Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Bio 1113 > Chapter 6: Lipids and Membranes > Flashcards

Chapter 6: Lipids and Membranes Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

What is diffusion and how does it occur?

A

Movement of any molecule down its concentration gradient. It occurs spontaneously without any energy

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

What is turgor pressure and why is it important to plans?

A

The pressure produced by water coming into a cell due to a hypotonic solution. The cell is able to be rigid and retain water

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

How does facilitated diffusion work?

A

Channel proteins or carrier provide a doorway for certain polar molecules and ions to pass

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

How does LDL get increased?

A

A diet high in saturated fats

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

What does increased HDL lead to?

A

More cholesterol excretion

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

How many sodiums are moved out of the cell and how many potassiums move in the cell in the sodium-potassium pump?

A

3 sodiums move out and 2 potassiums move in

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

What type of protein is a GLUT-1 transporter?

A

Carrier protein

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

Why are saturated fats solid at room temperature?

A

They can pack close together due to their linear structure

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

Which fats are considered “healthy” fats?

A

Unsaturated fats

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

How does an unsaturated fat differ from a saturated fat?

A

Unsaturated fats have one or more double bonds between C; there is one fewer H on each double-bonded carbon

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

What is active transport?

A

When energy is required

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

What characterizes a steroid?

A

A carbon skeleton with four fused rings

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

What causes cystic fibrosis?

A

Mutant CFTR channels (channel proteins). Chloride on inside can’t fill in the holes on the channels and the channels won’t be open so mucus accumulates outside the cell

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

How do cotransporters work?

A

They use the power of ions moving down their gradient to move a molecule against its gradient

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

What molecules can easily cross the selectively permeable membrane?

A

Small nonpolar molecules like hydrocarbons, CO2, and O2

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

What happens at equilibrium?

A

The ions on both sides are balanced and there is no net movement, but the ions still continue to move across

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

What are peripheral proteins?

A

Membrane proteins that are loosely bound to the surface of the membrane and often interact with exposed surface of integral proteins

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

Why are unsaturated fats liquid at room temperature?

A

They can’t pack as close together due to their bendy structure

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

What is the key characteristic that all lipids share?

A

Hydrophobic

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

What do double bonds between C in unsaturated fats cause the fatty acid chain to do?

A

Kink and bend in a different direction

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

What does hypotonic mean?

A

Less solutes are in the environment

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

How does a glycerol bind with a fatty acid?

A

Dehydration

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

What are aquaporins?

A

Channel proteins that allow water to flow through at an extremely high rate

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

How specific are cotransporters?

A

Very specific. Both molecules must be present for it to work

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is HDL?

A

High density lipoprotein. Removes LDL from the bloodstream. “Good” cholesterol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

How often does the plasma membrane move?

A

It moves laterally 10^7 times per second

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What influences membrane permeability?

A

Fatty acids of different lengths and saturation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What does isotonic mean?

A

The environment outside the cell is the same as inside

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What are essential fatty acids and how do we get them?

A

Fatty acids we must get through our diet because our bodies don’t produce them. Omega 3s, Omega 6, Fish oil, etc.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

How is it determined what can pass through a channel protein?

A

What amino acids are expressed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

How does soap work?

A

Soap dissolves in water and orients themselves w the oil/grease, agitation separates oil from surface, and it is washed away in running water. It takes advantage of hydrophilic and hydrophobic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Which fats are solid at room temperature and which are liquid at room temperature?

A

Saturated are solid and unsaturated are liquid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

How does a saturated fat differ from an unsaturated fat?

A

Saturated fats have no double bonds between C and have the most H atoms as possible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Which fats clog arteries and why?

A

Saturated fats because they can pack close together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What are trans fats?

A

Mostly man-made fats that exist naturally in very small amounts. They are created by adding hydrogen atoms to unsaturated fats. They were an attempt to create healthy saturated fats

36
Q

Are lipids polymers?

A

No, they are clumped together because they are hydrophobic

37
Q

Do carrier proteins change shape?

A

Yes

38
Q

What happens if the environment is hypertonic to the cell?

A

Water moves out of the cell

39
Q

What is cystinuria?

A

Defect in carrier protein that transports cysteine across membrane of kidney cells leading to bladder stones. Very common in dogs

40
Q

What are the 3 ways molecules move across the membrane?

A

Diffusion, facilitated diffusion, and active transport

41
Q

What types of steroids are made from cholesterol?

A

Sex hormones (estrogen and testosterone)

42
Q

What molecules require a membrane protein to cross the selectively permeable membrane?

A

Ions and polar molecules

43
Q

Do channel proteins change shape?

