stem cells

Question 1

what are stem cells

Answer 1

• they’re the body’s repair and regeneration mechanism
• has self-renewal and differentiation capacity

Question 2

describe stem cells in the body

Answer 2

• tissue and blood have their own resident stem cells eg, neural stem cells
• some stem cells can migrate to other areas of body to effect repair eg, mesenchymal stem cells

Question 3

how did the adult body form form a single cell (oocyte)

Answer 3

• cell division (can be symmetric and asymmetric)
• migration (to organise into complex structures)
• differentiation (into specific cell types)
• apoptosis (programmed cell death)

Question 4

state the stem cell commitment hierarchy

Answer 4

• zygote
• embryo
• tissue stem cells
• progenitor cells
• terminally differentiated cells

Question 5

what type of cell is a zygote

Answer 5

totipotent

Question 6

what type of cell is a embryo

Answer 6

pluripotent

Question 7

what type of cell is a tissue stem cell and a progenitor cell

Answer 7

multipotent

Question 8

what type of cell is a terminally differentiated cell

Answer 8

unipotent

Question 9

what type of cell does an embryo make

Answer 9

embryonic stem cells

Question 10

what are embryonic stem cells split into

Answer 10

mesoderm, endoderm, ectoderm

Question 11

describe haematopoietic stem cells

Answer 11

• they’re quiescent (asleep) in bone marrow:
  hypoxic niche (low oxygen tension)
  slow self-renewal
  no differentiation
• activation in blood:
  receive signal from blood
  migration
  expansion- symmetrical cell division
  specification- asymmetrical cell division

Question 12

what can hematopoietic progenitor stem cells be further subdivided into

Answer 12

into multipotent stem cells which can be divided into lymphoid progenitor ( t-cell, B cell, natural killer cell) and myeloid progenitor (neutrophil, monocyte, basophil, eosinophil)