Module 3 - Membrane Dynamics

Question 1

Cations and anions are not distributed evenly throughout the body, creating a state of ? disequilibrium

Answer 1

Electrical disequilibrium

Question 2

Solutes in the body are in a state of ? disequilibrium

Answer 2

Chemical disequilibrium

Question 3

Water moves freely between membranes by way of

Answer 3

Osmosis

Question 4

This unit describes the number of solutes in a solution
*molecules per L

Answer 4

Osmolarity

Question 5

This variable does not have any units and describes the nature of a solution when a cell is placed in it

Answer 5

Tonicity

Question 6

Cells swell in these types of solutions

Answer 6

Hypotonic

Question 7

Cells shrink in these types of solutions

Answer 7

Hypertonic

Question 8

If the cell does not change in size, the solution is

Answer 8

Isotonic

Question 9

The concentration of these kinds of solutes in the cell determine tonicity

Answer 9

Non-penetrating solutes

Question 10

These kinds of solutes contribute to the osmolarity of a solution but not the tonicity

Answer 10

Penetrating solutes

Question 11

Movement of mass fluid that moves alongside other dissolved substances in response to a pressure gradient

Answer 11

Bulk flow

Question 12

(Lipophobic/Lipophilic) substances move across the cell membrane by diffusion

Answer 12

Lipophilic

Question 13

This transport does not require the input of energy

Answer 13

Passive transport

Question 14

This is the passive movement of molecules from an area of high concentration to one of lower concentration

Answer 14

Diffusion

Question 15

Diffusion does not stop until it reaches ?

Answer 15

Equilibrium

Question 16

Diffusion is directly related to ?

Answer 16

Temperature

Question 17

Diffusion is (slow/fast) across long distances

Answer 17

Slow

Question 18

Large macromolecules/particles are brought into the cell by

Answer 18

Endocytosis

Question 19

Material leaves the cell by

Answer 19

Exocytosis

Question 20

When vesicles that come into the cell by endocytosis are returned to the cell membrane, this is considered

Answer 20

Membrane recycling

Question 21

During this process, ligands will bind to membrane receptors that concentrate in pits before pinching off into the cell

Answer 21

Receptor-mediated endocytosis

Question 22

During this process, the vesicle membrane fuses with the host-cell membrane before releasing contents to extracellular space

Answer 22

Exocytosis

Question 23

Exocytosis requires

Answer 23

ATP

Question 24

These proteins form water-filled channels on the cell membrane that link the intracellular and extracellular compartments

Answer 24

Channel proteins

Question 25

These proteins regulate movement across a cell membrane by opening and closing

Answer 25

Gated channels

Question 26

Protein-mediated diffusion is AKA

Answer 26

Facilitated diffusion

Question 27

This transport pushes substances against their concentration gradient and requires an external source of energy

Answer 27

Active transport

Question 28

In this kind of active transport, the external energy comes directly from ATP

Answer 28

Primary active transport

Question 29

In this kind of active transport, external energy comes from the kinetic energy built up by the concentration gradient and indirectly by ATP

Answer 29

Secondary active transport

Question 30

This is the most important active transporter

Answer 30

Sodium-Potassium pump

(Na+/K+ -ATPase)

Question 31

The sodium-potassium pump does what?

Answer 31

Pumps sodium out of the cell and potassium into the cell

Question 32

All carrier-mediated transport demonstrates these 3 things:

Answer 32

Specificity, saturation, and competition

Question 33

Related molecules may compete for a single transporter

Answer 33

Competition

Question 34

This describes when the membrane transporters are working at their maximum rate

Answer 34

Saturation

Question 35

The ability of a transporter to move only one molecule/one group of molecules at a time

Answer 35

Specificity

Question 36

The body is electrically (+, -, neutral)

Answer 36

Neutral

Question 37

The inside of the cells are more (+, -) compared to the outside of cells

Answer 37

More negative

Question 38

The electrical gradient between ECF and ICF is known as the

Answer 38

Resting membrane potential difference

Question 39

The movement of an ion across a membrane is influenced by the ? for that ion

Answer 39

Electrical gradient

Question 40

The equilibrium potential of any ion can be calculated by using this equation

Answer 40

Nernst equation

Question 41

In most living cells, which ion normally determines resting membrane potential?

Answer 41

K+