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Flashcards in Final 1 Deck (80)
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1
Q

Cells isolated directly from a particular tissue that do not survive many passages in culture

A

Primary Culture

2
Q

Primary cultures aging and dying

A

Replicative senescence

3
Q

Modified cell line that is the result of alterations in normal cell cycle control mechanisms such as those that occur during cancer

A

Cell lines

4
Q

What does low-speed centrifugation result in

A

Whole cells, nuclei, cytoskeletons

5
Q

What does medium-speed centrifugation result in?

A

Mitochondria, lysosomes, peroxisomes

6
Q

What does high-speed centrifugation result in?

A

Microsomes, small vesicles

7
Q

What does very high-speed centrifugation result in?

A

Ribosomes, viruses, large macromolecules

8
Q

Uses positively charged beads to separate negatively charged molecules

A

Ion-exchange chromatography

9
Q

Uses porous beads that allow larger molecules to flow through

A

Gel-filtration chromatography

10
Q

Uses beads with covalently attached substrate to bind to correct enzyme molecules

A

Affinity chromatography

11
Q

What is SDS-PAGE separate molecules based on?

A

Charge to mass ratio

12
Q

Why is SDS-PAGE mainly based on mass?

A

Protein uniformly coated with SDS which denatures the protein

13
Q

Uses a stable pH gradient to separate molecules based on pH

A

Isoelectric focusing

14
Q

Cut DNA so that there are sticky ends

A

Restriction endonucleases

15
Q

4 steps of PCR

A

Heat to separate strands, hybridization of primers, add free nucleotides, DNA synthesis

16
Q

Use double-stranded plasmid DNA vector to overexpress protein

A

Recombinant protein production

17
Q

2 ways to obtain contrast in light microscopy

A

White light, green light

18
Q

4 types of light microscopy

A

Bright field, phase contrast, DIC, dark field

19
Q

Used to cut tissue into thin sections for use under a microscope

A

Microtome

20
Q

Dye that binds to negatively charged compounds like nucleic acid

A

Hematoxyln

21
Q

Dye that binds to protein

A

Eosin

22
Q

2 ways to overcome out of plane light

A

Computationally-image deconvolution, optically-confocal microscope

23
Q

Acquire images above and below focal plane of interest

A

Computationally-image deconvolution

24
Q

Only illuminate the focal plane of interest

A

Optically-confocal microscope

25
Q

4 super resolution microscopy techniques

A

SIM, STED, STORM, PALM

26
Q

4 functions of protein molecules that span the lipid bilayer

A

Transport of specific molecules through membrane, catalyzing membrane-associated reactions, structural links to ECM, receptors to detect chemical signals in environment

27
Q

The tail of a phospholipid is

A

Hydrophobic, non-polar

28
Q

The head of a phospholipid is

A

Hydrophilic, polar

29
Q

Molecule that has both a hydrophilic, polar end and a hydrophobic, non-polar end

A

Amphipathic

30
Q

Where are new lipid molecules primarily synthesized?

A

Cytoplasmic leaflet of membrane

31
Q

How do lipid molecules travel to the ECM-side of the membrane if flip-flops are so rare?

A

Phospholipid translocators

32
Q

4 movements of phospholipid molecules

A

Lateral diffusion, flexion, rotation, flip-flop

33
Q

Phase transition of a lipid bilayer occurs at lower temperatures if what 2 characteristics of the phospholipids are seen?

A

Short hydrocarbon chains, many double bonds

34
Q

Lipid found in large amounts in PM that has rigid, plate like steroid ring

A

Cholesterol

35
Q

What is the main function of cholesterol in a membrane?

A

Immobilizes regions of hydrocarbon chains, making them less deformable and less permeable to small molecules

36
Q

Sugar-containing lipid molecules found exclusively on noncytosolic side of PM

A

Glycolipids

37
Q

What kind of structures do self-associated glycolipids form?

