Brainscape's Knowledge GenomeTM

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


See full index

SG Molecular > Lecture 34: Stem Cells > Flashcards

Lecture 34: Stem Cells Flashcards

1
Q

Define stem cell

A

A primitive cell that can either self-renew or give rise to more specialized cell types

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

______________ refers to the ability of a cell to give rise to all cells of an organism, including embryonic and extraembryonic tissues (cells which support embryonic development)

A

Totipotency

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

______________ refers to the ability of a cell to give rise to all cells of the embryo and subsequently adult tissues

A

Pluripotency

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

What is the primary example of a pluripotent cell?

A

Embryonic stem cell

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

_________________ refers to the ability of a cell to give rise to different cell types of a given lineage

A

Multipotency

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

What is the primary example of a multipotent cell?

A

Adult stem cells

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

What is the overall hierarchy of stem cells?

A

Totipotent
Pluripotent
Multipotent

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

Endoderm, mesoderm, and ectoderm cell lines are considered to be _____________ embryonic stem cells

A

Pluripotent

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

The zygote is considered to be a _____________ embryonic stem cell

A

Totipotent

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

If the adult organ needs to be renewed, ____________ stem cells can divide as stem cells giving rise to one daughter cell that remains a stem cell and a set of cells that have a set number of transit amplifying divisions

A

Founder

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

True or false: each organ or tissue has a fixed number of founder cell populations programmed to have a fixed number of divisions

A

True

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

What defines the size of large final structures?

A

Founder stem cells because they have a fixed number of divisions

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

What controls the founder stem cell population?

A

Short range signals from things like growth factors

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

Are founder stem cells totipotent, multipotent, or pluripotent?

A

Multipotent, they are considered to be adult stem cells

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

True or false: transit amplifying cells can divide an unlimited number of times

A

False, they are programmed to divide a LIMITED number of times

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

How do stem cells become frequently dividing transit amplifying cells?

A

Founder stem cells become TACs when they leave the basal layer and are incorporated into the layers above

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

Characteristics of stem cells include:

Not terminally _____________
Can ____________ without limit
Undergo ___________ division

A

Differentiated
Divide
Slow

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

When stem cells divide, what are the two resulting cells?

A

One cell with stem cell characteristics, one with the ability to be differentiated

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

Are adult stem cells tissue specific?

A

Yes

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

Out of a steady pool of stem cell population, precisely 50% must remain as stem cells. What two processes accomplish this?

A

Divisional asymmetry

Environmental asymmetry

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

Which type of asymmetry in the maintenance of stem cells involves asymmetric division leading to 2 cells - one with stem cell characteristics and another with factors that give it the ability to differentiate?

A

Divisional asymmetry

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

Which type of asymmetrical division relating to the maintenance of stem cells produces 2 identical cells, but the environment influences/alters one of the cells to become terminally differentiated?

A

Environmental asymmetry

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

What two processes work closely in sync to maintain our stem cell pool?

A

Asymmetric division and independent choice

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

What hypothesis states that stem cells of some tissues selectively retain original DNA.

A

Immortal strand hypothesis

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

The immortal strand hypothesis postulates that the original strand of DNA is preserved across generations of stem cells that retain their stem cell characteristics. So what happens with the other stem cell, and why is this hypothesis important?

A

The other cell gets a newly synthesized strand

This is important because the stem cell will not obtain genetic errors due to getting a newly synthesized strand

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

What are the 5 types of stem cells?

A
  • Embryonic
  • Adult
  • Fetal
  • Cord blood
  • Induced pluripotent
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What type of stem cells can become any tissue?

A

Embryonic

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

What type of stem cells are tissue-specific?

A

Adult

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

What type of stem cells are multipotent adult stem cells that reside in the liver and have become progenitor cells for a subset of tissues?

A

Fetal stem cells

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

What type of stem cells come from a fully developed organ so they are not pluripotent?

A

Cord blood stem cells

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

What type of stem cells come from adult cells so they are not embryonic, but they are pluripotent. These are considered the best case scenario when legal/ethical considerations have to be made in terms of harvesting stem cells.

A

Induced pluripotent stem cells

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

All political and ethical issues aside, what type of stem cell is most ideal for a therapy for damaged brain tissue?

A

Embryonic stem cells - because they can become any tissue needed.

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

Embryonic stem cells are derived from what early embryonic structure?

A

Inner cell mass

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

The cells from the inner cell mass are:

A. Totipotent
B. Multipotent
C. Pluripotent
D. Determined

A

C. Pluripotent

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

What are the 3 different protocols used for ES cell differentiation?

A

Cells differentiated as embryoid bodies (key is that there are no signals to become an organism so they stop dividing)

Cells differentiated on stromal cells

Cells differentiated on extracellular matrix proteins

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

What stage of the embryo are embryonic stem cells derived from?

