Enzymes do not increase delta G of a reaction. Delta G remains the same in an enzymatic reaction. Enzymes fasten reactions by either decreasing the activation energy or by producing binding energy and in both of these cases there is no impact on delta G so it remains the same, that is why statement 1 is incorrect. Statement 2 is correct because most of the enzymes are made up of proteins which is a polymer of amino acids. Statement 3 is also correct because enzymes lower the activation energy as already mentioned. Statement 4 is correct too. Enzymes are very specific to the kind of substrate to which they bind. Enzymes are bond specific, stereo specific & group specific of the substrate to which they bind.
