The following drawing represents a cardiac stem cell (CSC) lineage commitment and differentiation in mice.
a) List two characteristics of CSC that qualifies them as stem cells.

b) Briefly describe one experiment that would test whether a “test cell” is likely to be a CSC. Note: Your answers may vary.
c) The CSCs have transcription factors such as Oct4 and Nanog and cell surface proteins such as CD90. Which of these proteins would be best to use to purify living CSC from a mixed population that has multiple cell types? Explain your choice.
d) In adults, CSCs reside in defined regions called “niches” and require the Epidermal growth factors (EGF) and Fibroblast growth factor (FGF) for their proliferation (Cell division) and differentiation. You do the following experiments. You ablate the CSCs from mutant mouse embryos 1 and 2. You implant the GFP labeled CSCs from normal mouse embryo into mutant embryos 1 and 2. You observe that the GFP labeled CSCs proliferate and differentiate to form the cells of CSC lineage in mutant mouse embryo 1 but not in embryo 2. Why do the CSCs from a wild–type mouse embryo grow in embryo 1 but not in embryo 2? 

Cardiac Stem cells (CSC) Primordial Cardiac progenitor Early cardiomyocytes CSC lineage Self-renew Mature cardiomyocytes