A

Blastocyst stage - inner cell mass

37
Q

True or false: Embryonic stem cells derived from the blastocyst stage of the embryo are capable of proliferating indefinitely in culture with unrestricted developmental potential

A

True

38
Q

What happens when embryonic stem cells harvested from the blastocyst stage are put back into the blastocyst?

A

They integrate well with the embryo and develop into different cell types with characteristics appropriate for that site (even germ cells)

39
Q

What happens when embryonic stem cells are injected into an embryo at a later stage or into an adult?

A

They fail to receive appropriate sequences of cues for proper differentiation. There is no control mechanism once injected to guide it to a certain spot, so if it lands in an inappropriate location it can become cancer

40
Q

The defining feature of an embryonic stem cell is its ability to differentiated into a wide range of tissues. Therefore, they have the dangerous potential to give rise to disorganized growths called _____________, which may contain tissues like teeth and bone in strange locations

A

Teratomas

41
Q

In order to avoid teratoma formation after embryonic stem cell injections, what precautions can be taken?

A

Make sure you are targeting the right tissues by manipulating the cell culture prior to injection. This is done to stop differentiation so they have less tendency to go back to some other tissue type. Give it as much of a stromal environment as possible.

42
Q

True or false: teratomas have been discovered after ES injection in vivo followed by inappropriate differentiation into cartilage, bone, skin, nerves, gut, and respiratory lining

A

True

43
Q

Which of the following would be most useful in re-programming a stem cell?

A. Transcription factors
B. Growth factors

A

A. Transcription factors

44
Q

Which of the following would be associated with stromal differentiation of stem cells?

A. Transcription factors
B. Growth factors

A

A. Transcription factors

45
Q

Which of the following is associated with outside-in signaling of stem cells?

A. Transcription factors
B. Growth factors

A

B. Growth factors (like FGF or RA)

46
Q

ES cells may be derived at high frequency from good quality embryos. What does the initial serum contain?

A

Medium + mouse or human embryonic fibroblast feeder cells

47
Q

What factor is needed to cause differentiation of ES cells into adipocytes, neurons, and smooth muscle?

A

Retinoic acid

48
Q

Retinoic acid is important for production of different cell types of ES cells. Which of the following is not a cell type requiring the action of RA?

A. Adipocytes
B. Neurons
C. Astrocytes
D. Smooth muscle

A

C. Astrocytes

Astrocytes and oligodendrocytes require fibroblast growth factor

49
Q

There has been recent promising “proof-of-principle” research indicating that ES cells are strong, reliable, and establish pluripotency with a solid theoretical experimental foundation to induce development of specialized cell types. How does this research apply to organ transplantation?

A

It would solve rejection problems

50
Q

There is wide potential for stem cell therapies in US patient populations. What medical condition has the highest number of patients that could potentially benefit from stem cell-based therapies?

A

Cardiovascular disease

51
Q

Successful treatment of the following diseases in animal models was completed with what type of stem cells?

Severe immune deficiency
Diabetes
Parkinson's
Spinal injury
Demyelination
Myocardial infarction
A

Embryonic stem cells

52
Q

The central strategies of regenerative medicine involve harvesting two cell types: primary cells and ESCs (or iPSCs). What is the purpose of harvesting primary cells?

A

These can be reprogrammed into desired cell types and transplanted into a host

53
Q

The central strategies of regenerative medicine involve harvesting two cell types: primary cells and ESCs (or iPSCs). What is the purpose of harvesting ESCs or iPSCs?

A

They can be directed to differentiate into desired cells types and then transplanted into a host

54
Q

Name some of the challenges for regenerative medicine and transplantation therapy:

Production of required cell type in sufficient numbers and _______ form

What _____ to transplant

Delivery and proper __________

Problems of tissue/immune __________

Embryonic or fetal-derived grafts may be __________

Some transplantation sites may be immunologically ____________

A 
Pure
Cell
Integration
Rejection
Immunogenic
Privileged
55
Q

What is the primary advantage of using mature stem cells?

A

Immune response is less likely because patients are using their own cells

They are also partly specialized so they require less coaxing to become specialized cells

56
Q

What are some disadvantages to using mature stem cells?

A

They are only multipotent - so there is limited flexibility

Less common (especially with age), limited longevity, difficult to find and extract

57
Q

What is the primary advantage to early stem cells?

A

Immortal, pluripotent, easy to extract, readily available

58
Q

What are the primary disadvantages to using early stem cells?

A

Immune rejection possible, difficult to control

59
Q

Immune rejection is a serious problem in adult stem cells if they are grafted from a genetically different person, so an identical genotype is needed. What process involves taking the nucleus from a somatic cell of a patient and injecting it into the oocyte of a donor replacing the oocyte nucleus?

