Cell Membrane Transport

The chemical force for which of the following ions is directed into the cell?

Which of the following is found in greater concentration inside the cell than outside?

When molecules are passively transported across a membrane, the direction of their movement is dictated by the molecules tendency to move

Of the gradients listed below, which is the most accurate description of the force that ultimately determines the movement of ions across the membrane ?

Molecules tend to move spontaneously _______ their chemical gradient

When more then one ion species is present on both sides of the membrane, the chemical driving force acting on Na+ will include

Which of the following is a reflection of the unequal distribution of positive and negative ions across the plasma membrane?

Comparing intracellular to extracellular fluid, the intracellular fluid has a _____ charge relative to the outside of a cell due to the presence of more ______ in that solution.

The unequal distribution of charge in solutions on either side of a membrane will lead to a ______ of charge across the membrane and a ______ of counter ions in a region close to the membrane.

Which of the following factors does NOT directly affect the direction or magnitude of the electrical driving force?

Which of the following is NOT a determinant of the magnitude and direction of the equilibrium potential for an ion?

If a positively charged ion is more concentrated outside the cell, the forces required to balance the chemical gradient would be directed _______. Thus the equilibrium potential for this ion would be ______ charged.

Which of the following cells would have a greater electrical attraction for sodium ions to enter the cell?

If a negatively charged ion is more concentrated outside the cell, the forces required to balance the chemical gradient would be directed ______. Thus, the equilibrium potential for this ion would be ______ charged.

Which of the following can be used to determine an ion's equilibrium potential?

The potassium equilibrium potential is -94 mV. what does this means?

An anion has an equilibrium potential of -40mV. What direction are the chemical and electrical forces acting on the anion at the rating membrane potential (-70mV)?

Which of the following best describes the potassium equilibrium potential?

The equilibrium potential describes the membrane potential where what two forces are balanced?

Which of the following is NOT required to determine equilibrium potential of a particular ion?

Which of the following does NOT directly determine the rate at which an ion will move passively across a membrane?

Which of the following would NOT increase the rate of simple diffusion across the phospholipid bilayer of the plasma membrane?

Which of the following pairs of characteristics is more likely to make a substance diffuse through the cell membrane ?

Oxygen diffuses from blood into cells down its concentration gradient. As cells become more active and oxidative phosphorylation increases in the cell, which of the following occurs?

How will increases in the concentration difference of an uncharged molecule across a membrane affect the rate of diffusion between two compartments?

The concentration of sodium is greater in the extracellular fluid compared to the intracellular fluid. If the membrane potential was equal to the equilibrium potential for sodium, then what would be the direction of the electrochemical force acting on sodium?

One way that membrane surface area is increased is absorptive cells in through increasing the ________ of the apical membrane

When a substance crossing the membrane is driven by diffusion, the net flux of that molecule can be describes mathematically by_____-

Sodium permeability refers to a property of

Which of the following will NOT increase the net flux of an ion across a membrane?

Molecules with a relatively high lipid solubility are capable of crossing the membrane______

Which of the following is NOT true for all three of the following transport mechanisms: facilitated diffusion, primary active transport, and secondary active transport?

Which of the following transport mechanisms is passive?

A carrier is a transmembrane protein that moves molecules across the membrane through

In general, the molecules that move through specific carrier proteins are determined by which of the following?

In facilitated diffusion

Which of the following transport mechanisms requires energy?

In active transport, the affinity of the carrier protein for the molecule being transported is greater in which side of the membrane?

During cotransport of glucose with sodium , sodium increases the affinity of the carrier molecule for glucose when the binding site is facing which side?

What is the main difference between primary and secondary active transport?

What are aquaporins?

Movement of water through aquaporins occurs by what process?

Most water molecules that cross the plasma membrane do so by

What transport process couples the movement of an ions against its electrochemical gradient to another ion that is moving down its electrochemical gradient that was established using cellular energy (ATP)?

Primary active transporters are unique in their ability to couple the movement of ions directly to what?

In addition to functioning as a transporter, primary active transporters also function as ________ in order to make use of energy

The first step of the Na+/K+ pump's activity involves the binding of which of the following?

The hydrolysis of ATP on the Na+/K+ pump results in

Na+ is released from its binding site on the Na+/K+ pump as a result of

Which of the following statements about the Ca+ pump is FALSE?

In secondary active transport with sodium, which of the following is FALSE?

Which of the following correctly describes cotransport of Y with sodium ?

Which of the following statements about glucose cotransport with sodium is true?

Which of the following statements about primary active transport is FALSE?

Which of the following statements about the Na+/K+ pump is FALSE?

Sodium-linked glucose transport, where both Na+ and glucose are moving in the same direction, is an example of

The flow of water across a membrane down its concentration gradient is called

If there is a difference in osmolarity between a cell and its environment, water will move ______ its osmotic pressure gradient.

The osmotic pressure of a solution is an

The extent of ion movement through the _____ space between epithelial cells is determined by the extent of _____ coupling between neighboring epithelial cells

The movement of a number of molecules across the apical surface of the epithelial cell by secondary transporters is coupled to the ______- gradient that is maintained by the _____ on the basolateral surface of the epithelial cell

When solute is actively transported across epithelium, what usually follows?

Oxygen is able to move across the cell membrane based upon its thermal energy

The movement of a molecule is determined by its energy state, with that molecule moving from a lower to a higher energy state.

In the presence of two or more ions, it is the sum of their concentration that determines the direction of movement of those ions across a membrane.

Most of the time, the body is neutral with respect to its electrical charge due to the equal distribution of anions and cations within the body.

If the membrane potential is equal to the equilibrium potential for an ion, individual ions will not move across membrane in either direction.

Ions move passively down their electrochemical gradient

The rate at which molecules are actively transported across a membrane is determined by the rate of transport of individual pumps and the number of pumps in the membrane.

If the direction of the net flux of an ion is against its electrochemical gradient, then that transport is passive.

The driving force for simple diffusion is the electrochemical gradient.

In facilitated diffusion, the carrier protein has equal affinity for the molecule being transported on both sides of the membrane

Ions can always move through the ion channels present in the plasma membrane as long as there is an electrochemical gradient to drive the movement

Primary active transporters are similar to carriers, with the exception that they are able to use energy to move ions against their electrochemical gradient

Pumps can move ions in either direction, as long as it is against that ions electrochemical gradient

A cotransporter uses an ions concentration gradient to move a second ion or molecule in the same directions the first.

The movement of water across a membrane is always a passive process

Large differences in water concentration are required to drive water across a membrane.

At the resting membrane potential, a cell is at equilibrium

At resting membrane potential, leakage of sodium ions into the cell and potassium ions out of the cell is balanced by the action of the Na+/K+ pump.

Osmosis occurs through aquaporins

Phagosomes are formed following receptor- mediated endocytosis

Aquaporins are primary active transporters of water