What does hyperplasia refer to in terms of cellular growth?

Hyperplasia specifically refers to the process of increased cell numbers within a tissue or organ, resulting from cellular division. This increase can occur in response to various stimuli, such as hormonal changes or increased functional demands on the tissue, and is often seen in tissues that have a high capacity for regeneration. For example, hyperplasia is commonly observed in the endometrial lining of the uterus during the menstrual cycle or in the prostate gland.

In contrast, the other options describe different cellular responses: a decrease in cell size is referred to as atrophy; an increase in cell size without an increase in number is known as hypertrophy; and a state leading to cell death pertains to necrosis or apoptosis. Understanding the differences between these terms is vital in the study of cellular regulation and growth.