Brainscape's Knowledge GenomeTM

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


See full index

Cell Biology > Unit 1 > Flashcards

Unit 1 Flashcards

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

What do you have to understand in order to have a molecular understanding of cells?

A

Biochemical and genetic analysis of the cell

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

Why are disrupting agents needed to create a cell culture

A

Need to disrupt the intercellular attachments

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

What types of interactions are broken by things like EDTA, trypsin, and collagenases?

A

protein -protein interactions and the ECM

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

How does EDTA disrupt cellular attachments?

A

pulls off Ca ions

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

After treating a tissue with EDTA what are you left with?

A

A heterogeneous population of cells

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

What conditions do cells need to grow in culture

A

Correct pH, essential amino acids, vitamins, growth factors, negatively charged surface, antibiotics and antimycotics

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

What does a negatively charged solid surface mimic?

A

extracellular interctions

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

How are CAMS (cell adhesion molecules) like collagen and fibronectin inactivated?

A

by removing calcium ions

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

Define primary cell culture

A

cells prepared directly from tissues of an organism

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

Fibroblasts secreting collagen
Muscle cells contracting
Nerve cells forming synapses

Are all examples of what?

A

Primary cell cultures displaying the characteristics of the tissue from which they are created

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

Define a cell strain

A

lineage of cells from one initial primary culture. Continued through “passage of cells”

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

What is the approx life of primary cells?

A

50 - 100 doublings

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

Another name for contact inhibition

A

Confluency. THIS IS NOT SEEN IN CANCER CELLS>

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

Characteristics of immortal cells

A

Grow to a high density
Genetically altered
Solid surface not always required
Result from cells undergoing mutations that do not die.
AKA transformed cells (not like bacteria)

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

Which phase do you want to study cells in?

Which phase do mutations start to accumulate?

A

Phase 2

Phase 3

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

What is the definition of a cell line?

What is one problem with studying a cell line?

A

Cells that have undergone transformation and are immortal.

**May not accurately represent origianl cell type

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

True of false: Mouse cells transform much more than human cells

A

True

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

What part of an embryronic blastocyst has the stem cells?

A

ICM (inner cell mass)

Removed (step that destroys the embryo)

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

What are the additional requirements of embryonic stem cells?

A

fibroblast feeder cells (hormones and growth factors)

Cytokines (transcription factors)

**give feeder cells or supply cytokines

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

What are the methods of separating a specific cell type from a heterogeneous mixture of cells?

A

Physical proerties (ex. size / density)

Physiological properties (affinity / charge)

Flow cytometry

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the goal of flow cytometry

A

separate cell types using cell surface antigens

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

How does flow cytometry separate cells using antigens?

A

make “tags” that only attach to the antigens on one specific cell type.

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

For “polar” cells (epithelial) what does the apical surface do?

A

Passes materials

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

For “polar” cells (epithelial) what does the laterial surface do?

A

touches the next cell

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

For “polar” cells (epithelial) what does the basal surface do?

A

attaches to cell surface

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

What are hybridomas used to produce

A

Produce monoclonal antibodies

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

How does this picture relate to B cells and antibodies

A

Polyclonal antibodies are created in B ells agains multiple epitopes of a protein (antigen)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

A monoclonal antibody is created by ______________against a ______________________.

A

Single B cell

Single epitope

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

What is this picture illustrating?

A

Formation of hybridomas.

Fuse mutant (immortal) mouse myloma cells that can’t survive on selective medium with mouse B cells that have been exposed to antigen X (and therefore are making antibodies against antigen X).

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

What does Monastrol do?

A

inhibits microtubule - based moto kinesis - 5

This is needed to separate poles of mitotic spindle

**Tested as anti-tumor drug

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

What parts of the microscope are responsible for magnification?

A

collector

condenser

mirror

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

Cell doctorine by S and S

A

All plant and animal tissues are aggregates of individual cells

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

What is the size range of an animal cell

A

10 - 30 micrometers

5X smaller than the smallest particle visible to the naked eye

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is the limit of traditional light microscopes

A

The resolution of light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Why is there limitation to light waves being used for microscopy?

