Select key terms are defined below.  For a complete list of glossary terms please refer to the book.

Chapter 1 Key Terms

Stem cells - biological cells capable of self-renewal and that have the capacity to differentiate into a variety of cell types; present within most, if not all, multi-cell organisms.

Theory of hematopoiesis - all blood cellular components are derived from a common precursor stem cell.

Spleen colonies - visible lumps present within irradiated immune-deficient mice due to the injection of bone marrow cells.

Neurogenesis - the generation of neurons and glial cells.

Microneurons - small-caliber mature interneurons.

"No new neurons" central dogma - Ramon and Cajal's hypothesis that mammals are born with a preset number of neurons and that there is no growth or generation of new neurons after birth.