Flashcards in Introductory Lecture Deck (65)
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1
What is the main component of the cell membrane
proteins
2
What is the function of the cell membrane
divide intracellular and extracellular fluid compartments
3
Where is the sodium concentration low
intracellular fluid
4
Where is the potassium concentration low
extracellular fluid
5
Why do cells have a high level of phosphate in the intracellular fluid of the cell
ATP
6
What is an important function of calcium
secondary messenger
7
Where is calcium concentration low
intracellular fluid
8
What is sodium important for the function of
electrically excitable cells
9
Which ions concentration can vary between cell types
chloride
10
Which has more proteins - plasma or interstitial fluid
plasma
11
What is an important pH buffer
bicarbonate
12
What is a positively charged ion called
cation
13
Give examples of anions
phosphate, chloride, proteins and bicarbonate
14
Why is transport of solutes and ions important
critical for function of all cells
15
How many pathways of transport are there
3
16
What are the three pathways of transport
diffusion, transport proteins, and endocytosis
17
Example of simple diffusion
oxygen and carbon dioxide in the lungs
18
What do transport proteins move across the membrane
small molecules and ions
19
Name an example of exocytosis
release of neurotransmitters at the synapse
20
What are the three basic types of protein transporters
channel, carrier and pump
21
True or False - channels are NOT gated
false
22
Name an example of a carrier transporter
sodium glucose co transport protein
23
Name an example of a pump
sodium potassium ATPase
24
Which is a high energy transport protein - channels, carriers or pumps
Pumps
25
What allows pump transport proteins to function
hydrolysation of ATP
26
which transporters are passive
channels and carriers
27
What do channels and carriers require in order to work
driving force
28
What sets up the driving force for channels and carriers
sodium potassium ATPase
29
TRUE or FALSE - sodium moves against its electrochemical gradient into the cell
true
30
True or False - movement of ions by ATPases is fast
false
31
Why is the movement of ions by ATPases slow
ATP requires extra processing
32
How does binding occur in active transport
hydrolysis of ATP leads to conformational change
33
Give an example of a ubiquitous transport protein
sodium potassium ATPase
34
Describe the structure of the sodium potassium ATPase
tetramer with four subunits - 2 alpha, 2 beta
35
How many genes code for the sodium potassium ATPase
2
36
what is the role of the sodium potassium ATPase
maintain a low intracellular sodium concentration, small contribution to resting membrane potential
37
electrogenic definition
charge generating or carry
38
True or False - ALL ion channels are electrogenic
true
39
what can a driving force be
conc grad, potential grad, or both
40
Name some carriers undergo facilitated diffusion
NKCC2, Sodium glucose co transport protein, NaPII
41
Example of secondary active transport protein
sodium glucose co-transport protein
42
meaning of secondary active transport protein
dependant on an ATP process, doesnt use ATP itself
43
Effect of blocking sodium potassium ATPase
inhibition of sodium and glucose into the cell
44
Why does the rate of uptake plateau in the saturation curve
maximum number of transport proteins at full capacity
45
Describe a symporter
transports two ions in the same direction
46
Describe an antiporter
transports two ions in different directions
47
How can you study ion channel function
studying the current generated by ions moving through ion channels
48
Describe the movement of ions through ion channels
through a pore down an electrochemical gradient
49
Which is the fastest transport protein
ion channels
50
How are ion channels divided
selectivity
51
What did Nehr and Sakman do
patch clamp technique - nobel prize
52
What does the patch-clamp technique allow
directly measure the function of ion channels
53
What are the components of the patch clamp technique
silver chlorided electrode, salt solution
54
What is cell attached configuration
high resistance seal between membrane and glass
55
What does the patch clamp technique allow
identification of channels in a membrane, their regulation and their function
56
what can the patch clamp technique allow us to study
mutations
57
What does whole cell configuration allow you to measure
ion flow through channels on the whole cell
58
What does whole cell configuration allow
clamping of the potential membrane of the cell
59
What does open probability vary from
0 to 1
60
What does 0 open probability mean
channel is closed all the time, never opens
61
What is the effect of regulating the open probability
regulates current flow
62
Name the structural families of the channels
Ach receptors, voltage gated potassium channel family, voltage gated sodium spanning unit, Kir, CFTR Cl- channel
63
Which structural families do not have a pore domain
Ach receptor, CFTR Cl- channel
64
Describe the structure of the K+ channel
crystal structure, 4 subunits with central pore down the middle
65