A

a beam of light can’t probe structures small than its wavelength. so lambda sets resolution

lambda of violet light = 0.45 nm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Define resolution

A

minimium distance between 2 distinguishable objects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Condenser vs. Objective

A

Condenser focuses light on specimen

Objective collects light (cone) to create an image

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Best resolution of a light scope

A

0.2 micrometers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What are the three types of methods that can be used to improve light microscopy resolution?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What are the optical methods to improve light microscopy

A

Brightfield Scopes

Phase Contrast Scopes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What are Physical and Biochemical Methods for improving light microscopy

A

Fixation

Embed specimen

Section

Staining techniques

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What are the advantages to bright field microscopy

A

simple

inexpensive

no staining

image live cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What do you have to add in order to create a phase contrast microscope

A

annular diaphragm

phase plates

These combine refracted and unrefracted light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

How does phase contrast microscopy work

A

Different parts of cell have different refractive indexes.

the anular diaphragm increases light on specimen

the phase plate alters light by 1/4 lambda

Uses polarized light to create ALMOST 3D pictures

Can use living cells!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What materials can be used to “fix” cells?

A

cross - linking agents

(glutaraldehyde and formaldehyde)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What does fixation do to cells?

A

cross links macromolecules (free amino groups)

kills cells

partially perabilizes cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

How do cellular stains stain different parts of the cell

A

use charge to bind

positively charged stains will adhere to negatively charge groups

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

In order to “see” the sample under a fluorescent microscope what is needed?

A

A filter that blocks all wavelengths other than the emission wavelength

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What is the light source for a fluor. scope

A

laser

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

what do you have to add to create a fluor scope

A

dichroic mirror

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

How can you see more than one color with direct fluor staining

A

overlay images from using multiple dyes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

Ion senstive fluorescent dyes can

A

help observe cell movements

different colors in different concentrations of ion

Ca ions start / involved in many cellular processes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

What is the primary antibody binding?

What is the secondary antibody binding?

Why do you need secondary antibody?

A

Primary: binds to X

Secondary: binds to Fc **not X

the fluoroflor destroys about half of the primary antibody. Secondary amplifies the signal.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

Double label fluor. microscopy allows you to

A

see location of 2 proteins (WRT eachother)

Ex.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

Epitope tags are added to proteins through

A

Transormation (like GFP)

Antibody is made against the EPITOPE not the protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

GFP allows what

A

locatlization of proteins in living cells

64
Q

T or F: deconvolustion fluor. micro can create a 3D image

A

True. By consolidating data taken from multiple slices / images

65
Q

Confocal microscopy includes what

A

laser scanning micro (for static object)

Spinning disc (dynamic event)

66
Q

Laser scanning confocal micro addresses what problems

A

can use thick specimen (focus light from only one plane and reject light from others)

Gives info on location of organelles wrt eachother (lost in regular b/c of flat image)

67
Q

T or F:

LSCM can create 3D images of thick specimens without sectioning

A

True

68
Q

How does spinning disc lscm work?

A

spread laser light on 1st disc

light focused on pinholes in 2nd disc (spins)

multiple points on specimen are illuminated at once

lights up entire specimen

69
Q

Two photon excitation micro uses what

A

2 lower energy photons out of visible spectrum

No light scattering!

70
Q

What can you see with 2 photon excitation microsocpy

A

cells up to 1 mm deep in live specimen

live brain images.

71
Q

What is total internal reflection fluor micro used for

A

single focal plane (eg. cells growing on cover slip)

most light is reflected back through the specimen

72
Q

What does FRAP allow you to see

A

movement of molecules in real time

73
Q

How does FRAP work

A

Hit samples with a laser at the excitation wavelength and the flurofor will eventally stop fluoresceing

Turn off laser

watch where bleached proteins move

74
Q

How does FRET work

(Fluorescence Resonance Energy Tranfer)

A

Determines if two molecules are close together or interacting in the cell

Pairs of fluorofor molecules. Donor emits at acceptor excitation wavelength.

See different colors depending on how close molecules are. Have to be closer than 10nm

75
Q

WHat are the different types of super resolution microscopy

A

Structured illumination microscopy

Stimulated depletion microscopy

photoactivated localization microscopy

Light sheet microscopy

76
Q

Structured illumination microscopy (SIM) gives you what resoltuion?

How does SIM work?

A

up to 100 nm

Passes up theoretical optical limit of resolution using math / computer programs

Illuminate specimen in stripes / rotate. Create a picture without interfenece patterns.

77
Q

What is the resolution range of STED

(Stimulated emission depletion microscopy)

How does STED work?

A

resolution = 30 nm

Scan the sample with laser / donut beam. Combine to increase resolution

78
Q

What is the resolution of photoactivated localization miroscopy (PALM)?

How does PALM work?

