What does hyperplasia refer to?

Hyperplasia refers to an increase in the number of cells in a given tissue or organ, which can lead to an enlargement of that tissue or organ. This process can occur as a normal physiological response to certain stimuli, such as hormonal changes or increased functional demand. For example, during pregnancy, the breast tissue undergoes hyperplasia in response to hormonal signals to prepare for lactation.

This definition distinguishes hyperplasia from other processes like hypertrophy, where the size of existing cells increases rather than the number, and atrophy, which refers to a decrease in cell size or number. Additionally, apoptosis is the term used for programmed cell death, which is not related to hyperplasia. Understanding these distinctions is crucial in fields like pathology and histology, where cellular changes can indicate underlying health conditions.