Differentiation

Differentiation is a process in biology and cell biology where a less specialized cell becomes a more specialized cell type. Differentiation occurs numerous times during the development of a multicellular organism as it changes from a simple zygote to a complex system of tissues and cell types. Differentiation continues in adulthood as adult stem cells divide and create fully differentiated daughter cells during tissue repair and during normal cell turnover.

Overview

Differentiation dramatically changes a cell's size, shape, membrane potential, metabolic activity, and responsiveness to signals. These changes are largely due to highly controlled modifications in gene expression and are the study of epigenetics. With a few exceptions, cellular differentiation almost never involves a change in the DNA sequence itself. Thus, different cells can have very different physical characteristics despite having the same genome.

Types of Differentiation

There are several types of cellular differentiation. These include:

• Embryonic differentiation
• Adult cellular differentiation
• Sexual differentiation
• Pathological differentiation

Embryonic Differentiation

Embryonic differentiation is the process by which the early embryo, which is a single cell zygote, develops into a complex multicellular organism. This process involves a series of cell divisions and changes in the cells.

Adult Cellular Differentiation

Adult cellular differentiation is the process by which adult stem cells divide and create fully differentiated daughter cells. This process is crucial for tissue repair and normal cell turnover.

Sexual Differentiation

Sexual differentiation is the process by which the undifferentiated reproductive system develops into either male or female reproductive systems. This process is controlled by the presence or absence of certain sex hormones.

Pathological Differentiation

Pathological differentiation refers to the abnormal changes in size, shape, and function that a cell undergoes in response to a disease or injury. This process is often associated with cancer and other diseases.

See Also

• Cell biology
• Epigenetics
• Gene expression
• Zygote
• Stem cell