Stem Cells
A stem cell divides asymmetrically, i.e. it produces one
daughter stem cell to maintain its pool and another
daughter cell that goes on to differentiate. This strategy is
called the single stem cell asymmetry.
In many organs, stem cell lineages pass from a multipotent stem cell (capable of
forming numerous types of cells) to a committed stem cell that makes one or very few
types of cells to a progenitor cell that is transient in its life, that can proliferate for
multiple rounds and is committed to becoming a particular type of differentiated cell.
What is Totipotent or Totipotency?
A stem cell capable of producing all the cell types of a lineage is said to be totipotent. In
organisms such as hydra, each individual cell is totipotent. In mammals, only the fertilized
egg and first 4 to 8 cells are totipotent, which means that they can generate both the
embryonic lineages (that form the body and germ cells) and the extraembryonic lineages
(that form the placenta, amnion, and yolk sac).
What is Multipotent Stem Cell?
As each germ layer expand and differentiate, resident stem cells are maintained within
the developing tissues. These stem cells are multipotent and function to generate cell
types with restricted specificity for the tissue in which they reside. From the embryonic
A stem cell divides asymmetrically, i.e. it produces one
daughter stem cell to maintain its pool and another
daughter cell that goes on to differentiate. This strategy is
called the single stem cell asymmetry.
In many organs, stem cell lineages pass from a multipotent stem cell (capable of
forming numerous types of cells) to a committed stem cell that makes one or very few
types of cells to a progenitor cell that is transient in its life, that can proliferate for
multiple rounds and is committed to becoming a particular type of differentiated cell.
What is Totipotent or Totipotency?
A stem cell capable of producing all the cell types of a lineage is said to be totipotent. In
organisms such as hydra, each individual cell is totipotent. In mammals, only the fertilized
egg and first 4 to 8 cells are totipotent, which means that they can generate both the
embryonic lineages (that form the body and germ cells) and the extraembryonic lineages
(that form the placenta, amnion, and yolk sac).
What is Multipotent Stem Cell?
As each germ layer expand and differentiate, resident stem cells are maintained within
the developing tissues. These stem cells are multipotent and function to generate cell
types with restricted specificity for the tissue in which they reside. From the embryonic
