar protein in the Golgi. Which
trafficking step would you conclude is blocked? - Answer Golgi → Vacuole
What can happen if there are improperly folded proteins in the ER? - Answer Chaperone
proteins prevent them from entering vesicles; signals gene expression change and produces
more chaperone proteins; ER stress inducing apoptosis
What is an example of constitutive secretion? - Answer Secretion of cell wall materials in
plants
What prevents lysosomal hydrolases from degrading important proteins in the cytosol? -
Answer Compartmentalization and hydrolases reduce activity in the neutral pH of the
cytosol
, Depolarization is to excitatory receptor response as hyperpolarization is to... - Answer
Inhibitory receptor response
If the solute concentration inside a cell is 300 mM and the solute concentration outside of the
cell is 800 mM, which direction will water move by osmosis? - Answer Out of the cell
Which of the following would you predict requires ATP? - Answer Active transport of Na+ out
of a cell
They exist in open and closed conformations
They are selective for one type of ion
Their activities can be measured by the patch clamp technique
They are transmembrane proteins
What are they? - Answer Ion channels
Cells can transport molecules against their concentration gradient by coupling transport to... -
Answer ATP hydrolysis
input of light energy
transport of another molecule down its concentration gradient
True or False: Transporters can perform active transport only. - Answer False
True or False: Facilitated diffusion (passive transport) is mediated by integral membrane
proteins. - Answer True
Patch-clamp analysis can be used - Answer To measure current through an ion channel
An action potential is generated in a nerve cell once the plasma membrane is... - Answer
depolarized to the threshold potential
True or False: Most psychoactive drugs work by binding to transmitter-gated ion channels and
opening them. (not voltage-gated) - Answer True
Which of the following are found in plant cells but not in mammalian cells? - Answer Cell
wall
Correct Answers 2025-2026 Updated.
What are the specificity properties for membrane transporters vs membrane channels for their
respective transported solute? - Answer Transporters have specific binding sites; channels
allow substance in based on ion charges or size of molecules
If a stimulus causes the membrane of the neuron below to depolarize to -50 mV, would action
potential be generated? - Answer No
What is the main function of lysosomes? - Answer Protein degradation
Imagine you are studying the transport of proteins into mitochondria. You engineer a
mitochondrial protein to remove its sorting signal and see that it is now found in the cytosol.
This tells you that the sorting signal is...? - Answer Necessary for targeting to mitochondria
True or False: Transport of proteins into the nucleus does not require energy. - Answer False
What is one difference between protein transport into the nucleus and transport into the
mitochondria? - Answer Proteins have to be unfolded for transport into mitochondria,
whereas folded proteins can be transported into the nucleus,
Imagine you are studying a protein with multiple transmembrane regions that is inserted into
the ER membrane. The protein has a typical cleavable N-terminal ER signal sequence. Which
side of the membrane would you expect the N-terminus to be? - Answer ER lumen
You have identified a yeast mutant that accumulates a vacuolar protein in the Golgi. Which
trafficking step would you conclude is blocked? - Answer Golgi → Vacuole
What can happen if there are improperly folded proteins in the ER? - Answer Chaperone
proteins prevent them from entering vesicles; signals gene expression change and produces
more chaperone proteins; ER stress inducing apoptosis
What is an example of constitutive secretion? - Answer Secretion of cell wall materials in
plants
What prevents lysosomal hydrolases from degrading important proteins in the cytosol? -
Answer Compartmentalization and hydrolases reduce activity in the neutral pH of the
cytosol
, Depolarization is to excitatory receptor response as hyperpolarization is to... - Answer
Inhibitory receptor response
If the solute concentration inside a cell is 300 mM and the solute concentration outside of the
cell is 800 mM, which direction will water move by osmosis? - Answer Out of the cell
Which of the following would you predict requires ATP? - Answer Active transport of Na+ out
of a cell
They exist in open and closed conformations
They are selective for one type of ion
Their activities can be measured by the patch clamp technique
They are transmembrane proteins
What are they? - Answer Ion channels
Cells can transport molecules against their concentration gradient by coupling transport to... -
Answer ATP hydrolysis
input of light energy
transport of another molecule down its concentration gradient
True or False: Transporters can perform active transport only. - Answer False
True or False: Facilitated diffusion (passive transport) is mediated by integral membrane
proteins. - Answer True
Patch-clamp analysis can be used - Answer To measure current through an ion channel
An action potential is generated in a nerve cell once the plasma membrane is... - Answer
depolarized to the threshold potential
True or False: Most psychoactive drugs work by binding to transmitter-gated ion channels and
opening them. (not voltage-gated) - Answer True
Which of the following are found in plant cells but not in mammalian cells? - Answer Cell
wall
