<prompt> The specialized mammalian tissueorgan in which fuel oxidation serves not to produce ATP but to generate heat isAdrenal glandSkeletal muscleBrown adipose tissueHea  <response>: Uncouplers will allow oxidation to proceed, but the energy instead of being trapped by phosphorylation is dissipated as heat. Impoant mitochondrial membrane transpoers. 1 PYT pyruvate transpoer; 2 TCT tricarboxylate transpoer; 3 ANT adenine nucleotide transpoer . This is achieved by removal of the proton gradient. The uncoupling of oxidative phosphorylation is useful biologically.In hibernating animals and in newborn human infants, the liberation of heat energy is required to maintain body temperature. In Brown adipose tissue, thermogenesis is achieved by this process. Thermogenin, a protein present in the inner mitochondrial membrane of adipocytes, provides an alternate pathway for protons. It is one of the uncoupling proteins UCP. Thyroxine is also known to act as a physiological uncoupler.Ref: Chatterjee Textbook of Medical Biochemistry; 8th edition; Page no: 234 