Stem Cells

Question 1

What is a stem cell?

Answer 1

A stem cell is a primitive cell that gives rise to a [differentiated, specialized daughter cell] and
self-renews into a more
[stem cells]

Question 2

T/F: Stem cells can functionally reconstitute a given tissue in vivo.

Answer 2

T.

Question 3

Are stem cells terminally differentiated

Answer 3

no, they are not terminally differentiated

Question 4

How often can stem cells divide? and how fast

Answer 4

They have telomerase; they can divide without limit. However, they undergo a slow division.

Question 5

Which stem cells are tissue specific?

Answer 5

Adult stem cells are tissue specific.

Ex. A stem cell in the liver will only produce liver cells.

Question 6

The proliferative potential of a stem cell is called ________

Answer 6

potency

Question 7

3 types of proliferative potential

Answer 7

1. Totipotency
2. Pluripotency
3. Multipotency

Question 8

Totipotency
Type of stem cell:
Location:

Answer 8

the ability for a single cell to give rise to all kinds of organisms, including embroyonic and extraembroyonic tissue.

Type: embryonic stem cell
Location: totipotent cells are located in the zygote

Question 9

Pluripotent
Type of stem cell:
Location:

Answer 9

Pluripotent can give rise to all cells of the embryo and adult tissues.

Type of stem cell: embryonic stem cell
Location: Pluripotent cells are located in the blastocyte

Question 10

Mulitpotent
Type of stem cell:
Location:

Answer 10

Multipotent cells can only give rise to any cell in a SPECIFIC lineage.

Type of stem cell: Adult stem cells
Location: Multipotent cells are located in various tissues

Question 11

Pluripotent stem cells can be isolated from:

Answer 11

the inner cell mass of a blastocyte 7 cultured into an embroyonic stem cell , which can make any cell type

Question 12

Can multipotent stem cells give rise to all cells?

Answer 12

NO.

The can only give rise to cells in a specific tissues

Question 13

_________ stem cells has increased potential for therapeutics

Answer 13

Pluripotent

Question 14

Founder stem cells

Answer 14

Founder cells are constantly present in organs and have a fixed number. Founder stem cells determine the size of an organ via signaling. Thus, they have a finite number of division.

Question 15

Transit Amplifying Cells

Answer 15

Transmit amplifying cell is not a stem cell.
Transit amplifying cell has differentiated from a stem cell.

Transit amplifying cell is formed when a stem cell replicated: forms another stem cell and a transitt amplifying cell.

it has a finite number of divisions

Question 16

What is the difference between stem cells and transit amplifying cell?

Answer 16

1. TACs are not stem cells, they’re more differentiated and are pushed to become the target cell. Stem cells, on the other hand, are undifferentiated
2. Stem cells can divide an unlimited number of times
   Transit amplifying cells have a limited number of divisions.

Question 17

What is the purpose of transit amplifying cells?

Answer 17

growth control

Question 18

Are transit amplifying cells committed?

Answer 18

Yes. they are more specific and will become a cell of a certain lineage.

Question 19

To have a steady pool of stem cells, what happens?

Answer 19

To have a steady pool, 50% of our daughter cells must remain as stem cells and retain original DNA.

the other 50% can differentiate.

Question 20

What processes occur to create a steady pool of stem cells?

Answer 20

1. Divisional asymmetry

2. Environmental asymmetry

Question 21

Divisional asymmetry

Answer 21

The asymmetric division of a stem cell produces

1. a stem cell with the same DNA
2. A cell that has the ability to differentiate

Question 22

Environmental asymmetry

Answer 22

Division of a stem cell makes 2 identical cells, but 1 is influenced by the environment

Question 23

Immortal strand hypothesis

Answer 23

Proposes that adult stem cells retain their DNA information to reduce genetic errors.

Original strand of DNA is preserved in the stem cell from generation to generation

Second cell gets the newly made strand

Question 24

adult stem cells are ________

Answer 24

multipotent

Question 25

Embryonic stem cells are _______

Answer 25

totipotent | and pluripotent

Question 26

Embryonic stem cells

Answer 26

1. derived from the blastocyst stage of a embryo 2. can proliferate indefinitely. 3. When put back into the blastocyst, they can integrate well with the embryo. However, if they are put back in a later stage, they fail to receive appropriate cues to differentiate properly.

Question 27

Bad thing about embryonic stem cells

Answer 27

Can become a TERTOMA, which have a number of different tissue

Question 28

Genes in pluripotent cells

Answer 28

Research has found that there are genes expressed only in pluripotent cell populations. These include ``` Transcription factors: 1. Nanog 2. Oct4 3. Sox2 4. FoxD3 which are necessary for establishment and maintenance of pluripotent stem cells. ``` & growth factors such as Cripto and GDF3

Question 29

growth factors in pluripotent cells

Answer 29

Cripto | GDF3

Question 30

What can we interpret about gene expression in pluripotent stem cells?

Answer 30

There is a common molecular blueprint of gene expression

Question 31

Adult stem cells

Answer 31

- Found in tissue - Respond to the demands of growth/repair. -gene expression is STRICTLY maintained but can be altered by the environemtn .

Question 32

Do we see terotomas in adult stem cells?

Answer 32

No, they have restricted capacity and growth potential. & because they retain properties of the original tissue and have memory of its developmental hx.

Question 33

In bone marrow, we have 2 types of adult stem cells:

Answer 33

1. Hematopoietic | 2. Stromal stem cells

Question 34

Hematopoietic stem cells

Answer 34

come from bone marrow | can differentiate into blood components (RBC, WBC, platelets

Question 35

Mesenchymal stem cells can become

Answer 35

connective tissues and tissues

Question 36

Cord blood

Answer 36

Undifferentiated and does not require gene manipulation. But ethical barriers?

Question 37

Mesenchymal stem cells are a type of _______, stromal stem cell

Answer 37

multipotent stromal stem cell

Question 38

What are the central strategies for regenerative medicine?

Answer 38

1. Reprogram primary cells into the desired cell type | 2. Use pluripotent cells

Question 39

________ is a serious problem in adult stem cells

Answer 39

immune rejection

Question 40

Inductively pluripotent stem cells: IPS

Answer 40

Reprogram an adult cell back into a pluripotent Done by transcription factors

Question 41

Somatic cell nuclear transfer

Answer 41

remove egg nucleus, add a somatic cell nucleus of a recipient and continue to grow with new DNA.

Question 42

Ethical concerns at research stage: Stoping at the fusion stage

Answer 42

cannot use cells to research

Question 43

Ethical concerns at the rsearch stages: stop at the blastocyst

Answer 43

you can research but run the risk of clones