Stem Cells and Cellular Differentiation
All multicellular organisms start as a single cell. This single cell is sometimes called a zygote. A long process of
development is needed to transform the zygote into a fully formed plant or animal. First, it goes through a series of divisions that generates many cells.
As the cells of this early-stage organism, known as an embryo, continue to divide, the cells begin to show differences in their shapes, contents, and
functions. In other words, the cells become specialized. The process that produces specialized cells is cellular differentiation. Cellular differentiation is directed by the genetic information inside the cell. This genetic information is encoded in the cell’s DNA. It is passed from parent to off spring in the eggs and sperm cells.
All multicellular organisms start as a single cell. This single cell is sometimes called a zygote. A long process of
development is needed to transform the zygote into a fully formed plant or animal. First, it goes through a series of divisions that generates many cells.
As the cells of this early-stage organism, known as an embryo, continue to divide, the cells begin to show differences in their shapes, contents, and
functions. In other words, the cells become specialized. The process that produces specialized cells is cellular differentiation. Cellular differentiation is directed by the genetic information inside the cell. This genetic information is encoded in the cell’s DNA. It is passed from parent to off spring in the eggs and sperm cells.
Stem Cells
In animals, a cell that can differentiate into many different cell types is called a stem cell. A stem cell divides into two daughter cells through the processes of mitosis and cytokinesis. Each resulting daughter cell can develop into a different type of cell, based on which parts of its DNA are switched. Stem cells generally occur in clumps that differentiate into different tissue layers, such as epithelial, muscle, and nerve tissues.
In animals, a cell that can differentiate into many different cell types is called a stem cell. A stem cell divides into two daughter cells through the processes of mitosis and cytokinesis. Each resulting daughter cell can develop into a different type of cell, based on which parts of its DNA are switched. Stem cells generally occur in clumps that differentiate into different tissue layers, such as epithelial, muscle, and nerve tissues.
There are two types of stem cells. Embryonic stem cells can differentiate into any kind of cell. Tissue stem cells (sometimes called “adult stem
cells”) exist within specialized tissue. They are only able to differentiate into certain types of cells. For example, tissue stem cells found in bone marrow can differentiate into white blood cells, red blood cells, or platelets.
cells”) exist within specialized tissue. They are only able to differentiate into certain types of cells. For example, tissue stem cells found in bone marrow can differentiate into white blood cells, red blood cells, or platelets.