What is the purpose of dehydration in tissue processing?

Dehydration in tissue processing serves the essential function of removing water from the tissue. This step is crucial because most embedding media, such as paraffin wax, are hydrophobic and do not mix with water. By eliminating water, dehydration ensures that the tissue can be infiltrated and embedded effectively in these media. This process helps preserve the architecture of the tissue and prepares it for the subsequent steps in tissue processing, including infiltration and embedding. Efficient dehydration is necessary to maintain the integrity of cellular structures, making it a foundational step in preparing tissue samples for histological examination.