Physiology Topic 6.1 Quiz—Transport Part 1
In Figure 6.6, which line includes active transport?
A
In Figure 6.6, which line represents diffusion of Cl- from C1 to C2 through a channel if there is a constant negative voltage applied on C1?
A
A cation and an anion will ________ each other.
Attract
A hormone binds to a receptor in the nucleus and affects transcription. In Figure 6.2, which line best describes the transport of this hormone across the cell membrane?
B
In Figure 6.1, which of the following represents facilitated diffusion?
B
In Figure 6.2, which of the following represents channel diffusion?
B
In Figure 6.2, which of the following represents facilitated diffusion?
B
In Figure 6.2, which of the following represents simple diffusion?
B
In Figure 6.4, which represents translocation of GLUT transporters into to membrane if the molecule being transported is glucose?
B to D
Which of the following will NOT increase the net flux of an ion across a membrane? A. increased concentration gradient across the membrane B. reduced surface area C. more channels for that ion in the membrane D. elevated permeability of the membrane E. All options
B. reduced surface area
A hormone binds to a receptor in the nucleus and affects transcription. In Figure 6.1, which line best describes the transport of this hormone across the cell membrane?
C
In Figure 6.1, which of the following represents channel diffusion?
C
In Figure 6.1, which of the following represents how steroid hormones would move through a membrane?
C
In Figure 6.1, which of the following represents simple diffusion?
C
Which property of diffusion best helps explain the necessity of the circulatory system in large multicellular organisms? A. Diffusion rate is inversely proportional to molecule size B. Diffusion can take place across a partition that separates two systems C. Diffusion is rapid over short distances but much slower over long distances D. Diffusion occurs faster with a larger concentration gradient E. Molecules move from an area of higher concentration to an area of lower concentration
C. Diffusion is rapid over short distances but much slower over long distances
The outside of a resting cell is positive relative to the inside. This is an example of...
Chemical disequilibrium
In Figure 6.3, which of the following best represents a knockdown in the number of channels?
D
The cell membrane can better store charge if... A. the lipid bilayer becomes a better insulator B. the ECF and cytoplasm are better conductors C. the membrane is thinner D. All options
D. All options
Which of the following would NOT decrease the rate of diffusion across a cell membrane? A. a decrease in the concentration gradient B. a decrease in membrane permeability C. a decrease in the surface area of the membrane D. a decrease in molecular weight of the solute
D. a decrease in molecular weight of the solute
Which of the following molecules can move across the phospholipid bilayer by simple diffusion? A. Water B. Steroids C. Lipids D. Lipids and water only E. all of the options
E. all of the options
Which of the following events do NOT regulate channel gating? A. small molecule binding B. physical tension C. membrane potential D. phosphorylation/dephosphorylation E. all options are known to regulate channel gating
E. all options are known to regulate channel gating
A phospholipid bylayer acts as a good...
Electrical insulator
Which body fluid compartment typically contains high Na+ and Cl-?
Extracellular fluid only
When a substance crossing the membrane is by simple or channel diffusion, the net flux of that molecule can be described mathematically by...
Fick's law
One way that membrane surface area is increased in absorptive cells is through increasing the ________ of the _______ membrane.
Folding; apical
Which body fluid compartment typically contains high concentrations of K+ and immpermeable large anions (e.g., proteins)?
Intracellular fluid only
Which is true for the Fick equation?
J = net flux (e.g., molecules crossing a membrane per unit time)
Passive transport refers to a process that requires
No input of energy
When a solute crossing the membrane through a transporter, the net flux of that molecule can be described mathematically by...
Saturation kinetics
In general, the molecules that move through specific transporters are determined by which of the following?
The unique fit to binding sites on the protein
In Figure 6.5, what will be true at equilibrium if only Na+ is permeable?
[Na+] will be higher on the left and the right will be positive
Facilitated diffusion and active transport differ in that active transport moves a solute _________ from equilibrium, facilitated diffusion moves a solute ____________ equilibrium
away; toward
Which ion(s) have a net electrical force acting to move the ion(s) out of the cell? (Assume a resting membrane potential (Vm) of -70mV.)
both A- and B- ions
Which ion(s) have a net chemical force acting to move the ion(s) into the cell? (Assume a resting membrane potential (Vm) of -70mV.)
both X+ and B- ions
At equilibrium unidirectional diffusion occurs in both directions at __________ rates
equal
All of the following are types of transport. Identify ALL that occur via proteins.
facilitated diffusion, primary & secondary active transport
In facilitated diffusion, a molecule is moved down its concentration gradient with the assistance of a _____________ ______________ molecule, and no ______ is required
protein carrier; ATP
Anions will ________ each other.
repel
When a transporter becomes ______________, transporters have reached a maximal net flux, beyond which further increases in solute concentration no longer affect net flux
saturated
Gated channels for sodium ions may include...
chemical, mechanical, & voltage gates
Fick's law of diffusion states that the rate of diffusion across a membrane is proportional to _________________ gradient, _____________ ________, and membrane __________________
concentration; surface area; permeability
