NURS 534 Advanced Physiology Cell and Signal
transduction questions with verified answers
. Describe the difference between water soluble ligands and lipid
soluble ligands (e.g., steroid hormones); focus on how they activate
their respective signal transduction systems. Ans✓✓✓ Water soluble
ligands are unable to pass freely through the plasma membrane due to
their polarity and must bind to an extracellular domain of a cell-surface
receptor
Then it initiates a pathway to create a new ligand/messenger on the
inside of the cell; there needs to be a middle-man
Lipid soluble ligands use intracellular receptors-- steroid, TH, retinoids.
Lipid soluble ligands cannot be stored, can pass through membranes, so
must be made from soluble precursors as needed
"Mail delivery," able to deliver messages directly
. Why is it important for glucose to be transported via a secondary
transport process and using a carrier-mediated protein into and out of
a small intestinal epithelial cell? Ans✓✓✓ Na+ is the "gas" for SGLT2
GLUT2 is a "free ride" for glucose out of the cell
Glucose needs to be transported because it is too big to fit through cell
membrane otherwise
Because of this, there is faster utilization of glucose when needed,
because insulin is not needed
* A network of membranes and vesicles.
,* The Golgi apparatus packages proteins into vesicles
* The vesicles break off from the Golgi complex and migrate to a variety
of intracellular and extracellular destinations.
* The Golgi complex is more prominent in some cells, particularly those
that secrete proteins. (ex. immunoglobulins)
Golgi complex = packaging center/transport facility Ans✓✓✓ Golgi
complex
• ______ occur with "passive" electrical activity (movement of sodium
(Na+), potassium (K+), chloride (Cl‐ ) across the plasma membrane).
• ________ result in small, transient changes in membrane potential.
• _______vary in terms of their strength and duration, and the signal
will not travel very far (the graded potential degrades over time and
space). Later (Weeks 5 and 6) we will contrast this with action
potentials.
• Action potential represent greater changes in the electrical p Ans✓✓✓
Graded potentials
• A measure of the osmotic pressure gradient determined by the water
potential between two solutions.
• The two solutions are separated by a semipermeable membrane.
• Determines the direction of diffusion.
, • The solutes that can't cross the membrane influence the tonicity. The
solutes that can freely cross the membrane don't influence tonicity
because they will equilibrate to have equal concentrations on either
side of the membrane. Ans✓✓✓ Tonicity
• Actin filaments (i.e., microfilaments) - components of the contractile
apparatus
• Intermediate filaments (e.g., keratin filaments, neurofilaments)
• Microtubules - important for intracellular transport, support the
movement of chromosomes during mitosis, and allow the movement of
cilia and flagella. Ans✓✓✓ Cytoskeleton
• An ion‐transporting enzyme in the plasma membrane.
• This solute pump is important for sodium (Na+) and potassium (K+)
movement (active transport).
• Both ions are moving against their concentration gradients (i.e.,
Na+moving out of the cell and K+moving into the cell), which requires
energy. Ans✓✓✓ Na+‐K+‐ATPase pump
transduction questions with verified answers
. Describe the difference between water soluble ligands and lipid
soluble ligands (e.g., steroid hormones); focus on how they activate
their respective signal transduction systems. Ans✓✓✓ Water soluble
ligands are unable to pass freely through the plasma membrane due to
their polarity and must bind to an extracellular domain of a cell-surface
receptor
Then it initiates a pathway to create a new ligand/messenger on the
inside of the cell; there needs to be a middle-man
Lipid soluble ligands use intracellular receptors-- steroid, TH, retinoids.
Lipid soluble ligands cannot be stored, can pass through membranes, so
must be made from soluble precursors as needed
"Mail delivery," able to deliver messages directly
. Why is it important for glucose to be transported via a secondary
transport process and using a carrier-mediated protein into and out of
a small intestinal epithelial cell? Ans✓✓✓ Na+ is the "gas" for SGLT2
GLUT2 is a "free ride" for glucose out of the cell
Glucose needs to be transported because it is too big to fit through cell
membrane otherwise
Because of this, there is faster utilization of glucose when needed,
because insulin is not needed
* A network of membranes and vesicles.
,* The Golgi apparatus packages proteins into vesicles
* The vesicles break off from the Golgi complex and migrate to a variety
of intracellular and extracellular destinations.
* The Golgi complex is more prominent in some cells, particularly those
that secrete proteins. (ex. immunoglobulins)
Golgi complex = packaging center/transport facility Ans✓✓✓ Golgi
complex
• ______ occur with "passive" electrical activity (movement of sodium
(Na+), potassium (K+), chloride (Cl‐ ) across the plasma membrane).
• ________ result in small, transient changes in membrane potential.
• _______vary in terms of their strength and duration, and the signal
will not travel very far (the graded potential degrades over time and
space). Later (Weeks 5 and 6) we will contrast this with action
potentials.
• Action potential represent greater changes in the electrical p Ans✓✓✓
Graded potentials
• A measure of the osmotic pressure gradient determined by the water
potential between two solutions.
• The two solutions are separated by a semipermeable membrane.
• Determines the direction of diffusion.
, • The solutes that can't cross the membrane influence the tonicity. The
solutes that can freely cross the membrane don't influence tonicity
because they will equilibrate to have equal concentrations on either
side of the membrane. Ans✓✓✓ Tonicity
• Actin filaments (i.e., microfilaments) - components of the contractile
apparatus
• Intermediate filaments (e.g., keratin filaments, neurofilaments)
• Microtubules - important for intracellular transport, support the
movement of chromosomes during mitosis, and allow the movement of
cilia and flagella. Ans✓✓✓ Cytoskeleton
• An ion‐transporting enzyme in the plasma membrane.
• This solute pump is important for sodium (Na+) and potassium (K+)
movement (active transport).
• Both ions are moving against their concentration gradients (i.e.,
Na+moving out of the cell and K+moving into the cell), which requires
energy. Ans✓✓✓ Na+‐K+‐ATPase pump
