CH. 11: Wrap Up Assignment COMPLETE Flashcards
A cell exports H + from the cytosol to the extracellular space. What does this do to cytosolic pH?
either increases or decreases pH, depending on the electrochemical gradient for protons
increases pH
decreases pH
none of the above
increases pH
This transporter mediates movement of glucose from the lumen of the small intestine into epithelial cells. What should a beverage contain to mediate optimal glucose uptake?
glucose
sodium
both
both
In a bacterium that relies on a proton gradient to drive uptake or export of solutes, in which direction is this pump likely to run when ATP levels are sufficient?
toward proton uptake into the bacterium
toward proton export from the cytosol across the plasma membrane
into the bacterium when there’s ATP in the extracellular environment
into the bacterium when pH is low
toward proton export from the cytosol across the plasma membrane
A cell exchanges Cl- for HCO3- with HCO3- entering the cytosol. What does this do to cytosolic pH?
no change, because the transport is electrically neutral
increases
decreases
increases
The sarcoplasmic/endoplasmic reticulum ATPase pumps Ca2+ into ___________, and its ATP binding domain is in ___________.
the lumen of the SR; the lumen of the SR
the lumen of the SR; the cytosol
the cytosol; the cytosol
the cytosol; the lumen of the SR
the lumen of the SR; the cytosol
For a typical mammalian cell, the concentration of Ca2+:
is higher in the extracellular fluid than the cytosol
is the same in the cytosol and the extracellular fluid
is greater in the cytosol than in the lumen of the endoplasmic reticulum
is higher in the cytosol than the extracellular fluid
is greater in the cytosol than in the lumen of the sarcoplasmic reticulum
is higher in the extracellular fluid than the cytosol
The permeability coefficient in regard to ability of a solute to diffuse across a lipid bilyar is determined in part by the solute’s ability to:
interact with polar head groups
flip-flop across
dissolve in an aqueous environment
partition into a hydrophobic environment
partition into a hydrophobic environment
Based only on the properties of helices (disregard potential roles of side chains), a chloride ion would be likely to be attracted to:
the N-terminus of this helix
the C-terminus of this helix
the N-terminus of this helix
All are true of myelination EXCEPT:
restricts Na+/K+ ATPases to only the nodes of an axon
increases transmission speed of action potentials
results from wrapping of a glial cell plasma membrane around an axon
causes transmembrane ion exchange across the entire area of the plasma membrane in the axon
causes transmembrane ion exchange across the entire area of the plasma membrane in the axon
The bonds between the asparagine side chains and water shown here are
covalent bonds
hydrogen bonds
ionic attraction
hydrophobic interactions
hydrogen bonds
The shortest time between two action potentials is determined by:
inactivation and the refractory period for voltage-gated Na+ channels
opening of voltage-gated K+ channels
inactivation and the refractory period for voltage-gated K+ channels
opening of voltage-gated Na+ channels
action of the Na+/K+ ATPase
inactivation and the refractory period for voltage-gated Na+ channels
Opening of which of these would either cause inhibitory postsynaptic potentials or counteract a depolarizing influence given the typical ion distributions of a mammalian cell?
Note: to meet these criteria, as long as the channel opening does at least one or another, it fits what’s being asked for.
Na + channels
Ca 2+ channels
K + channels
Cl - channels
all of the above
B, C, and D
C and D
C and D
In an alpha-motorneuron, which is depolarizing?
opening of voltage-gated Ca2+ channels
opening of voltage-gated Na+ channels
both of the above
both of the above
