Microscopic 10x view of a colony of undifferentiated human embryonic stems cells being studied in developmental biologist James Thomson's research lab. The embryonic stem cell colonies are the rounded, dense masses of cells. The flat, elongated cells in between the embryonic stem cell colonies are fibroblasts that are used as a "feeder layer" on which the embryonic stem cells are grown.
UW-Madison University Communications 608/262-0067
Photo by: University of Wisconsin-Madison
Date: 08/01 File#: scan provided