Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Cell Bio > Chapter 11 > Flashcards

Chapter 11 Flashcards

(85 cards)

Start Studying
1
Q

Membranes act as

A

Permeability barriers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

All cells have a

A

Plasma membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

have internal membranes that enclose intracellular compartments (e.g., organelles and vesicles)

A

Eukaryotes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Membrane functions are

A

Receive info from environment, selective import and export, enable cells to change shape, expand

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

The membrane is a

A

thin bilayer + proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Carbohydrates are located on the

A

ECF surface of membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Membrane proteins float in a

A

sea of lipids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

how thick is the plasma membrane

A

5 nm thick

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Membrane lipids __ form bilayers in water

A

spontaneously

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

The lipid bilayer is a __ dimensional fluid

A

2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

The fluidity of a lipid bilayer depends on its

A

composition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

The lipid bilayer is asymmetrical or symmetrical

A

asymmetrical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Lipid asymmetry is preserved during

A

membrane transport

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Membrane lipids have __ head group and __ hydrocarbon tails

A

polar, one or two (hydrophobic)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Membrane lipids form a bilayer in

A

water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Geometry of membrane lipids favors

A

bilayer formation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Phospholipid bilayers __ form sealed compartments

A

spontaneously

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Holes in membranes are __ to minimize interactions of hydrophobic molecules with water

A

rapidly resealed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Membrane lipids move rapidly within one

A

monolayer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

The most abundant lipids in cell membranes are

A

phospholipids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

have a phosphate-containing polar head group

A

phospholipid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

the most abundant phospholipid

A

Phosphatidylcholine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what determines membrane fluidity

A

length and saturation of hydrocarbon tails

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

__ tails promote membrane fluidity

A

short

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Double bonds introduce kinks and __ membrane fluidity
increase
26
Special membrane lipid
cholesterol
27
Cholesterol characteristics
Rigid sterol ring with a polar head group & one short hydrocarbon tail
28
can fill the spaces between neighboring phospholipid molecules produced by the kinks in their tails
cholesterol
29
Tends to stiffen membranes with unsaturated tails
cholesterol
30
phospholipids have what charge
negative
31
Increasing the number of double bonds in lipid tails does what to fluidity
increases
32
Shortening the length of lipid hydrocarbon tails does what to fluidity
increases
33
saturated fats have long or short tails
short
34
Moving veggie oil from room temp to fridge does what to the fluidity
decreases
35
Glycolipids have
carbs on their heads
36
T or F the two monolayers have the same lipids
false, different
37
Lipids are __ arranged between two monolayers
asymmetrically
38
New phospholipids are synthesized by
enzymes bound to cytosolic surface of the ER
39
Enzymes that synthesize phospholipids insert the new lipids into the
cytosolic monolayer of the ER membrane
40
randomly transfer lipids to the lumenal (or extracellular) monolayer
Scramblases in the ER
41
Membrane bilayers move from
ER to Golgi
42
selectively transfer some lipids from the monolayer that faces the lumen to the cytosolic monolayer
flippases in golgi
43
flippases in golgi generate an
asymmetric distribution of membrane lipdis
44
Asymmetry is maintained during
transport and after
45
becomes the extracellular surface of the plasma membrane
lumenal surface
46
Enables membranes to maintain the asymmetric distribution of lipids, proteins, and carbohydrates
lumenal surface
47
The cytosolic surface is
outside
48
The c terminal end is always in the
cytosolic surface
49
provides the barrier function, membrane proteins provide other functions
lipid bilayer
50
Proteins (membrane spanning polypeptide chains) usually cross membranes as an
alpha helix
51
Membrane proteins can be purified using
detergents
52
The plasma membrane is often reinforced by the
cell cortex
53
proteins that are directly attached to the membrane
Integral membrane
54
Transmembrane, monolayer-associated, lipid-linked
integral membrane proteins
55
Can only be removed from the membrane using detergents
integral membrane proteins
56
Non-covalent association with other membrane proteins
peripheral membrane proteins
57
Can be released from the membrane with gentle procedures (e.g. salt)
peripheral membrane proteins
58
what protein is easier to seperate
peripheral membrane proteins
59
__ amino acids form an alpha-helix
20 hydrophobic
60
Polar atoms of the polypeptide backbone are
hydrogen bonded inside the alpha-helix
61
Hydrophobic amino acid side chains on the surface of the helix interact with
lipid tails
62
Multiple a-helices can pack together to form an
aqueous pore
63
Several __ alpha-helices cross the lipid bilayer
amphipathic
64
_ surfaces (green) contact the bilayer
hydrophobic
65
_ surfaces (red) form an aqueous pore
hydrophilic
66
Some transmembrane proteins use several __ to cross the membrane
beta sheets
67
e “beta barrels” form
large pores
68
detergents contain
hydrophobic regions that solubilize lipid bilayer and hydrophilic regions
69
SDS will __ proteins
denature
70
Detergents have __ hydrophobic tail, so they form __ rather than bilayers
1, micelles
71
How to measure membrane protein movement?
Fluorescence Recovery After Photobleaching (FRAP)
72
Look at the behavior of many molecules; Time for recovery reflects the mobility of the molecules
FRAP
73
Look at the behavior of only a few labeled molecules; Distance traveled reflects mobility of molecule
SPT
74
The cells can restrict membrane protein mobility by tethering to
cytoskeleton, extracellular matrix, membrane proteins in another cell, and form junctions to create domains
75
Distinct membrane domains are common in
epithelial cells
76
mediates transport of nutrients from the gut into the cell
Protein A (apical side)
77
mediates transport of solutes from the cell into the bloodstream
Protein B (basal side)
78
form a belt that keeps A and B from mixing
tight junctions
79
The plasma membrane is reinforced by interactions with the
cell cortex
80
good model for studying membrane cortex interactions
red blood cells
81
Major fibrous protein is
spectrin
82
spectrin is attached to
transmembrane proteins
83
Forms a mesh that protects RBC from mechanical damage
spectrin
84
recognize specific oligosaccharides on a neutrophil
lectins on endothelial cells
85
lectins facilitate
attachment to blood vessel wall

Cell Bio (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions