Final answer:
Regaud's fluid and Moller's fluid are types of fixatives used in tissue processing for histology in the field of medicine and biology.
Step-by-step explanation:
In the field of medicine and biology, Regaud's fluid and Moller's fluid are types of fixatives used in tissue processing for histology. These fixatives help preserve the structure of tissues and cells by preventing decay and enzymatic activity.
Regaud's fluid is a mixture of formaldehyde, picric acid, and acetic acid. It is commonly used to fix the testes and ovaries. Moller's fluid, on the other hand, is a mixture of formaldehyde, picric acid, acetic acid, and ethanol. It is primarily used for fixing glands and lymph nodes.