<P> Embryonic stem cells ( ES cells or ESCs ) are pluripotent stem cells derived from the inner cell mass of a blastocyst , an early - stage pre-implantation embryo . Human embryos reach the blastocyst stage 4 -- 5 days post fertilization , at which time they consist of 50 -- 150 cells . Isolating the embryoblast , or inner cell mass ( ICM ) results in destruction of the blastocyst , a process which raises ethical issues , including whether or not embryos at the pre-implantation stage should have the same moral considerations as embryos in the post-implantation stage of development . Researchers are currently focusing heavily on the therapeutic potential of embryonic stem cells , with clinical use being the goal for many labs . Potential uses include the treatment of diabetes and heart disease . The cells are being studied to be used as clinical therapies , models of genetic disorders , and cellular / DNA repair . However , adverse effects in the research and clinical processes such as tumours and unwanted immune responses have also been reported . </P>
<P> Embryonic stem cells ( ES cells or ESCs ) are pluripotent stem cells derived from the inner cell mass of a blastocyst , an early - stage pre-implantation embryo . Human embryos reach the blastocyst stage 4 -- 5 days post fertilization , at which time they consist of 50 -- 150 cells . Isolating the embryoblast , or inner cell mass ( ICM ) results in destruction of the blastocyst , a process which raises ethical issues , including whether or not embryos at the pre-implantation stage should have the same moral considerations as embryos in the post-implantation stage of development . Researchers are currently focusing heavily on the therapeutic potential of embryonic stem cells , with clinical use being the goal for many labs . Potential uses include the treatment of diabetes and heart disease . The cells are being studied to be used as clinical therapies , models of genetic disorders , and cellular / DNA repair . However , adverse effects in the research and clinical processes such as tumours and unwanted immune responses have also been reported . </P>
what is the origin of es cells in development
what is the origin of es cells in development
the inner cell mass of a blastocyst , an early - stage pre-implantation embryo
the inner cell mass of a blastocyst , an early - stage pre-implantation embryo