The female unit of the state penitentiary shall be a separate institution apart from the administration of the main prison and shall remain a separate unit of the department of correction, but governed by the laws, not in conflict with this chapter, as were in force on July 1, 1965, governing the state penitentiary at Nashville, Brushy Mountain Penitentiary, Fort Pillow State Farm, and other penal institutions, reformatories, branches or facilities of the department.