What is the function of 70 percent of alcohol for the specimen had been stored for a long time?

A 70 percent alcohol solution is effective as a preservative and disinfectant for specimens stored for a long time because it provides optimal penetration and denaturation of proteins, helping to prevent degradation. The water content in the solution aids in the absorption of alcohol into tissues, allowing for better fixation and preservation of cellular structures. Additionally, this concentration is effective in killing a wide range of microorganisms, which helps maintain the integrity of the specimen during prolonged storage.