Stem Cells

Stem Cells

Stem cells are the basic building blocks of all the organs in our body. These are the undifferentiated cells which differentiate into different specialized cell types. When an embryo comes into origin in the womb, then it is considered that it contains a large number of stem cells. These cells convert into various organs and form a fetus. Stem cells have a magnificent property to change itself into any type of cell. They can also divide themselves through mitosis to produce more stem cells. These are found in mammals only.

They are basically of two types, embryonic stem cells and adult stem cells. Embryonic stem cells are the inner cell mass of the blastocysts and adult stem cells are found in various tissues of brain, bone marrow, blood, skeletal muscles, skin and liver. In adults they remain in in active and non-dividing state until the body is attacked by some disease or injury.

Categories on the base of potency

Stem cells are categorized according to their ability to divide into different types of cells. Embryonic stem cell is the most potential as they can convert into almost all types of body cells. Potency of adult stem cell is lesser as compared to embryonic and its potency decreases with age.
Totipotent- They are the most potent and can convert into all possible types of the cells. They are formed due to division of zygote.
Pluripotent- They have a potential little lesser than that of Totipotent one. They are found in the embryo. They are created by embryonic cell division at the beginning of the embryo formation.
Multipotent- they can convert into cells of closely related family. They are a type of adult stem cells.
Oligopotent- they have a low potency and can convert into very few cells. They are also adult stem cells.
Unipotent- they cannot convert into any other type of cell but can divide itself to produce its own type.

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