What is the purpose of fixation in tissue processing?

The purpose of fixation in tissue processing is primarily to preserve tissue structure. Fixation involves the use of chemical agents that stabilize proteins and lipids, effectively preventing autolysis and decay. This process helps to maintain the morphology of cells and tissues as they appear in their living state, allowing for accurate interpretation of histological sections under a microscope.

By preserving the tissue structure, fixation ensures that the details necessary for diagnosis, such as cellular architecture and pathological changes, can be visualized effectively after the tissue is embedded in paraffin and sectioned. The choice of fixative and the fixation time can significantly impact the quality of the preserved tissue, influencing subsequent staining techniques and analyses.

While fixation may have some secondary effects, such as contributing to the way tissue might interact with stains (which could superficially be related to enhancement of color), this is not its primary purpose. Additionally, while fixation helps maintain the tissue's size and dimensions by stabilizing its structure, it does not specifically reduce size, nor is the removal of excess materials its main function. Therefore, the correct answer emphasizes the importance of preserving the intricate architecture of tissues for further study.