Block 2

Question 1

Most brain function can be explained by the influence that the movement of these 3 salt atoms (ions) across the neuronal membrane have on the electrical charge of a neuron

Answer 1

potassium, sodium, chloride

Question 2

All matter is formed of __

Answer 2

atoms

Question 3

Atoms bond together into aggregates called __

Answer 3

molecules

Question 4

Atoms that have either lost or gained a charge

Answer 4

ions

Question 5

Positively charged ions

Answer 5

cations

Question 6

Negatively charged ions

Answer 6

anions

Question 7

A negatively charged surface attracts __ ions

Answer 7

positive

Question 8

A positively charged surface attracts __ ions

Answer 8

negative

Question 9

one mole of particles in one liter of solution

Answer 9

one molar solution

Question 10

μM (micromole)

Answer 10

one millionth of a mole

Question 11

mM (millimole)

Answer 11

one thousandth of a mole

Question 12

nM (nanomole)

Answer 12

one billionth of a mole

Question 13

intracellular environment is rich in what ion?

Answer 13

potassium

Question 14

extracellular environment is rich in what ion?

Answer 14

sodium

Question 15

adaptation occurred and first existing neurons placed leaky, porous proteins in the membrane called ___ so that ions could enter and exit

Answer 15

ion pores

Question 16

proteins anchored in the membrane that form a channel from inside to outside

Answer 16

ion pores

Question 17

monomer ion pore

Answer 17

only have one protein

Question 18

polymer ion pore

Answer 18

many proteins linked together

Question 19

each of the ion pores have ___ trans-membrane regions and __ intracellular and extracelular regions

Answer 19

hydrophobic ; hydrophilic

Question 20

What happens when potassium channels are open? Why does this happen?

Answer 20

potassium will move across the membrane and down its electro-chemical gradient following the Laws of Thermodynamics

Question 21

Describes the process of disorder in a system; evens out highly organized concentration gradients; ex diffusion: movement of ions from areas of high concentration (organized) to areas of low concentration (disorganized)

Answer 21

entropy

Question 22

Pushes K+ out of the cell and down the concentration gradient; depends on the difference between extracellular and intracellular concentrations (greater the difference = greater the push)

Answer 22

entropy

Question 23

principles of opposites attracting; electrostatic force: developing negative charge in a cell will stop the flow of positively charged potassium from leaving the cell

Answer 23

enthalpy

Question 24

the point where enthalpy (electrostatic force) balances out entropy (diffusion force) for any charged ion

Answer 24

equilibrium

Question 25

the difference in ___ across the cell membrane gives the cell its charge (an electrical value)

Answer 25

ion concentration

Question 26

the electrical charge necessary to balance out the process of diffusion; can be calculated by the nernst equation

Answer 26

equilibrium potential

Question 27

equilibrium potential for potassium; K+ will always try to make the cell this value

Answer 27

-93MV

Question 28

actual charge inside the cell

Answer 28

membrane potential

Question 29

resting potential of cell

Answer 29

-70mV

Question 30

upward deflection; gaining of positive charge in the neuron; charge goes towards 0

Answer 30

depolarization

Question 31

downward deflection; gaining of negative charge in the neuron; charge goes away from 0

Answer 31

hyperpolarization

Question 32

Which ions influence the vM of a neuron?

Answer 32

sodium, chloride, potassium

Question 33

equilibrium potential for sodium

Answer 33

+56 mV

Question 34

equilibrium potential for chloride

Answer 34

-66mV

Question 35

The equilibrium potentials for chloride and sodium have a __ influence on the vM

Answer 35

depolarizing

Question 36

__ of each ion plays a role in the vM

Answer 36

permeability (leakiness)

Question 37

Relative Permeabilities (most permeable to least permeable)

Answer 37

K : Cl : Na

Question 38

Resting Potential of the cell should be closer to __ and __ than __

Answer 38

Potassium, Chloride, Sodium

Question 39

determines the vM by considering the concentration of ions and permeability of ions across the membrane

Answer 39

Goldman equation

Question 40

Makes up for the 3mV unaccounted for by the Goldman equation

Answer 40

sodium/potassium pump

Question 41

Maintains the ion gradient, prevents continuous leaking

Answer 41

sodium/potassium pump

Question 42

Sodium/potassium pump moves __ sodium ions __ and __ potassium ions __

Answer 42

3 sodium ions out; 2 potassium ions in