MICROANATOMY

Detailed explanation-1: -Stem cells are the cells that have an ability to become various types of cells. They are present both during embryonic development (embryonic stem cells) and in the adult body (adult stem cells).

Detailed explanation-2: -A one-cell embryo (zygote) is “totipotent” in both senses; yet, some authors characterize tumors [1, 2] and stem cells [3, 4] as “totipotent, ‘’ based only on the second definition (ie, the ability of these cells to produce a wide range of cell types).

Detailed explanation-3: -Totipotent stem cells. The known and well characterized totipotent stem cells are found only in early embryonic tissues and derive usually from the first few cell divisions after fertilization.

Detailed explanation-4: -Stem cells are special human cells that are able to develop into many different cell types. This can range from muscle cells to brain cells.