Which two methods are used to demonstrate nerve cell processes?

• A. Bodian, Holmes
• B. PTAH, Weil
• C. Cresyl echt violet, Crystal violet
• D. Gold sublimate, Borax-ferricyanide

Answer: (A)

Demonstrating nerve cell processes relies on silver impregnation techniques that make delicate neural fibers stand out against tissue. The two classic methods used for this purpose are Bodian and Holmes stains. Bodian stain impregnates axons and neurofibrils with silver, providing clear visualization of nerve fibers and their pathways. Holmes stain serves a similar goal, highlighting nerve fibers and neurofibrils with strong contrast so thin processes like axons and dendrites can be traced through tissue sections.

Other stains listed are not focused on revealing these fine processes. Cresyl echt violet highlights Nissl substance in neuronal cell bodies rather than the extending processes, and Crystal violet similarly emphasizes cellular components rather than fine neural fibers. PTAH and the Borax-ferricyanide–based approach are used for other tissue features and applications, not specifically for demonstrating nerve cell processes.