Brainscape's Knowledge GenomeTM

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


See full index

Biology 1 > Cell Membranes and Functions > Flashcards

Cell Membranes and Functions Flashcards

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

What is the foundation of membrane structures?

A

Phospholipids

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

What do phospholipids include?

A

Glycerol phospholipids and sphingolipids

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

Where are sphingolipids?

A

Found throughout the body, primarily in nerve cell membranes. Make 25% of the lipids in the myelin sheet.

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

What is a myelin sheet?

A

Thin tissues of fat that insulates nerve tissues and nerve cells.

Helps transport signals quickly through the nervous system.

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

What is globular proteins?

A

Rounded, spherical proteins that takes different shape are inserted in the lipid bilayer.

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

What is the composition of the fluid mosaic model?

A

Mosaic of proteins floats in or on the fluid bilayer like bonds on a pond.

Integral proteins fitted into phospholipid bilayer. (Embedded Protein)

Channel proteins are also embedded in the phospholipid layer, with a tunnel/tube like appearance. (Transport Protein)

Peripheral are found on the surface but still integrated.

Surface proteins on the surface.

Hydrophilic heads can be seen on the outside, while hydrophobic tails make the interior to create a sandwich.

Carbohydrates like glycolipids are depicted as green strands.

Globular protein are round spheres embedded into the phospholipid layer.

Glycoproteins are attached to globular protein.

Globular protein + glycoprotein = Carbohydrate

Cholesterol within the hydrophilic tails.

Extracellular fluid top side (outside), cytoplasm bottom side (inside cell).

Phospholipid: hydrophilic head + hydrophobic tail

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

Why is the fluid mosaic model fluid?

A

The molecules in the model are still able to move around. The proteins are not static. Some level of fluidity.

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

When carbohydrates attach to the lipid bilayer what is it?

A

Glycolipids

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

What are cell surface markers in the phospholipid bilayer?

A

Glycoproteins and glycolipids

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

What is the interior protein network?

A

Peripheral or intracellular membrane proteins?

ex: spectrins

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

What are transmembrane proteins?

A

Integral membrane proteins

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

What are the types of transmembrane proteins

A
  1. Carriers
  2. Channels
  3. Receptors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What do spectrins do to the cell?

A

Give shape to cells.

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

What do clarithins do?

A

Helps in cell mediated endocytosis

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

Endocytosis

A

Mechanism cell uses to bring more molecules into the cell.

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

What do glycoproteins help with?

A

Self recognition

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

What do glycolipids help with?

A

Tissue recognition

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

How do we study the cell membrane?

A

Transmutation electron microscope and scanning electron microscope.

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

What is lipidomics?

A

Largescale study of pathways and networks of cellular lipids. Grouped by number of molecules and biological functions of the different lipids.

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

How many lipids are there in cells?

A

1000 distinct lipids

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

How are lipids divided into three classes?

A

Lipids are divided into:

  1. Glycerol Phospholipids
  2. Sphingolipids
  3. Sterols
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is amphipathic?

A

Polar aspect with a non-polar aspect

ex: Polar head = polar + hydrophilic

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

Why are polar heads attached to water?

A

Hydrophilic due to hydrogen bonding of water itself as polar heads hold the layers together.

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

Why are bilayers fluid?

A

Individual phospholipids that make up the bilayer are not static, unanchored proteins move through membrane.

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

What temperate makes membrane more fluid?

A

Warm temperatures > Cold

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

What is the effect of fats on the membrane fluidity?

A

Saturated fats make the membrane less fluid than unsaturated fatty acids.

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

What is the lipid composition of ER, Golgi stack, and plasma membranes?

A

Each structure has different lipid compositions.

ex: ER is more fluid than plasma membrane as more unsaturated fats result in a lack of tight packing.

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

What does cholesterol do to the plasma membrane?

A

Introduces fluidity

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

What the functions of membrane proteins (plasma membrane)?

A
  1. Transporters
  2. Enzymes
  3. Cell-surface receptors
  4. Cell surface identity markers
  5. Cell to cell adhesion proteins
  6. Attachments to cytoskeleton
  7. Affect membrane structure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Transporter protein functions

A

Selectively allow certain molecules to pass through the bilayer through its channel.

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

Enzyme protein functions

A

When there is a molecule that cell needs, converts into products to undergo a reaction inside the cell.

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

Cell surface receptors functions

A

Structures that fit into the receptor to release signals into cell.

32
Q

Cell surface identity markers functions

A

Give cells unique identity.

ex: glycoproteins and glycolipids

33
Q

Cell to cell adhesion function

A

Allow cells to attach temporarily or permanently to perform activities together and communicate.

34
Q

Attachment to cytoskeleton function

A

Actin filament attached to protein gives stability as it anchorages to cytoskeleton. Stabilizes organelles.

35
Q

What are anchoring molecules?

A

Attach to the membrane protein to the membrane surface. Molecules that attach to plasma membrane.

Modified lipids.

36
Q

What are the non polar regions of the protein shaped as when embedded in the interior of the bilayer?

A

A helices or B related sheets.

37
Q

Polar regions of protein protrude from the side

A

True

38
Q

What are transmembrane domains ?

