GV9: Stem Cells & Gene Manipulation

Question 1

what are the three types of stem cells

Answer 1

adult (somatic) stem cells, embryonic stem cells, induced pluripotnt cells

Question 2

what are totipotent stem cells

Answer 2

can form all tissues required for an organism including extra-embryonic tissue such as placenta

Question 3

what are pluripotent stem cells

Answer 3

can form all cells comprising an adult organism

Question 4

what are multipotent stem cells

Answer 4

can form a limited number of cell types

Question 5

what are unipotent stem cells

Answer 5

can only form one type of cell

Question 6

what are self-renewal stem cells

Answer 6

when a stem cell divides, at least one of its daughter cells is also a stem cell

Question 7

where are adult stem cells found in the body

Answer 7

brain, cornea, retina, dental pulp, intestines, blood/bone marrow, skeletal muscle, skin

Question 8

what are the characteristics of adult stem cells

Answer 8

can proliferate; multipotent or unipotent; located in tissues in areas called ‘stem cell niches’; important in organ and tissue homeostasis; difficult to identify and culture

Question 9

how are adult stem cells used

Answer 9

bone marrow transplants, stem cell treatment for MS, artificial skin grafts, corneal transplants, stem cell treatment for age-related macular degeneration

Question 10

what are the characteristics of embryonic stem cells

Answer 10

continue to proliferate indefinitely, pluripotent, form tumours when injected into immuno-compromised mice

Question 11

what are human ES cells

Answer 11

culture more complex, need layer of ‘feeder’ cells, still defining factors required FGF-2 and nodal important, grow more slowly

Question 12

how does cloning work

Answer 12

remove nucleus from egg, inject in nucleus from somatic cell and expose to electrical shock, need to produce cocktail of chemicals that drive the egg to divide past 16 cell stage