A

No

44
Q

What does hypertonic mean?

A

More solutes are in the environment

45
Q

What are the functions of membrane proteins?

A

Transport, enzyme activity, signal transduction, cell-cell recognition, intercellular joining, attachment to the cytoskeleton and extracellular matrix (ECM)

46
Q

Is it easy for the membrane to flip-flop?

A

No, it is very rare

47
Q

What are fats more commonly known as?

A

Triglycerides

48
Q

What are the three types of lipids that are the most biologically relevant?

A

Steroids, fats, and phospholipids

49
Q

What are integral (transmembrane) proteins?

A

Membrane proteins that span the membrane with segments both inside and outside the cell

50
Q

How do longer hydrocarbon chains effect membrane permeability?

A

They decrease permeability because molecules have to travel further when the chains are longer

51
Q

What is the difference between HDL and LDL?

A

HDL removes LDL that clumps in the bloodstream. The difference lies in what other proteins are present

52
Q

What does cholesterol do?

A

It is a precursor from which other steroids are synthesized. It is also an important component of the cell membrane

53
Q

What can happen with a mutation to the aquaporin-2 gene?

A

Nephrogenic diabetes insipidus. Can’t absorb water the way they’re supposed to and have to always have water with them

54
Q

What does secondary active transport (cotransport) do?

A

Uses the gradient created by an ATP powered pump to power the transport of a molecule against its gradient

55
Q

What proteins are used in facilitated diffusion?

A

Channel proteins and carrier proteins

56
Q

What type of transport is facilitated diffusion?

A

Passive transport

57
Q

How do proteins arrange themselves in the membrane?

A

Hydrophilic parts are on the outside and the hydrophobic parts and in between the bilayer

58
Q

What do all different types of cells contain?

A

Different membrane proteins

59
Q

When are ion pumps used?

A

Active transport

60
Q

What do HDL and LDL stand for?

A

High density lipoprotein and low density lipoprotein

61
Q

What does the word hydrogenated indicate?

A

Trans fats

62
Q

What is osmosis?

A

The diffusion of water across a semipermeable membrane

63
Q

How do viruses infect certain cells?

A

They need certain receptors to bind to

64
Q

What happens during active transport?

A

Energy (ATP) is used to move molecules against their concentration gradient

65
Q

Why do we use trans fats?

A

They were designed as a healthy alternative to saturated fats, but they turned out to be worse for us than saturated fats

66
Q

What types of molecules use facilitated diffusion?

A

Polar molecules and ions

67
Q

What does amphipathic mean? What molecule is amphipathic?

A

It has two different regions with distinct properties (hydrophilic and hydrophobic). Phospholipids are amphipathic

68
Q

How are trans fats made?

A

Taking an unsaturated fat and getting rid of the C double bonds or changing the configuration to end with an unsaturated fat with the properties of a saturated fat

69
Q

What are the two parts of a phospholipid?

A

Hydrophilic phosphate head and hydrophobic fatty acid tails

70
Q

Do membranes have the same mosaic everywhere?

A

No, it is different everywhere

71
Q

How do phospholipids orient themselves in a membrane?

A

The tails face in and the heads face out

72
Q

What do ion pumps do?

A

Maintain electrochemical gradients and membrane potentials for nerve impulses

73
Q

Why are phospholipids able to form membranes rapidly?

A

Because they are amphipathic

74
Q

What does the fluid mosaic model imply?

A

The membrane is always moving and made up of more than just phospholipids

75
Q

What happens if the environment is hypotonic to the cell?

A

Water moves into the cell

76
Q

What is LDL?

A

Low density lipoprotein. It clogs arteries. “Bad” cholesterol

77
Q

What are the two molecules that fats are made from?

A

Glycerol and fatty acid

78
Q

What type of lipid is cholesterol?

A

Steroid

79
Q

Is energy used on a cotransporter?

A

No, it is used to create a build up of charge on one side.

80
Q

How do carrier proteins work?

A

Change shape to shuttle molecules across the membrane. They are a doorway with a door. The molecule comes in and the door to the extracellular fluid closes as the one to the interior opens

81
Q

How do you distinguish between steroids?

A

Different chemical groups are attached to the four carbon rings

82
Q

What are the two major types of membrane proteins?

A

Integral (transmembrane) and peripheral

83
Q

What is passive transport?

A

When no energy is required

84
Q

These macromolecules don’t mix with water

A

Lipids

85
Q

Are fats polymers?

A

No

86
Q

How do molecules move down their concentration gradients?

A

From high to low concentration without being effected by other substances

Bio 1113 (22 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions