BIO 1201 EXAM 2 QUESTIONS &
ANSWERS
What is the function of cholesterol? - Correct Answer ✔✔ Stabilization of the
phospholipids
Which of the following best describes the structure of a biological membrane? - Correct
Answer ✔✔ two layers of phospholipids with proteins either crossing the layers or on
the surface of the layers
Which of these cannot rapidly pass directly through the phospholipids of the plasma
membrane? - Correct Answer ✔✔ Water, Glucose, and Hydrogen
Which of the following factors does not affect membrane permeability? - Correct Answer
✔✔ The polarity of membrane phospholipids
How can a lipid be distinguished from a sugar? - Correct Answer ✔✔ Lipids are mostly
non polar
True or false? Osmosis is a type of diffusion. - Correct Answer ✔✔ True
Which of the following particles could diffuse easily through a cell membrane? - Correct
Answer ✔✔ Oxygen (O2)
True or false? The water-soluble portion of a phospholipid is the polar head, which
generally consists of a glycerol molecule linked to a phosphate group. - Correct Answer
✔✔ True
What distinguishes facilitated diffusion from simple diffusion? - Correct Answer ✔✔
Membrane proteins help move molecules across the membrane.
Which of the following transporters does not use passive transport to move molecules
across a membrane? - Correct Answer ✔✔ Sodium-potassium pump
True or false? Active transport differs from passive transport in that active transport
does not require an input of energy. - Correct Answer ✔✔ False
Which membrane protein would be used to move glucose across a membrane from a
region of higher concentration to a region of lower concentration? - Correct Answer ✔✔
Transporter
Which of the following statements is true about the net movement of an ion across a
membrane by passive diffusion through a membrane channel? - Correct Answer ✔✔
, The charge on the other side of the membrane is generally the opposite of the ion's
charge.
True or false? During active transport through the sodium-potassium pump, ATP
hydrolysis provides the energy to pump three sodium ions into the cell for every two
potassium ions pumped out of the cell. - Correct Answer ✔✔ False
Lactose transport by membrane proteins occurs under conditions in which the
concentration of lactose inside the cell is higher than the concentration outside the cell.
What type of transport is used to move lactose into the cell? - Correct Answer ✔✔
Active transport
If the concentration of phosphate in the cytosol is 2.0 mM and the concentration of
phosphate in the surrounding fluid is 0.1 mM, how could the cell increase the
concentration of phosphate in the cytosol? - Correct Answer ✔✔ Active Transport
The movement of glucose into a cell against a concentration gradient is most likely to be
accomplished by which of the following? - Correct Answer ✔✔ cotransport of the
glucose with a proton or sodium ion that was pumped across the membrane using the
energy of ATP hydrolysis
Active and passive transport of solutes across a membrane typically differ in which of
the following ways? - Correct Answer ✔✔ Active transport always involves the utilization
of cellular energy, whereas passive transport does not require cellular energy.
A reaction involving an increase in Enthalpy and an increase in Entropy will always be?
- Correct Answer ✔✔ It can be either depending on the exact values
During a chemical reaction you observe that there is an increase in enthalpy and a
decrease in the entropy. Based on these observations please indicate whether the
following statement about this reaction is true or false. The products of this reaction are
more organized than the reactants. - Correct Answer ✔✔ True
A spontaneous reaction occuring at 250K and with a 2.0Kcal decrease in entropy must
have which of the following changes in enthalpy? - Correct Answer ✔✔ -600 Kcal
How can one increase the rate of a chemical reaction? - Correct Answer ✔✔ add a
catalyst
A molecule which is bound to a site other than the active site of an enzyme and causes
a decrease in the rate of the reaction would be best described as a - Correct Answer
✔✔ Non-competitive inhibitor
The most abundant lipids in most membranes are - Correct Answer ✔✔ Phospholipids
ANSWERS
What is the function of cholesterol? - Correct Answer ✔✔ Stabilization of the
phospholipids
Which of the following best describes the structure of a biological membrane? - Correct
Answer ✔✔ two layers of phospholipids with proteins either crossing the layers or on
the surface of the layers
Which of these cannot rapidly pass directly through the phospholipids of the plasma
membrane? - Correct Answer ✔✔ Water, Glucose, and Hydrogen
Which of the following factors does not affect membrane permeability? - Correct Answer
✔✔ The polarity of membrane phospholipids
How can a lipid be distinguished from a sugar? - Correct Answer ✔✔ Lipids are mostly
non polar
True or false? Osmosis is a type of diffusion. - Correct Answer ✔✔ True
Which of the following particles could diffuse easily through a cell membrane? - Correct
Answer ✔✔ Oxygen (O2)
True or false? The water-soluble portion of a phospholipid is the polar head, which
generally consists of a glycerol molecule linked to a phosphate group. - Correct Answer
✔✔ True
What distinguishes facilitated diffusion from simple diffusion? - Correct Answer ✔✔
Membrane proteins help move molecules across the membrane.
Which of the following transporters does not use passive transport to move molecules
across a membrane? - Correct Answer ✔✔ Sodium-potassium pump
True or false? Active transport differs from passive transport in that active transport
does not require an input of energy. - Correct Answer ✔✔ False
Which membrane protein would be used to move glucose across a membrane from a
region of higher concentration to a region of lower concentration? - Correct Answer ✔✔
Transporter
Which of the following statements is true about the net movement of an ion across a
membrane by passive diffusion through a membrane channel? - Correct Answer ✔✔
, The charge on the other side of the membrane is generally the opposite of the ion's
charge.
True or false? During active transport through the sodium-potassium pump, ATP
hydrolysis provides the energy to pump three sodium ions into the cell for every two
potassium ions pumped out of the cell. - Correct Answer ✔✔ False
Lactose transport by membrane proteins occurs under conditions in which the
concentration of lactose inside the cell is higher than the concentration outside the cell.
What type of transport is used to move lactose into the cell? - Correct Answer ✔✔
Active transport
If the concentration of phosphate in the cytosol is 2.0 mM and the concentration of
phosphate in the surrounding fluid is 0.1 mM, how could the cell increase the
concentration of phosphate in the cytosol? - Correct Answer ✔✔ Active Transport
The movement of glucose into a cell against a concentration gradient is most likely to be
accomplished by which of the following? - Correct Answer ✔✔ cotransport of the
glucose with a proton or sodium ion that was pumped across the membrane using the
energy of ATP hydrolysis
Active and passive transport of solutes across a membrane typically differ in which of
the following ways? - Correct Answer ✔✔ Active transport always involves the utilization
of cellular energy, whereas passive transport does not require cellular energy.
A reaction involving an increase in Enthalpy and an increase in Entropy will always be?
- Correct Answer ✔✔ It can be either depending on the exact values
During a chemical reaction you observe that there is an increase in enthalpy and a
decrease in the entropy. Based on these observations please indicate whether the
following statement about this reaction is true or false. The products of this reaction are
more organized than the reactants. - Correct Answer ✔✔ True
A spontaneous reaction occuring at 250K and with a 2.0Kcal decrease in entropy must
have which of the following changes in enthalpy? - Correct Answer ✔✔ -600 Kcal
How can one increase the rate of a chemical reaction? - Correct Answer ✔✔ add a
catalyst
A molecule which is bound to a site other than the active site of an enzyme and causes
a decrease in the rate of the reaction would be best described as a - Correct Answer
✔✔ Non-competitive inhibitor
The most abundant lipids in most membranes are - Correct Answer ✔✔ Phospholipids
