Lyons Nsu-Phs4904 Membrane Transport Ch 6

Front 1

the pm is generally not permeable to _____, ____, ____, & _____.

Back 1

proteins, nucleic acids, large molecule, & structural molecules

Front 2

the pm is permeable to small ______, & ______

Back 2

small molecules, & lipid soluble substances

Front 3

the pm is selectively permeable to _____ & ______, which travel through the pm via channels

Back 3

ions, water

Front 4

transport across mb that does not require energy, nor a carrier, & travels down the concentration gradient:

Back 4

diffusion

Front 5

transport across pm from higher to lower conc., energetically favorable, includes carrier & non-carriers:

Back 5

passive transport

Front 6

when a substance is transported across pm down the concentration gradient, it moves from ____ to _____ concentration

Back 6

higher to lower

Front 7

what is active transport?

Back 7

lower to higher (up/against gradient), requires energy, & carrier protein

Front 8

diffusion of lipid soluble mo. thru pm, ions (sm. uncharged) thru ch. proteins, & water thru aquaporins are examples of _______ transport

Back 8

non-carrier mediated/ passive

Front 9

2 types of carrier mediated transport are ____, & _____

Back 9

facilitated diffusion, & active transport

Front 10

solute in a solvent is in random constant motion. this rate depends on ______

Back 10

heat (thermal heat energy)

Front 11

a solution consists of ____, & ____

Back 11

solvent, & solute molecules (book also says water)

Front 12

_____ in a solution is in random constant motion

Back 12

solute

Front 13

if a conc. diff, random motion of solute spreads out. this random motion is _____

Back 13

diffusion

Front 14

as a result of random molecular motion, most molecules move from higher to lower conc. until equal, this net movement is ______

Back 14

net diffusion

Front 15

waste molecules can be removed from the blood by having them diffuse through an ARTIFICIAL porous mb. this is called ______

Back 15

dialysis

Front 16

factors that contribute to the rate of diffusion are

Back 16

steepness of conc. gradient, 2-permeability of substance, 3-temp of solution, 4-mb surface area

Front 17

areas of body specialized for diffusion/absorption (i.e. GI tract) are often folded or contain microvilli. Why?

Back 17

to increase the surface area so molecules move more rapidly

Front 18

why do neurons use axons for diffusion?

Back 18

because distance is too long for diffusion

Front 19

5 lipid soluble molecules that can diffuse the pm are:

Back 19

O2, CO2, steroid hormones, alcohol, & some drugs (book also says ethanol & urea)

Front 20

steroid hormones have a ______nucleus

Back 20

cholesterol

Front 21

can water diffuse the pm?

Back 21

yes, if it is small, through aguaporin channels, osmosis

Front 22

large polar molecules require ____ to diffuse the pm

Back 22

carrier protein

Front 23

charged ions such as Na+ & K+ are impermeable. how do they get across the pm?

Back 23

via ion channels, either gated (pump), or non gated

Front 24

what 3 triggers can open gated ion channels?

Back 24

ligand binding, mechanical stretch, & mb voltage

Front 25

in the production of nerve & muscle impulses, specific ch's for ___ & ___ open & close in response to mb voltage

Back 25

Na+ & K+

Front 26

when your bladder is full it activates calcium to be released, which activates contraction. this is an example of:

Back 26

mechanical stretch

Front 27

what is osmosis?

Back 27

net diffusion of water (solvent) across a mb

Front 28

what is required for osmosis? (4)

Back 28

1-mb allows water mvmt, but not solute, 2-conc. gradient of solute (must be diff in conc), 3-higher to lower water conc, 4-aquaporins

Front 29

when solution is more dilute on 1 side of pm than the other, the more dilute solution has higher conc of ____, & lower conc of ____

Back 29

water molecules, solute

Front 30

when can osmosis occur?

Back 30

when water is more concentrated on one side than the other

Front 31

what is osmotic pressure?

Back 31

the pressure req. to stop osmosis

Front 32

because it is a measure of the force req. to stop osmosis, what does OSMP (osmotic pressure) indicate?

Back 32

how strongly a solution draws water by osmosis

Front 33

the greater the ______, the greater the OSMP

Back 33

solute concentration

Front 34

solutes that cant freely pass thru the mb can promote the osmotic mvmt of water & are said to be ____

Back 34

osmotically active

Front 35

what is excessive accumulation of fluid in the tissues called?

Back 35

edema

Front 36

what is liver cirrhosis?

Back 36

a damaged liver that is unable to produce sufficient amounts of albumin. can result in edema

Front 37

plasma proteins (such as albumin) cant freely pass from the capillaries to the tissue fluid, therefore they are considered to be ________

Back 37

osmotically active

Front 38

what is kwashiokor?

Back 38

protein malnutrition- (for children it ↓ IGF1 plasma protein, ↓ growth rate, & ↑ growth hormone. can result in giantism)

Front 39

_____ may result from abnormally low conc of plasma proteins, liver cirrhosis, or kwashiokor

Back 39

edema

Front 40

osmosis occurs when the water is (more? or less?) conc on one side than the other.

Back 40

more

Front 41

pure water has an OSMP of zero. A 360 g/L glucose solution has _____ the OSMP of 180g/L glucose solution

Back 41

twice

Front 42

what is molarity?

Back 42

way to define solute in a solution. 1 mole of solute in 1 L solution= 1 molar solution

Front 43

a way to define ratio of solute to water. 1 mole per kg (1 L) water= 1 molal

Back 43

molality

Front 44

when measuring molality, does the amount of water vary between solutions?

Back 44

no

Front 45

1 mole of NaCl= ___ Osm

Back 45

2

Front 46

if you take the solute: 1 mole of glucose (180g), & fill beaker up to 1 L mark with water, which will you have: 1 molar, or 1 molal?

Back 46

1 molar

Front 47

molarity X the # of dissociable ions, or the total molarity of a solution, is called ______

Back 47

osmolarity

Front 48

osmolarity depends on ______ & ______. the ratio of solute to solvent is very important

Back 48

osmotic pressure & solute molecules

Front 49

if you take solute: 1 mole of glucose (180g), & add 1 Kg (1 L) water, which will you have: 1 molar or 1 molal?

Back 49

1 molal

Front 50

1 mole of glucose Vs 1 mole of NaCl. which has more OSMP?

Back 50

NaCl

Front 51

what would happen if a rbc were placed in a hypotonic solution?

Back 51

lysis

Front 52

if a solution, has the same has the same osmolarity as plasma, it is _______ to plasma

Back 52

isosmotic

Front 53

plasma= ___ Osm, or ___ mOsm

Back 53

.3 Osm, or 300 mOsm

Front 54

______ & _____ are isosmotic to plasma

Back 54

5% dextrose & normal saline

Front 55

in an _____ solution, osmosis will not occur betw. solution & plasma

Back 55

isotonic

Front 56

a solution >300mOsm is ____-tonic

Back 56

hypertonic

Front 57

if an isosmotic glucose or saline solution is separated from plasma by a mb that is permeable to water but not glucose or NaCl, will osmosis occur?

Back 57

no, the solution is said to be isotonic

Front 58

what would happen if a rbc were dropped in a hypertonic solution?

Back 58

crenation

Front 59

what is tonicity?

Back 59

used to describe how a solution effects the osmotic movement of water

Front 60

a solution <300mOsm is ____-tonic

Back 60

hypotonic

Front 61

urea is iso-_____, but not iso- _____

Back 61

isosmotic, not isotonic

Front 62

Deltoid

Back 62

Origin: clavicle and scapula (acromion and adjacent scapular spine)
Insertion: deltoid tuberosity of humerus
Action: abducts shoulder, flexion and extension, medial and lateral rotation of humerus
Nerve: Axillary

Front 63

why do we say that urea is isosmotic?

Back 63

because it is freely permeable across mb

Front 64

what is Ringer's lactate?

Back 64

an isotonic solution

Front 65

what are the effects of mannitol?

Back 65

pulls water in (promotes osmosis),

Front 66

what would happen if urea were given intravenously?

Back 66

cell lysis would occur at .3M urea

Front 67

if a patient is dehydrated, it can _____their blood

Back 67

concentrate

Front 68

if a patient suffered brain trauma or stroke resulting in cerebral edema, what can they be given intravenously?

Back 68

mannitol- a hypertonic solution to reduce cell swelling

Front 69

_____ & _____ are too large for diffusion so they use a carrier to cross mb.

Back 69

glucose & amino acids

Front 70

what are 3 common characteristics of carrier proteins:

Back 70

specificity, saturation, & competition

Front 71

what does it mean when the carrier transport is saturated?

Back 71

as conc. of a transported molecule is ↑, its rate of transport will also ↑, but only up to a transport maximum. when max is reached, it is saturated

Front 72

carrier transport:
when will the rate of transport stop increasing?

Back 72

when the carrier transport reaches saturation

Front 73

what does it mean when glucose is found in a patients urine?

Back 73

glucose conc of blood & filtrate is too ↑ (hyperglycemia), so the transport max was exceeded. this usually results from inadequate secretion of insulin from diabetes mellitus, but can just be a result of a patient that recently ate a high carb meal

Front 74

which carrier proteins can bring glucose into the cell?

Back 74

GLUT glucose carriers only

Front 75

if 2 different aa (amino acids) were transported by the same carrier, would the rate of transport be (higher? or lower?) when they are present together than if they were alone.