A

Lipid rafts

38
Q

3 functions of glycolipids

A

Protect cell surface, regulate membrane potential, cell recognition and adhesion

39
Q

Enzymes that cleave phospholipids in specific locations

A

Phospholipases

40
Q

Main way that phospholipid composition is changed quickly

A

Removing or modifying certain lipid headgroups

41
Q

Storage form for fatty acids primarily found in adipocyes

A

Lipid droplets

42
Q

During apoptosis, this phospholipid rapidly tranlocates to the extracellular monolayer to serve as a signal for the destruction of the cell

A

Phosphatidylserine

43
Q

4 types of membrane proteins

A

Transmembrane, Located entirely within cytosol, located entirely on outer surface, bound to either face by noncovalent interactions

44
Q

Computational method to predict membrane spanning alpha helical segments

A

Hydropathy analysis

45
Q

Added to a membrane to isolate membrane proteins from the lipid bilayer

A

Detergents

46
Q

Used to monitor movements of proteins or lipids in membranes

A

FRAP

47
Q

Molecules that can diffuse readily through the lipid bilayer

A

Small, hydrophobic molecules, small, uncharged polar molecules

48
Q

Molecules that cannot diffuse readily through lipid bilayer

A

Ions

49
Q

Where is the concentration of sodium ten times higher?

A

Outside cells

50
Q

2 major classes of membrane transport proteins

A

Carrier, channel

51
Q

Bind to a specific solute to be transported and undergo conformational changes to move the bound molecules across the membrane

A

Transporter proteins

52
Q

Interact with solute weakly, forming an aqueous pore that extends across the membrane

A

Channel proteins

53
Q

What determines the direction of transport of single, uncharged molecules

A

Concentration

54
Q

What determines the direction of transport of a molecule if it carries a charge?

A

Concentration gradient and electrical potential difference across the membrane

55
Q

3 ways to accomplish active transport

A

Coupled carriers, ATP-driven pumps, light-driven pumps

56
Q

4 types of ATP-driven pumps

A

P-type, ABC, V-type, F-type

57
Q

3 types of coupled carriers

A

Uniporter, symporter, antiporter

58
Q

Example of P-type pump

A

SR Ca2+ pump

59
Q

Na-K pump transports how many Na’s and K’s

A

3 Na, 2 K

60
Q

2 transporters that an epithelial cell uses to ingest glucose

A

Na+-glucose symporter, Na-K pump to reestablish sodium concentration levels

61
Q

2 important features of ion channels

A

Ion selectivity, not continuously open - gated

62
Q

3 stimuli that affect the opening of ion channels

A

Change in voltage across a membrane, mechanical stress, binding of ligand

63
Q

Situation in which there is no net flow of ions across a membrane

A

Resting membrane potential

64
Q

What is primarily responsible for generation of a membrane potential

A

K+ leak channel

65
Q

Amino acids lining the pore a channel that are arranged in such a way that they provide energetically favorable interactions with a particular ion

A

Selectivity filter

66
Q

Conformational changes within the subunits of a channel that rearrange the location of the transmembrane domains to restrict access to the opening of a pore

A

Channel gating

67
Q

K+ channel is a _____ of identical subunits

A

Tetramer

68
Q

Cl- channel is a _____

A

Dimer

69
Q

Water channels

A

Aquaporins

70
Q

How is ion passage blocked in aquaporins?

A

Energetically disfavoring removal of ion’s hydration shell

71
Q

Part of a nerve that conducts signals away from the body towards distant target

A

Axon

72
Q

Shorter branches that project from a nerve, providing enlarged surfaces for the reception and detection of signals

A

Dendrites

73
Q

How is an action potential triggered?

A

Depolarization of PM which causes voltage-gated Na+ channels to open

74
Q

How are action potentials propagated?

A

Na+ channels open in a wave down a nerve

75
Q

How does a nerve maintain unidirectional action potentials

A

Na channels are inactivated and K+ channels become activated, so the cell is overwhelmed by K+

76
Q

How is a membrane repolarized after an action potential?

A

K+ channels reset the membrane by moving potassium of of the neuron

77
Q

Compound the helps conduct nerve impulses faster

A

Myelin

78
Q

Non-myelinated regions of a nerve

A

Node of Ravier

79
Q

3 excitatory neurotransmitters

A

Acetylcholine, glutamate, serotonin

80
Q

2 inhibitory neurotransmitters

A

GABA, glycine