<prompt> The synthesis of glucose from pyruvate by gluconeogenesis:Occurs exclusively in the cytosol.Is inhibited by an elevated level of glucagonRequires the paicipation of biotinInvolves lactate as an intermediate  <response>: Biotin is the cofactor of pyruvate carboxylase. The carboxylation of pyruvate occurs in the mitochondria whereas the other reactions of gluconeogenesis occur in the cytosol. Glucagon stimulates gluconeogenesis. Lactate is not an intermediate in the conversion of pyruvate to glucose. Ref: Bender D.A. 2011. Chapter 44. Micronutrients: Vitamins Minerals. In D.A. Bender, K.M. Botham, P.A. Weil, P.J. Kennelly, R.K. Murray, V.W. Rodwell Eds,Harpers Illustrated Biochemistry, 29e. 