20. Module 3- Satellite Cells

Question 1

I have to do an abstract on this topic, what it is on?

Answer 1

Satellite cell activation, control and self-renewal

Why do we not run out of stem cells?

Question 2

What are stem cells

Answer 2

Undifferntiated cells

Able to renew themselves via cell division

Give rise to differentiated and specialized cells

Question 3

What is the difference between determination and differentiation

Answer 3

Determination- develops into a precursor for finsihed cells

Differentation- Into a specific cell type

Question 4

What are totipotent stem cells?

Answer 4

Precursor to all cells

Can become anything

Question 5

What are blastocyst containing pluripotent stem cell

Answer 5

Next step from totipotent cell, strating to limit range of change

Still have a wide range of potential

Question 6

Give three examples of determined stem cells?

Answer 6

Heamopioetic- turns into blood cells

Nueral stem cells- turns into neural cells

Mesenchymal stem cells- Turns into bone cells

Satelite cells (bonus!)- muscle cells

Question 7

What is the role of stem cells in adults?

Answer 7

Maintenece of tissue

repair of tissue

growth of tissue

plasticity of tissue (change fibre types)

Question 8

What are the fates of stem cells

Answer 8

Quiescence (resting)

Proliferate (grow further stem cells)

Specilisation (differentiation)

Apoptosis (death)

Question 9

Discuss the cell cycle

Answer 9

Stage one mitosis- production of daughter cell

G1/Gap 1- gap between mitosis and DNA replicaiton.

S- synthesis stage

Gap 2- preperation for next step of mitosis

Question 10

Where are quiescent cells in the cell cycle

Answer 10

G1/G0 phase

“arrested” in this phase

Question 11

When does death typically occur in the cell cycle?

Answer 11

G1

Question 12

What criteria is required in order for the progresion of the cell cycle

Answer 12

Growth factos/cytokines
Cell to cell contract

Nutreient content
DNA integrity/error free

Question 13

What controls cell cycle progression

Answer 13

Cyclins- cyclic proteins whose concetrations influence cell cycle progression

Cell cycle checkpoints

Question 14

What are the purpose of stem cells in the muscle?

Answer 14

Allow muscle to change size

Allow cell to change numbers

Allow muscles to change fibre type

Allow musces to change metabolic characteristics

Allow for remodelling and regeneration

Question 15

Discuss the steps of differentiaiton to form myotubes

Answer 15

Mesodermal stem cells

Determined myoblasts (forms quiescent satellite cells)

Differentiated myotubules

Question 16

How are satellite cells involed in repair and regeneration

Answer 16

Macrophages recycle/remove debris

Satellite cell starts to divide

Form and rebuild new muscle fibres

Re-synthesis of sarcomeric protein

Question 17

What is the myonuclear domain principle?

Answer 17

Each myotubule is controlled in a small region by each myonuclei

Question 18

How are satellite cells involved in hypertrophy?

Answer 18

Satellite cells are recruited for increased muscle volume as well as more myonuclei

Question 19

How can a satellite cell give rise into cells that are non-identical

Answer 19

Perpendicular division allows for cell division in which cells divide with one daughter cell going into the muscle and the other cell staying in the basal lamina