Resting Membrane Potential

Question 1

What components make up the neuronal cell membrane?

Answer 1

Made up of a lipid bilayer, proteins, and some carbs

Question 2

Is the head of the phospholipid hydrophobic or hydrophilic?

Answer 2

Hydrophilic

Question 3

Is the tail of the phospholipid hydrophobic or hydrophilic?

Answer 3

Hydrophobic

Question 4

The cell membrane is ______________

Answer 4

The Gatekeeper; slightly permeable

Question 5

The main purpose of cell membrane is to

Answer 5

separate ICF from ECF

Question 6

What are Glycolipids made of

Answer 6

Part sugar and part fat

Question 7

What are glycoproteins made of

Answer 7

Part sugar and part protein

Question 8

Cells are surrounded by

Answer 8

Extracellular fluid (ECF)

Question 9

Cell membrane allows cells to: (2)

Answer 9

1. Obtain from ECF what it needs at the right time
2. Keep out what it does not need

Question 10

What molecules pass easy?

Answer 10

Permeable to nonpolar + uncharged= hydrophobic substances EX: Lipids, O2, CO2

Question 11

What molecules need help to pass?

Answer 11

Impermeable to Polar + Ionic = Hydrophilic; Water

Question 12

Types of Transport (2)

Answer 12

Passive Transport (Diffusion) and Active Transport (ATPase)

Question 13

What is diffusion?

Answer 13

No cellular energy (ATP) is required; the substance moves with the concentration gradient

Question 14

With Concentration Gradient Movement

Answer 14

High-To-Low

Question 15

What is Active Transport?

Answer 15

ATP required; Move against the concentration gradient

Question 16

Against the concentration gradient

Answer 16

Low-To-High

Question 17

Two types of diffusions

Answer 17

Simple diffusion and (Passive) facilitated diffusion

Question 18

Diffusion continues until what is reached?

Answer 18

Equilibrium

Question 19

Equilibrium

Answer 19

The point when solute is equally distributed between two regions

Question 20

Rate depends on (2)

Answer 20

1. Size of the concentration gradient
2. Molecular weight of moving particles

Question 21

Simple diffusion

Answer 21

Only H2O and hydrophobic (nonpolar) substances; freely diffuse; and do not need helper proteins

Question 22

Passive Transport: Facilitated Diffusion

Answer 22

Diffuse through channel proteins; Specific; certain hydrophilic/polar molecules

Question 23

Two types of active transport

Answer 23

1. Primary Active Transport
2. Vesicular Transport

Question 24

Primary Active Transport

Answer 24

Requires solute pump (Na/K); AGAINST concentration/electrical gradient; REQUIRES ATP

Question 25

Are there more K+ or Na+ channels in cell membrane

Answer 25

K+

Question 26

______ Na+ (In or Out) and ______ K+ (In or Out)

Answer 26

3 Na+ out; 2 K+ in

Question 26

Vesicular Transport

Answer 26

Vesicles bud off Golgi with material that needs to leave the cell; Moves to cell membrane and fuses with it

Question 27

Exocytosis

Answer 27

Expels contents to outside ECF

Question 28

K+ ICF and ECF concentrations

Answer 28

150mM ICF 5mM ECF K+ flows out; hella leak channels

Question 29

Na+ ICF and ECF concentrations

Answer 29

10mM ICF 145mM ECF Na+ flows in; Some channels

Question 30

Ca2+ ICF and ECF concentrations

Answer 30

<1mM ICF 5mM ECF Ca2+ flows in; very small # of leak channels

Question 31

Cl- ICF and ECF concentrations

Answer 31

5mM ICF 100mM ECF Cl- flows in; small # of leak channels

Question 32

There are many types of ________ proteins ______ the cell

Answer 32

Negative; Inside

Question 33

Why does the Na+/K+ pump require ATP to work?

Answer 33

It moves against the gradient (K+ in; Na+ out)

Question 34

Resting K+ channels are

Answer 34

always open

Question 35

Voltage-gated channels

Answer 35

Open at certain voltage levels; in response to change in the membrane potential

Question 36

Ligand-gated channels

Answer 36

Extracellular Lock & Key

Question 37

Signal-gated channels

Answer 37

Intracellular Lock & Key

Question 38

RMP (Resting Membrane Potential) value

Answer 38

-70mV

Question 39

How to measure membrane potential

Answer 39

Microelectrode goes inside axon

Question 40

Cells are more ______ inside than outside

Answer 40

Negative

Question 41

Nernst Equation

Answer 41

E=RT/zF Log (ions out/ions in)

Question 42

What does the Nernst Equation calculate

Answer 42

Calculates equilibrium potential for single ion crossing membrane

Question 43

Goldman-Hodgkin Katz Equation

Answer 43

Em=61/z log(Pna[Na]out-Pk[K]out/Pna[Na]in-Pk[K]in)

Question 44

Changes in membrane potential

Answer 44

Way to receive, integrate, and send information

Question 45

Two types of Membrane potentials (2)

Answer 45

1. Graded potential 2. Action potential

Question 46

Graded potentials

Answer 46

SHORT distances; unless the threshold is reached, they will decay

Question 47

Action Potentials

Answer 47

LONG distances; threshold is reached

Question 48

Depolarize

Answer 48

More positive

Question 49

Hyperpolarized

Answer 49

More negative