A

Somatic cell nuclear transfer

The blastocyst generated from this hybrid oocyte and ES cells is then isolated and can be used in the patient to avoid an immune reaction

60
Q

An alternative approach to stem cell therapy may be better. If adult cells could be converted into ES-like cells by manipulating _______________ directly

A

Gene expression

61
Q

What are the key determinants of ES cell character?

A

Gene regulatory proteins

62
Q

Biochemical comparisons of ES cells with other cell types suggest some candidate genes for direct manipulation of gene expression. What are the 4 potential gene regulatory proteins?

A

Oct3/4
Sox2
Myc
Klf4

63
Q

When Oct3/4, Sox2, Myc, and Klf4 are injected into ______________, they become ES like cells, including the ability to differentiate into other cell types

A

Fibroblasts

64
Q

What is the yield of ES-like stem cells from alternative approaches like direct manipulation of gene expression using regulatory proteins?

A

Low, and these are not identical to ES cells

65
Q

What 4 transcription factors are essential for establishment and maintenance of pluripotent stem cells in the embryo?

A

Nanog
Oct4
Sox2
FoxD3

66
Q

What transcription factor is required for early stages of pluripotent cell differentiation?

A

GCNF

67
Q

What 2 growth factors are found in pluripotent cells?

A

Cripto and GDF-3

68
Q

What type of stem cells reside in tissues and respond to demands of growth or repair?

A

Adult stem cells

69
Q

Proper tissue organization, growth, or repair require that there be ____________ on developmental potential of stem cells. These limits are strictly imposed by powerful molecular restraints on ________ ___________ and are heritable during many rounds of cell division

A

Restrictions

Gene expression

70
Q

An adult stem cell may show relaxation of the molecular restraints on gene expression in an altered environment, possible accounting for __________. Even so, this is observed usually at low frequency.

A

Plasticity

71
Q

True or false: anything that is not an embryonic stem cell is an adult stem cell

A

True

72
Q

What are the 3 primary advantages to harvesting umbilical cord blood for stem cells?

A

Undifferentiated
No ethical problems
No gene manipulation

73
Q

What type of stem cells come from cord blood?

A

Hematopoietic stem cells

74
Q

What type of stem cells one from cord tissue?

A

Mesenchymal stem cells

75
Q

True or false: hematopoeitic and stromal stem cells can become any cell type

A

False

76
Q

What type of stem cells are found in cord blood, bone marrow, and peripheral blood?

A

Hematopoeitic stem cells

77
Q

What type of stem cells are found in Wharton’s jelly, bone marrow, adipose tissue, and tooth pulp?

A

Mesenchymal stem cells

78
Q

What type of mesenchymal stem cell has the natural ability to differentiate into bone, cartilage, muscle, tendon/ligament, adipose tissue, or other potential structure with the proper growth factor applied?

A

Adipose-derived mesenchymal stem cells (AD-MSCs)

79
Q

An example of adult stem cell therapy involves harvesting hematopoeitic stem cells from bone marrow –> transplanting them into cell culture to multiply –> transplanting them into leukemia patient. How do these cells go from pluripotent to the RBCs necessary for the patient?

A

Pluripotent –> multipotent –> myeloid progenitor –> erythrocytes

80
Q

Each type of specialized stem cell has a _________ of its developmental history and seems committed to its fate. This limits its clinical use

A

Memory

81
Q

What are 2 different sources of potential human embryonic stem cells?

A

Somatic cell nuclear transfer (SCNT)

Induced pluripotent (iPS) cells

82
Q

What are the potential sources of eggs used in SCNT? (These are the cells that your somatic cells replace the nucleus)

A

Self, mother, relative, egg bank

83
Q

What are some of the problems associated with SCNT?

A

Inefficient, technically demanding, needs to be available in many or all hospitals

84
Q

How is reprogramming done without using an egg or making an embryo?

A

Combine a pluripotent cell with an adult cell and fuse them; the hybrid cell shows activation of the embryonic genome. You can also inject pluripotent genes into an adult cell and it will then become pluripotent

85
Q

What effect do growth factors have on stem cells?

A

They bind membrane receptors and control TF activation of differentiation genes (main effect is activation of proliferation)

86
Q

What transcription factor turns off TGF signaling temporarily?

A

Noggin

87
Q

Which of the following does not have the potential to develop teratomas?

A. iPS stem cells
B. ES cells
C. EC cells from nuclear transfer
D. Stem cells from fusion of somatic cells with ES
E. All of the above have the potential to form teratomas

A

E

88
Q

Challenges of stem cell maintenance include __________ and ____________ aberrations that can occur at multiple steps of pluripotent stem cell maintenance.

A

Genomic

Epigenomic

SG Molecular (7 decks)

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