A

resolution up to 5 nm

Merge 1000s of images, but a few GFPs are excited in any given picture.

Use only the “highest level” fluor in each pic

79
Q

How does light sheet miroscopy work?

A

illuminate one plane (light sheet) at a time and repeat to get 3D image.

Can be used in living tissue / live specimen

80
Q

Why do electron microscopes give such a higher level of resolution?

A

decrease wavelength (electron vs. light) means increased resolution.

wavelength for electrons is 0.005 nm

D = 0.61* lambda / (N*sin alpha)

81
Q

Steps to prep sample for TEM

A

Fixation with glutaraldehyde and osmium tetroxide

Embedding sample (epoxy)

Sectioning (50 - 100 nm thick)

Negative staining

82
Q

How do heavy metal stains work for TEM?

A

heavy metal stains are electron dense so electrons can’t pass through. Structures appear dark.

Different organelles pick up the stain differently.

Lots of stain = lots of deflected electrons

83
Q

How does immuno electron microscopy work?

A

primary antibody binds to protein of interest

primary antibody bound to gold atom

gold is electron dense and appears very dark

84
Q

T or F

Cryo-electron microscopy is a type of transmission electron mmicroscopy

A

True

85
Q

How does cryo EM work?

A

Like a CT scan

No stain, No fixation

Rotate sample stage, collect multiple pics, merge

Gives 3D picture at atomic level

86
Q

What is the overall process to separate cellular organelles?

A

Homogenize tissues

Differential centrifugation

density gradient centrifugation

Mass spectrometry

87
Q

What methods can be used to break open cells without destroying organelles?

A

ultrasonic vibrations (sonication)

tissue homigenizer

high speed blender

force through pores of a filter (8 micrometer)

88
Q

What needs to be added to whole cell extract before separating organelles?

A

Protease inhibitors

89
Q

Differential Velocity Centrifugation

A
90
Q

Density Gradient Centrifugation

A
91
Q

What can mass spectrometry be used for?

A

Identifying different molecules from mixtures.

92
Q

Define lysophospholipid

A

has only one fatty acid chain

93
Q

Define leaflet

A

single layer of phospholipid

94
Q

Identify the functions of the cell membrane

A

selective permeability

compartmentalize cell

localize biochemical reactions

hold membrane proteins

95
Q

Identify the function of membrane proteins

A

respond to signals

energy transduction

ATP synthesis

structural anchors

96
Q

What are the three classes of membrane lipids

A

Phospholipids

Sphingolipids

Sterols

97
Q

Basic structure of a phospholipid

A

Head = choline + phosphate + glycerol

Tail shape dependent on bond type

Kinks in tail from double bonds

98
Q

Phospholipids can have multiple phosphorylation states

Why?

A

1 , 2, or 3 phosphate groups

Abundant in membrane for signal transduction not structure

99
Q

Sphingolipids

A

When attached to carbohydrate are NOT phospholipids

Found in mylein sheeth

100
Q

Sterols

A

found in animals

Cholesterol

Steroid ring makes them flat and rigid (changes properties of membrane)

101
Q

Single layers of phospholipids form

A

Micells

102
Q

Double layers of phospholipids form

A

bilayer sheets

103
Q

How can lipids move in the membrane

A

flip flop: very slow needs flipase

lateral diffusion (side to side)

rotation (change with lipid next to it)

Flexion (cross tails)

104
Q

What happens at the transition temperature of a membrane

A

Above: lipids move and membrane is fluid

Below: lipids become more “solid” and lipid tails straighten and restrict movement

105
Q

Short / unsaturated fatty acids

A
106
Q

Long / saturated fatty acids

A

more stable

Less fluid

more solid

increased energy to melt

107
Q
A
108
Q
A
109
Q

Which property has a larger impact on fluidity

A

degree of saturation

110
Q

How does cholesterol impact membrane fulidity?

A

At 37C dereases fluidity

Below 37 C increases fluidity

111
Q

Where does lipid composition differ?

A

Cytoplasmic face and exoplasmic face

112
Q

Which direction do charged lipids face?

A

cytosol

113
Q

Lipid composition of membrane can determine what things

A

Curvature (also proteins binding)

thickness

charge differences

114
Q

Match up inner / outer leaflet with cytoplasmic / exoplasmic face

A

Inner = cytoplasmic (cytosolic)

Outer = exoplasmic

115
Q

For single layer organelles math faces

A

Cytosolic = outer layer

Exoplasmic = inner layer

*Inner sections of organelles are like the outside of the cell

116
Q

Which organelles have double bilyer membranes?

