Biol 212 Exam 1 & 2 Questions and
Answers
GIVEN: The red blood cell membrane is impermeable to mannitol, but is permeable to
both water and glucose. Red blood cells will shrink the most when immersed in:
ANSWERS a hyperosmotic mannitol solution
During hemoglobin metabolism, the breakdown products of heme become part of:
ANSWERS bile
If potassium were at equilibrium across the cell membrane, then what would be the
direction of the electrochemical driving force acting on potassium? ANSWERS
there is no electrochemical force at equilibrium
Mice from a certain lab strain remain healthy as long as you feed them regularly and do
not let them exercise. After they eat, their blood glucose level rises slightly and then
declines to a homeostatic level. However, if these mice fast or exercise at all, their blood
glucose drops dangerously. Which hypothesis best explains their problem?
ANSWERS The mice lack glucagon receptors on their cells.
The chordae tendineae are needed for the appropriate functioning of the:
ANSWERS bicuspid or mitral valve
A person suffers from a chronically dry mouth. What type of drug would be BEST to
treat this disorder? ANSWERS parasympathetic agonist
Which of the following is NOT true about the sympathetic nervous system?
ANSWERS It emerges from the cranial and sacral regions of the CNS.
Anesthetics cross the cell membranes in nerve tissue relatively easily. Therefore,
anesthetics have a: ANSWERS high partition coefficient
A scientist is studying the passive movement of chemicals into a cell. He measures the
rate at which two chemicals diffuse into a cell, as a function of their external
concentration. Chemical A's diffusion is directly proportional to the extracellular
concentration but eventually reaches a transport maximum, while Chemical B's rate of
transport continues to be directly proportional to external concentration.
How can one explain the differences in these diffusion rates? ANSWERS
Chemical A is moving by facilitated diffusion, while Chemical B is diffusing through the
phospholipids or through a channel.
, Given that oubain blocks the Na+/K+ pump, how would this drug affect glucose
transport in the small intestine? ANSWERS Compared to normal, less glucose
would be absorbed from the lumen of the small intestine.
You have a 0.022 OsM solution of glucose. This solution is: ANSWERS hypo-
osmotic to human cells.
One long-term consequence of diabetes mellitus is that the basement membrane below
the endothelial cells of capillary walls becomes thicker. If this happens, according to
Fick's Law, the rate of diffusion of substances from the blood to the tissues will:
ANSWERS decrease
The primary cation inside the cell is: ANSWERS potassium
Under low oxygen conditions, __________ must unload its electrons to allow glycolysis
to continue its production of ATP: ANSWERS NADH
A 10% starch solution is separated from pure water by a membrane which is
impermeable to starch. What will happen? ANSWERS Net water movement will
eventually stop as a result of an opposing hydrostatic pressure.
The end products of the Krebs cycle include all of the following except: ANSWERS
pyruvate
If the concentration of bicarbonate ions (HCO3-) in the ICF is 10 mM and the
concentration in the ECF is 28 mM, what would be the equilibrium potential for
bicarbonate? ANSWERS -27 mV
The GLUT family of molecules are: ANSWERS carrier proteins for the facilitated
diffusion of glucose
Which is a TRUE statement about the resting membrane potential in a typical neuron?
ANSWERS The sodium-potassium pump maintains the sodium and potassium
concentration gradients; having these concentration gradients is critical to maintaining a
steady resting membrane potential.
Given: the atomic mass of calcium is 40.1 g/mole, and the atomic mass of chloride is
35.5 g/mole. What % solution is a 3.0 OsM CaCl2 solution? ANSWERS 11.1%
A molecule that is similar in structure to a ligand, binds to the normal ligand's receptor
on a target cell, and produces a similar biological response in the cell is called a(n):
ANSWERS agonist
The sodium ion (Na+) becomes more hydrated than the potassium ion (K+) because:
ANSWERS the sodium ion has a greater density of surface charge
Answers
GIVEN: The red blood cell membrane is impermeable to mannitol, but is permeable to
both water and glucose. Red blood cells will shrink the most when immersed in:
ANSWERS a hyperosmotic mannitol solution
During hemoglobin metabolism, the breakdown products of heme become part of:
ANSWERS bile
If potassium were at equilibrium across the cell membrane, then what would be the
direction of the electrochemical driving force acting on potassium? ANSWERS
there is no electrochemical force at equilibrium
Mice from a certain lab strain remain healthy as long as you feed them regularly and do
not let them exercise. After they eat, their blood glucose level rises slightly and then
declines to a homeostatic level. However, if these mice fast or exercise at all, their blood
glucose drops dangerously. Which hypothesis best explains their problem?
ANSWERS The mice lack glucagon receptors on their cells.
The chordae tendineae are needed for the appropriate functioning of the:
ANSWERS bicuspid or mitral valve
A person suffers from a chronically dry mouth. What type of drug would be BEST to
treat this disorder? ANSWERS parasympathetic agonist
Which of the following is NOT true about the sympathetic nervous system?
ANSWERS It emerges from the cranial and sacral regions of the CNS.
Anesthetics cross the cell membranes in nerve tissue relatively easily. Therefore,
anesthetics have a: ANSWERS high partition coefficient
A scientist is studying the passive movement of chemicals into a cell. He measures the
rate at which two chemicals diffuse into a cell, as a function of their external
concentration. Chemical A's diffusion is directly proportional to the extracellular
concentration but eventually reaches a transport maximum, while Chemical B's rate of
transport continues to be directly proportional to external concentration.
How can one explain the differences in these diffusion rates? ANSWERS
Chemical A is moving by facilitated diffusion, while Chemical B is diffusing through the
phospholipids or through a channel.
, Given that oubain blocks the Na+/K+ pump, how would this drug affect glucose
transport in the small intestine? ANSWERS Compared to normal, less glucose
would be absorbed from the lumen of the small intestine.
You have a 0.022 OsM solution of glucose. This solution is: ANSWERS hypo-
osmotic to human cells.
One long-term consequence of diabetes mellitus is that the basement membrane below
the endothelial cells of capillary walls becomes thicker. If this happens, according to
Fick's Law, the rate of diffusion of substances from the blood to the tissues will:
ANSWERS decrease
The primary cation inside the cell is: ANSWERS potassium
Under low oxygen conditions, __________ must unload its electrons to allow glycolysis
to continue its production of ATP: ANSWERS NADH
A 10% starch solution is separated from pure water by a membrane which is
impermeable to starch. What will happen? ANSWERS Net water movement will
eventually stop as a result of an opposing hydrostatic pressure.
The end products of the Krebs cycle include all of the following except: ANSWERS
pyruvate
If the concentration of bicarbonate ions (HCO3-) in the ICF is 10 mM and the
concentration in the ECF is 28 mM, what would be the equilibrium potential for
bicarbonate? ANSWERS -27 mV
The GLUT family of molecules are: ANSWERS carrier proteins for the facilitated
diffusion of glucose
Which is a TRUE statement about the resting membrane potential in a typical neuron?
ANSWERS The sodium-potassium pump maintains the sodium and potassium
concentration gradients; having these concentration gradients is critical to maintaining a
steady resting membrane potential.
Given: the atomic mass of calcium is 40.1 g/mole, and the atomic mass of chloride is
35.5 g/mole. What % solution is a 3.0 OsM CaCl2 solution? ANSWERS 11.1%
A molecule that is similar in structure to a ligand, binds to the normal ligand's receptor
on a target cell, and produces a similar biological response in the cell is called a(n):
ANSWERS agonist
The sodium ion (Na+) becomes more hydrated than the potassium ion (K+) because:
ANSWERS the sodium ion has a greater density of surface charge