Back 75

lower (competition)

Front 76

what does it mean when a carrier is specific?

Back 76

it can differentiate betw. substances. will only bind the molecule it is supposed to (i.e. GLUT carrier will bind glucose, but not fructose)

Front 77

what 2 things can allows cells to take up more glucose from the blood?

Back 77

exercise or insulin

Front 78

how do exercise & insulin help cells take up more glucose from the blood?

Back 78

they stimulate GLUT proteins to fuse with the mb which carry them through

Front 79

is the diffusion of glucose considered facilitated diffusion, or is it carrier mediated transport?

Back 79

both- same

Front 80

what is a binding site?

Back 80

site on a carrier protein that is made to fit a specific molecule for transport

Front 81

what type of transport requires pumps?

Back 81

active transport

Front 82

what can happen if a diabetic person overdosed their insulin?

Back 82

plasma glucose conc. abnormally ↓ (hypoglycemia), the rate of transport into brain cells may be too slow for metabolic needs, could result in loss of consciousness or death.

Front 83

what type of transport protein is referred to as a pump?

Back 83

primary active transport carrier

Front 84

when ATP breaks off its phosphate group, this energy can be used in what type of transport?

Back 84

primary active transport

Front 85

where are Ca+ pumps located?

Back 85

pm of all cells & mb of ER of striated muscle cells

Front 86

is Ca+ higher or lower inside the cell?

Back 86

lower

Front 87

name 3 primary active transport pumps:

Back 87

proton (H+), Ca+, & Na+K+

Front 88

what activates ATPase in the Ca+ pump?

Back 88

the binding of Ca+ to the binding site on the pump

Front 89

what does ATPase do in the Ca+ pump?

Back 89

hydrolyzes ATP breaking it into ADP & P (phosphate)

Front 90

what does ADP do in the Ca+ pump?

Back 90

makes a conformational change to the pump, which opens the passageway for Ca+ to move into the ECF

Front 91

what resets the Ca+ pump back to its original state so Ca+ in the cytoplasm can reach the binding site again?

Back 91

P (phosphate)

Front 92

a drastic change in cytoplasmic Ca+ could happen if ion channels were open & Ca+ rapidly rushed into the cell. this serves as a signal for _____ & _____

Back 92

nuerotransmitter release & muscle contraction

Front 93

where does striated muscle sequester (store) calcium?

Back 93

ER

Front 94

why is calcium in striated muscle important?

Back 94

for muscle contraction

Front 95

the Na+K+ pumps ____ out of the cell and ___ in the cell

Back 95

3 Na+ out & 2 K+ in

Front 96

is Na+ more conc. in the ECF or in the cytoplasm?

Back 96

Na+ is higher in the ECF

Front 97

there are 100's-1000's of these pumps in every cell:

Back 97

Na+K+ pumps

Front 98

the Na+K+ pump maintains ionic gradients essential for 3 functions:

Back 98

coupled transport (secondary active),
nerve & muscle stimulation, & osmotic balance

Front 99

the steep gradient of the Na+K+ pump provides energy for ______

Back 99

coupled transport (secondary active)

Front 100

what is secondary active transport?

Back 100

when energy to move against a gradient (uphill) is obtained by downhill transport of a substance (usually Na+)

Front 101

for the heart to pump to the aorta, it receives an electrochemical impulse from nerve & muscle cells. which pump is responsible for this impulse?

Back 101

Na+K+

Front 102

coupled transport is also known as _____

Back 102

secondary active transport

Front 103

is ATP required for secondary active transport?

Back 103

yes but indirectly

Front 104

what is cotransport?

Back 104

symport- when 2 molecules move in the same direction across a mb together

Front 105

which pump produces electrochemical impulses in nerve & muscle cells

Back 105

Na+K+

Front 106

give an example of cotransport/ symport:

Back 106

Na+ & glucose in kidney tubules. Na+ binding enhances glucose binding. they both travel across mb into the cell together

Front 107

what is countertransport?

Back 107

antiport- when 2 molecules move in opposite directions

Front 108

is the Na+K+ pump were to stop, what would happen?

Back 108

the increased Na+ within the cell would promote the osmotic inflow of water & the cells would damage/ swell

Front 109

give an example of countertransport:

Back 109

Na+/ Ca+ exchange. Na+ goes in and Ca+ goes out

Front 110

is secondary transport energetically favorable?

Back 110

yes

Front 111

what are 2 types of transport across epithelial mb?

Back 111

transcellular transport & paracellular transport

Front 112

what is transcellular transport?

Back 112

transport of a substance across epithelial mb through the cytoplasm

Front 113

what type of transport is limited by tight junctions?

Back 113

paracellular transport (across epithelial mb)