How many leaflets do these have?

A

Nucleus

Mitochondria

Chloroplast

Have 4 leaflets

*Innermost space is cytoplasmic space

Review enzyme faces!

117
Q

What are the 3 classes of membrane proteins?

A

Integral / Transmembrane

Lipid anchored (tight with lipid in leaflet)

Peripheral (less tightly associated/sit on surface)

118
Q

Typical structure of transmembrane protein?

A

alpha helices span across hydophobic section of the membrane

119
Q

Single Pass Transmembrane Protein structure

A

dimeric

each half (monomer) passes membrane 1X

Hydrophobic residues interact with lipids

120
Q

Multipass transmembrane proteins structure

A

all sections span membrane are alpha helices

molecules can bond to regions and cause conformational change

Ex. 7 pass

11 pass

121
Q

Beta barrel structure

AKA porins

A

roll up to form pores

phobic on outside

philic on inside

122
Q

Lipid anchor protein structure

A

Enire aa chain associated with one leaflet

Associated with lipid anchors

123
Q

What are the 4 types of lipid anchors

A

Myristoyl anchor

Palmitoyl anchor

Farnesyl anchor

GPI anchors

124
Q

Pheripheral membrane structure and removal

A

Associate by non-covalent interactions

Associate with heads of phospholipids

To remove: change salt conc. or pH

125
Q

How can you remove transmembrane proteins

A

Add detergent:

Ionic: will denature proteins

Non-ionic: Will not denature proteins

126
Q

What forms when a detergent is added to membrane

A

Micells of detergent monomers and lipids.

Tails of detergent micells interact with tails of membrane and pull them out

Non-ionic will dissolve protein without forming micells

127
Q

What process was able to determine that proteins are free moving in the membrane?

A

FRAP

Also showed that cells can keep proteins from moving.

128
Q

How do cells keep proteins from moving

A

tight junction

different sides of cells have differnet proteins

confine proteins to lipid rafts

129
Q

How do lipid rafts keep proteins from moving

A

have cholesterol that makes them very rigid

GPI anchored proteins move within the raft but stay in raft

rafts have long saturated fatty acid tails

130
Q
A
131
Q

What are the ways cells immobilize proteins

A

self assemble into large aggregates

interact with extracellular macros

interact with intracellular macros

interaction with proteins on neighbor cell

132
Q

Forms of transport that require energy

A

active transport

coupled transport

bulk movement (endo / exocytosis)

133
Q
A
134
Q

3 classes of protein pathways through membrane

A

channels (gated or open)

transporters (uniporter, symporter, antiporter)

atp powered pumps

135
Q

K= partition coefficient

Relationship between K and ability to cross membrane

A

Increase K = more permeable becuase more soluble in lipids

136
Q

Why do proteins move molecules across membranes faster?

A

remove rate limiting step of interaction with membrane

Facilitated diffusion is specific, fast, happens in a limited region of the cell

137
Q

How does the cell keep GLUT 1 active

A

Turns glucose into glucose 6 phosphate as soon as it enters the cell

138
Q

How do different cell types all use GLUT trasporters?

A

They express different types of GLUT transporters that have different affinites for glucose / other molecules

139
Q

Two key types of uniporters

A

Glucose (GLUT)

Aquaporins (not beta barrel)

140
Q
A
141
Q

Identify the classes of active transporters

A

P class (ions)

V class (H ions)

F class (H ions)

ABC superfamily

142
Q

V class vs. F class pumps

A

V class generate low pH (high H conc) in vaculoes and lysosomes

F class work in reverse from V and drive ATP synthesis (mitochondria)

143
Q

Na / K Pump

A

Pump 2 K into cell

Pump 3 Na out of cell

Works by changing confirmatio and affinity for ions

144
Q

How do ABC Superfamily proteins work?

A

Fliip substances across leaflets and out of cell

Have flipase activity

Can pump chemo drugs out of cells.

145
Q

How do you treat congestive heart failure

A

inhibit Na/K pump to increase Ca conc in cells

146
Q

how does coupled transport work?

A

use energy from gradient to move a substace against gradient

E not from atp

move 2 substances at once. one up and one down

147
Q
A
148
Q
A
149
Q
A
150
Q
A
151
Q
A
152
Q
A
153
Q
A
154
Q
A
155
Q
A

Cell Biology (3 decks)

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