7-1 (8.12.16)

Question 1

most of the time a cell’s membrane potential is (+/-)

Answer 1

negative

Question 2

things that influence whether an ion will flow thru membrane

Answer 2

1) [ ] gradient
2) electrical gradient
3) permeability of membrane for ion

Question 3

define inward current

Answer 3

flow of positive charge INTO cell

Question 4

define Nernest equilibrium

Answer 4

voltage gradient exactly compensates the concentration gradient, so NO NET flux

Question 5

purpose of Nernest eq

what other thing does the same thing

Answer 5

predict if ion will have net flux in or out of cell at a given membrane potential

net driving force (Vm - Eion)

Question 6

define the eq components of net driving force

Answer 6

Vm is membrane potential

Eion is Nernst potential

Question 7

resting membrane potential is near E_?

Answer 7

k

near potassium’s

Question 8

define reversal potential

Answer 8

when there’s no net ionic flux thru channel

Question 9

purpose of knowing reversal potential

Answer 9

predict whether opening/closing of ion channel will depolarize or hyperpolarize membrane

Question 10

GHK eq - how it’s gonna be tested

Answer 10

know that it calculates Vm (membrane potential)

know that you plug in permeability and [ ] gradient

eq predicts reversal potentials

Question 11

define epithelium

Answer 11

cellular covering of internal and external surfaces of body,

Question 12

features of epithelial tissue

• arranged in what
• rests on what
• derived from what
• vascular or avascular

Answer 12

• arranged in sheets
• rests on basal lamina
• derived from all three germ layers
• avascular

Question 13

cells exhibit “” (polarity)

what does this mean

Answer 13

sidedness

all surfaces are NOT equal

Question 14

dif bt apical and lateral and basal surface

Answer 14

apical interacts with lumen (read: refers to TOP, like apex)

lateral HAS intercellular junctions (read: refers to internal stuff)

basal interacts with underlying connective tissue (refers to bottom)

Question 15

stereo cilia is most closely related to what

Answer 15

micro villi

Question 16

what composes the basement membrane

Answer 16

basal lamina

reticular lamina

Question 17

basal infoldings are typical in areas requiring () transport

Answer 17

active

Question 18

necessary fact about pseudostratified columnar

Answer 18

all contact basal lamina but not all reach luminal surface

Question 19

dif bt exocrine and endocrine

Answer 19

exo = duct on surface and secrete apically

endo = no ducts and secrete hormone basally

Question 20

name the two types of exocrine glands

Answer 20

goblet

tubular