A

Cut across the membrane of the cell, membrane spanning region. Made up of hydrophobic amino acids arranged in a helices.

Only need one transmembrane to be anchored in membrane.

39
Q

What is the polarity of the pore created within a non polar region with a transmembrane protein.

A

Polar as it allows water and small polar molecules pass through the membrane.

ex: urea

Cylinder of B pleated sheets in protein secondary structure called a B-barrel

40
Q

What is passive transport?

A

Movement of molecules through the membrane where no energy is required.

41
Q

How to molecules move in passive transport?

A

Molecules move in response to a concentration gradient.

42
Q

What is diffusion?

A

Movement of molecules from high concentration to low concentration. Due to imbalance of concentration, seeks equilibrium.

43
Q

Where will non polar molecules move?

A

Move until concentration is equal on both sides.

44
Q

How do polar molecules move?

A

Move based on size, smaller polar molecules are more permeable.

45
Q

Proteins make the plasma membrane more selective.

A

Permeability

46
Q

What is facilitated diffusion?

A

Molecules cannot cross the membrane easily move through proteins.

47
Q

What are channel proteins?

A

Hydrophilic channels when open.
Molecules moving from higher to lower concentration.

Polar molecules can easily pass through when open.

48
Q

What are carrier proteins?

A

Bind to specific molecules to help cross the membrane. (selective)

Helps transport both ions, other solutes, sugars, and amino acids.

49
Q

What are ion channels?

A

Allows the passage of ions through non polar interior of the plasma membrane? (polar channels)

50
Q

What are gated channels?

A

Open or close in response to stimulus (chemical or electrical)

51
Q

How is direction determined of how molecules move?

A
  1. Concentration of either side of membrane
  2. Voltage differences across membrane (inside/outside)
  3. Gated channel (open or closed)
52
Q

How do carrier proteins move?

A

Movement via diffusion, requiring concentrations difference across membrane.

53
Q

What is saturation?

A

Rate of transport limited by number of transporters as receptors are binded become used up. (limitation of carrier proteins)

54
Q

What is osmosis?

A

Movement of water molecules towards an area with high solute concentration.

55
Q

What is cytosol?

A

Mainly water and dissolved solutes, aqueous area of cytoplasm.

56
Q

What is tonicity?

A

The comparison of two solutions with different osmotic concentrations.

57
Q

What is a hypertonic solution?

A

Higher solute concentration

58
Q

What is a hypotonic solution?

A

Lower solute concentration

59
Q

What is isotonic solution?

A

Same osmotic concentrations

No net movement.

60
Q

What are aquaporins?

A

Specialized channels for water in cell membrane to facilitate osmosis.

61
Q

What are the two types of aquaporins?

A
  1. One that lets only water in.
  2. Allows water and other hydrophilic molecules ex: urea, glycerol
62
Q

Hypotonic solution affect on cell

A

Cell in hypotonic solution gains water, causing to swell and create pressure.

63
Q

What is turgid pressure?

A

Cell wall reach balance of osmotic pressure driving water out.

64
Q

What do contractile vacuoles do?

A

Help remove water out of the cell.

65
Q

Hypertonic solution effect on cells

A

More water inside the cell than outside, therefore water moves out from cell (shrivels cell)

Higher concentration to lower

66
Q

Hypotonic solution effect on cells

A

More water outside cell than inside, therefore water moves into the cell. (cell swells + eventually bursts)

67
Q

What is turgidity?

A

Pressure against cell wall that gives shape to cell wall. Keeps cell wall rigid.

68
Q

What is isosmotic regulation?

A

Keeping cells isotonic with its environment, self-regulation. (marine organisms)

69
Q

What is active transport?

A

Carrier proteins requires energy, using ATP directly or indirectly to fuel transportation.

Used when molecules move against their concentration gradient hby moving from low to high concentration.

70
Q

What are the type of carrier proteins in active transport?

A
  1. Uni-porters (1 molecule)
  2. Sympoters (2 molecules moved in same direction)
  3. Anti-porters (2 molecules moved in opposite direction)
71
Q

What is the sodium potassium pump?

A

Pump obtains extra potassium molecules needed for the cell, and removes extra sodium molecules into cell.

Antiporter moves 3 Na+ out of cell, and brings 2 K+ into the cell.

72
Q

What is phosphorylated?

A

Changes the conformation and shape of the protein pump.

73
Q

What is coupled transport?

A

ATP is used indirectly. Molecules moved at the same time as it uses energy released from movements by diffusion.

74
Q

What is endocytosis?

A

Bulk of substances are moved into the cell, requiring energy. Does this by phagocytosis and pinocytosis.

75
Q

What is phagocytosis?

A

Cell takes in particulate matter (consumes cell)

76
Q

What is pinocytosis?

A

Cell takes in only fluid. (cell drinking)

77
Q

What is receptor mediated endocytosis?

A

Specific molecule taken in after binds to a receptor. Clathrin causes dentation that is a coated pit, once receptor proteins bind with target molecule, clathrin closes to create coated vesicle within cell.

78
Q

What is exocytosis?

A

Movement of substances out of the cell, requiring energy.

Biology 1 (6 decks)

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