BIOL252 PhysioEx 1: Ex 1 Cell Transport Mechanisms & Permeability

Does active or passive transport require the cell to provide energy in the form of ATP?

Active Transport

The movement of particles from an area of greater concentration to an area of lesser concentration is

a. diffusion

b. osmosis

c. active transport

d. kinetic energy

*a. diffusion

b. osmosis (water across semipermeable membrane)

c. active transport (usually against gradient)

d. kinetic energy (energy of motion)

All of the following are true of active transport except

a. ATP is used to power active transport

b. Solutes are moving with their concentration gradient

c. It uses a membrane-bound carrier protein

d. It can only occur in certain animals

a. ATP is used to power active transport

*b. Solutes are moving with their concentration gradient

c. It uses a membrane-bound carrier protein

*d. It can only occur in certain animals

In simple diffusion, dialysis tubing mimics the cell's

a. nucleus

b. plasma membrane

a. nucleus

*b. plasma membrane

selectively permeable

the characteristic of a substance to all certain amounts of particular items through that substance

passive transport

driven by gradient differences

active transport

cell requires energy in form of ATP

uses membrane-bound carrier protein

solutes move against their gradients

simple diffusion

passive transport requiring no assistance

facilitated diffusion

passive transport requiring membrane-bound carrier protein

kinetic energy & diffusion

solutes disperse evenly due to molecular motion

osmosis

movement of water across a membrane

filtration

passive transport driven by pressure gradient

bodily filtration occurs in

across capillary walls

vesicular transport

phagocytosis, endocytosis, pinocytosis, exocytosis

Driving force for diffusion is

a. ATP

b. Kinetic energy of molecules

c. Membrane transport protein

d. Dialysis membrane

a. ATP

*b. Kinetic energy of molecules

c. Membrane transport protein

d. Dialysis membrane

In diffusion, molecules move

a. from high to low concentration

b. from low to high concentration

c. from either high or low concentration

d. against concentration gradient

*a. from high to low concentration

b. from low to high concentration

c. from either high or low concentration

d. against concentration gradient

Which of the following membrane has the largest pore size?

a. 20 MWCO

b. 50 MWCO

c. 100 MWCO

d. 200 MWCO

a. 20 MWCO

b. 50 MWCO

c. 100 MWCO

*d. 200 MWCO

MWCO

Molecular Weight Cut Off

Avogadro's Number is a constant for the number of

a. moles

b. molecules

c. milliliters

d. atoms

a. moles

*b. molecules

c. milliliters

d. atoms

The effect on the diffusion rate of increasing the concentration of NaCl from 9 mM to 18 mM in the left beaker was to

a. decrease

b. increase

c. no change

a. decrease

*b. increase

c. no change

Urea diffused [Faster | Slower] because it is [Larger | Smaller] than Na⁺.

Slower, Larger

Diffusion rate & particle size

inversely proportional

Which of the following solutes did not pass through the 200 MWCO membrane?

a. glucose

b. albumin

c. urea

d. neither glucose nor albumin

a. glucose

*b. albumin

c. urea

d. neither glucose nor albumin

When diffusion stops, the solution has reached

a. equilibrium

b. saturation

c. concentration

d. maturation

*a. equilibrium

b. saturation (when solution can hold no more solutes)

c. concentration

d. maturation

Molecules need a carrier protein to help them move across a membrane because

a. not lipid soluble

b. are lipid soluble

c. too large

d. either lipid insoluble or too large

a. not lipid soluble

b. are lipid soluble

c. too large

*d. either lipid insoluble or too large

In facilitated diffusion movement is [Active | Passive] and [Down | Against] a concentration gradient.

Passive, Down

Examples of molecules that might require facilitated diffusion are

a. glucose

b. sodium

c. potassium

d. all of the above

a. glucose

b. sodium

c. potassium

*d. all of the above

Which does not affect the rate of facilitated diffusion?

a. amount of intracellular ATP

b. concentration of solutes

c. number of membrane carriers

d. gradient steepness

*a. amount of intracellular ATP

b. concentration of solutes

c. number of membrane carriers

d. gradient steepness

Which increase the rate of facilitated diffusion for glucose?

a. increasing its concentration

b. increasing number of membrane carriers

c. adding sodium chloride

d. both a and b

a. increasing its concentration

b. increasing number of membrane carriers

c. adding sodium chloride

*d. both a and b

For facilitated diffusion, increase the concentration of glucose on one side of the membrane is the same as

a. flattening its gradient

b. steepening its gradient

c. adding ATP

d. changing the direction of diffusion

a. flattening its gradient

*b. steepening its gradient

c. adding ATP

d. changing the direction of diffusion

When all membrane carriers are engaged, they are

a. saturated

b. satiated

c. inhibited

d. selected

*a. saturated

b. satiated

c. inhibited

d. selected

Na⁺Cl⁻ had no effect on glucose transport because

a. glucose & sodium are cotransported

b. sodium is not required for glucose transport in the simulation

c. sodium is actively transported in the simulation

d. membrane proteins were saturated

a. glucose & sodium are cotransported

*b. sodium is not required for glucose transport in the simulation

c. sodium is actively transported in the simulation

d. membrane proteins were saturated

Which of the following is true of osmosis?

a. requires energy

b. movement is against water's concentration gradient

c. it is a type of diffusion

d. it refers to the movement of solutes

a. requires energy

b. movement is against water's concentration gradient

*c. it is a type of diffusion

d. it refers to the movement of solutes

Which of the following when a cell is placed in a hypertonic solution?

a. water enters the cell

b. cell swells

c. cells burst

d. cells shrink

a. water enters the cell

b. cell swells

c. cells burst

*d. cells shrink

First three describe a series of events if the cell is placed in a hypotonic solutions

The variable affecting osmotic pressure is

a. concentration of nondiffusing solutes

b. concentration of diffusing solutes

c. rate of diffusion

d. pore size of membrane proteins

*a. concentration of nondiffusing solutes

b. concentration of diffusing solutes (these will diffuse as water is diffusion)

c. rate of diffusion

d. pore size of membrane proteins (water doesn't need membrane proteins)

Net movement of water into a cell occurs when the cell is in a ____________ solution.

a. hypertonic

b. hypotonic

c. isotonic

d. hypnotonic

a. hypertonic (water wants out of cell)

*b. hypotonic

c. isotonic (equilibrium)

d. hypnotonic (not a word)

If you double the concentration of a nondiffusible solute that is on one side of a membrane, the osmotic pressure will

a. be unchanged

b. be cut in half

c. double

d. go to zero

a. be unchanged

b. be cut in half

*c. double

d. go to zero

Which membrane disallows passage of Na⁺Cl⁻?

a. 20 MWCO

b. 50 MWCO

c. 100 MWCO

d. 200 MWCO

*a. 20 MWCO

b. 50 MWCO

c. 100 MWCO

d. 200 MWCO

(mol weight NaCl ~58, disassociated ions also too large: Na+~23 Cl-~35)

When a solute is able to diffuse through a membrane

a. changes in volume occur

b. equilibrium is reached

c. there is net movement of water

d. pressure changes occur

a. changes in volume occur

b. equilibrium is reached

c. there is net movement of water

d. pressure changes occur

Water diffuses

a. against its concentration gradient

b. away from solutes

c. toward solutes

d. utilizing ATP

a. against its concentration gradient (impossible without using energy, diffusion is passive)

b. away from solutes (no, water wants to go where there is less water)

*c. toward solutes

d. utilizing ATP (nope, that's active transport)

Filtration is a process that

a. is active

b. requires ATP

c. is passive

d. is active & requires ATP

a. is active

b. requires ATP

*c. is passive

d. is active & requires ATP

Filtration is dependent on

a. concentration gradient

b. hydrostatic pressure gradient

c. kinetic energy gradient

d. osmotic pressure gradient

a. concentration gradient

*b. hydrostatic pressure gradient

c. kinetic energy gradient

d. osmotic pressure gradient

Filtrate

a. includes fluids

b. includes solutes

c. passes through the filter

d. all

a. includes fluids

b. includes solutes

c. passes through the filter

*d. all

An important site of human bodily filtration is

a. skin

b. muscles

c. ovaries

d. kidneys

a. skin

b. muscles

c. ovaries

*d. kidneys

After filtration, substances that pass through the filter are called the filtrate, which includes

a. solvent

b. solutes

c. water

d. all

a. solvent

b. solutes

c. water

*d. all

The top beaker in the simulation corresponds to the

a. blood capillary

b. blood capillary wall

c. interstitial space

d. kidney tubule

*a. blood capillary

b. blood capillary wall

c. interstitial space

d. kidney tubule

Why was there not 100% recover of Na⁺Cl⁻ with any of the membranes?

a. The solute was too large to fit through the pores

b. A longer filtration time was needed

c. Some of the solute remained on the membrane filter

d. A chemical reaction occurred

a. The solute was too large to fit through the pores

b. A longer filtration time was needed

*c. Some of the solute remained on the membrane filter

d. A chemical reaction occurred

An increase in blood pressure would probably _________ filtration in the kidneys.

a. decrease the rate of

b. increase the rate of

c. stop

d. block

a. decrease the rate of

*b. increase the rate of

c. stop

d. block

The movement of sodium & potassium maintained by the Na⁺-K⁻ pump

a. is against a concentration gradient

b. is with a concentration gradient

c. requires diffusion

d. requires energy and is against a concentration gradient

a. is against a concentration gradient

b. is with a concentration gradient

c. requires diffusion

*d. requires energy and is against a concentration gradient

The sodium-potassium pump is classified as a(n)

a. antiporter

b. symporter

c. uniporter

d. isoporter

*a. antiporter

b. symporter (No, Na & K going in opposite directions)

c. uniporter (single substance only)

d. isoporter

coupled transport

active transport that moves >1 substance

symporter

solutes move in same direction

antiporter

solutes move in opposite directions

uniporter

active transport that moves a single substance

The sodium-potassium pump moves ____ Na⁺ and _____ K⁻ simultaneously

a. 2, 3

b. 3, 2

c. 3, 3

d. 2, 2

a. 2, 3

*b. 3, 2

c. 3, 3

d. 2, 2

Solutes that require active transport for movement might be too large to pass or might be

a. lipid insoluble

b. lipid soluble

c. too small to pass

d. able to move with concentration gradient

*a. lipid insoluble

b. lipid soluble

c. too small to pass

d. able to move with concentration gradient

Regarding the sodium-potassium pump, if ATP is increased while the concentrations of sodium and potassium are unchanged, then

a. the ions were transported more quickly

b. more ions were transported

c. ions were transported more slowly

d. fewer ions were transported

a. the ions were transported more quickly

*b. more ions were transported

c. ions were transported more slowly

d. fewer ions were transported