Lecture 6

Question 1

Tissue Maintenance

Answer 1

• Involves molecular turnover and cellular turnover -> involve cell division and death
• New cells can come from stem cell division and differentiated cell division
• Highly specialized cells have no cellular turnover

Question 2

Stem cells

Answer 2

• Can divide indefinitely
• Not terminally differentiated
• Can self-renew
• Can differentiate
• Undergo asymmetric or symmetric division
• Transient amplifying cells divide rapidly to increase cell numbers before final differentiation
• Progenitor cells undergo stepwise differentiation

Question 3

Stem cell niche

Answer 3

• Defined by secreted signal molecule, direct cell-cell contact
• Cell that lose contact with niche differentiates

Question 4

Transplantation experiments

Answer 4

• x-irridation halts blood production
• Transplant of 1 multipoint stem cell can restore all blood cell types

Question 5

Somatic Cell Nuclear Transfer

Answer 5

• Don’t need fertilized embryo

Question 6

Induced Pluripotent Stem Cells

Answer 6

• iPS cells can be made from adult cells
• Use OSKM to influence transcription