BS161 Exam | Questions solved 100%
Correct/Verified Solutions
Which molecule would most likely require a transport protein to cross the plasma membrane
of a red blood cell?
a. CO2
b. C6H12O6
c. Larger, more polar molecules are less able to cross a membrane than small,
nonpolar molecules.
d. H2O
e. O2 - ANSWER b. C6H12O6
The plasma membranes of some plant cells use transport proteins to move protons out of
the cell against their concentration gradient. This is an example of:
a. facilitated diffusion
b. simple diffusion
c. passive transport
d. endocytosis
e. active transport - ANSWER e. active transport
Which substance could most easily cross a synthetic membrane composed of phospholipids but
not proteins?
a. water
b. oxygen
c. glucose
d. sodium ions - ANSWER b. oxygen
,Glucose molecules move into cells limiting the intestine by moving up/against their
concentration gradient. This movement of glucose is driven by the movement of sodium ions
into the cells down/with their concentration gradient. The above describes an example of:
a. secondary active transport
b. facilitated diffusion
c. simple diffusion
d. primary active transport - ANSWER a. secondary active transport
The action of sodium-potassium pumps that hydrolyze ATP in order to move sodium ions out
of a cell and potassium ions into a cell is an example of:
a. facilitated diffusion
b. simple diffusion
c. secondary active transport
d. primary active transport - ANSWER d. primary active transport
Water molecules move into the cytosol of a cell placed in a hypotonic solution using:
a. simple diffusion
b. primary active transport
c. osmosis
d. secondary active transport - ANSWER c. osmosis
Sodium ions move through sodium channels in a synthetic membrane using:
a. facilitated diffusion
b. secondary active transport
c. simple diffusion
d. primary active transport - ANSWER a. facilitated diffusion
, Sodium molecules move randomly around a solution of sodium chloride in water,
frequently colliding with other sodium ions and chloride ions. This is an example of:
a. secondary active transport
b. diffusion
c. osmosis
d. primary active transport - ANSWER b. diffusion
Which lipid composition option has the least membrane fluidity?
a. phospholipids with long-chain, unsaturated fatty acids.
b. phospholipids with long-chain, saturated fatty acids.
c. phospholipids with short-chain, saturated fatty acids.
d. phospholipids with short-chain, unsaturated fatty acids. - ANSWER b. phospholipids with
long-chain, saturated fatty acids.
Suppose you are studying the transport of a certain polar molecule across the plasma
membrane of cells in culture. Over a period of time, you measure the concentration of the
polar molecule and outside of the cells. You find that the concentration of the molecule is
higher inside the cell and is gradually increasing. You also measure the ATP concentration inside
the cell and find that it is decreasing. Which of the following is probably responsible for the
transport of the polar substance into the cell?
a. active transport
b. facilitated diffusion
c. simple diffusion
d. endocytosis - ANSWER a. active transport
Turgor pressure is the result of:
a. all of these choices are correct.
b. water accumulation within a cell.
c. the rigidity of the plasma membrane.
Correct/Verified Solutions
Which molecule would most likely require a transport protein to cross the plasma membrane
of a red blood cell?
a. CO2
b. C6H12O6
c. Larger, more polar molecules are less able to cross a membrane than small,
nonpolar molecules.
d. H2O
e. O2 - ANSWER b. C6H12O6
The plasma membranes of some plant cells use transport proteins to move protons out of
the cell against their concentration gradient. This is an example of:
a. facilitated diffusion
b. simple diffusion
c. passive transport
d. endocytosis
e. active transport - ANSWER e. active transport
Which substance could most easily cross a synthetic membrane composed of phospholipids but
not proteins?
a. water
b. oxygen
c. glucose
d. sodium ions - ANSWER b. oxygen
,Glucose molecules move into cells limiting the intestine by moving up/against their
concentration gradient. This movement of glucose is driven by the movement of sodium ions
into the cells down/with their concentration gradient. The above describes an example of:
a. secondary active transport
b. facilitated diffusion
c. simple diffusion
d. primary active transport - ANSWER a. secondary active transport
The action of sodium-potassium pumps that hydrolyze ATP in order to move sodium ions out
of a cell and potassium ions into a cell is an example of:
a. facilitated diffusion
b. simple diffusion
c. secondary active transport
d. primary active transport - ANSWER d. primary active transport
Water molecules move into the cytosol of a cell placed in a hypotonic solution using:
a. simple diffusion
b. primary active transport
c. osmosis
d. secondary active transport - ANSWER c. osmosis
Sodium ions move through sodium channels in a synthetic membrane using:
a. facilitated diffusion
b. secondary active transport
c. simple diffusion
d. primary active transport - ANSWER a. facilitated diffusion
, Sodium molecules move randomly around a solution of sodium chloride in water,
frequently colliding with other sodium ions and chloride ions. This is an example of:
a. secondary active transport
b. diffusion
c. osmosis
d. primary active transport - ANSWER b. diffusion
Which lipid composition option has the least membrane fluidity?
a. phospholipids with long-chain, unsaturated fatty acids.
b. phospholipids with long-chain, saturated fatty acids.
c. phospholipids with short-chain, saturated fatty acids.
d. phospholipids with short-chain, unsaturated fatty acids. - ANSWER b. phospholipids with
long-chain, saturated fatty acids.
Suppose you are studying the transport of a certain polar molecule across the plasma
membrane of cells in culture. Over a period of time, you measure the concentration of the
polar molecule and outside of the cells. You find that the concentration of the molecule is
higher inside the cell and is gradually increasing. You also measure the ATP concentration inside
the cell and find that it is decreasing. Which of the following is probably responsible for the
transport of the polar substance into the cell?
a. active transport
b. facilitated diffusion
c. simple diffusion
d. endocytosis - ANSWER a. active transport
Turgor pressure is the result of:
a. all of these choices are correct.
b. water accumulation within a cell.
c. the rigidity of the plasma membrane.
