Question 13 of 16
One method to clone a mammal involves nuclear transfer, in which a somatic cell nucleus from a donor mammal is transferred
to a recipient egg cell with its nucleus removed. This method results in few live births overall due to a high prevalence of
developmental abnormalities. Notably, the probability of a live birth is significantly greater for embryos cloned from the nuclei
of undifferentiated embryonic stem cells than for embryos cloned from the nuclei of differentiated somatic cells (Rideout et
al., 2001).
Select the best explanation of why embryos cloned from undifferentiated embryonic stem cells have greater developmental
success than embryos cloned from differentiated somatic cells.
Patterns of epigenetic markers are different in stem cells and somatic cells, with stem cells having epigenetic patterns
more closely associated with early development.
Patterns of epigenetic markers in stem cells and somatic cells are identical, indicating that the observed difference is not
due to epigenetic regulation of development.
Somatic cells are older than stem cells and have accumulated mutations that disrupt normal embryonic development