Q1: If Damkohler number, N_Da >>1, the reaction rate is much greater than the mass transfer rate and the overall reaction is controlled by the rate of mass transfer. In this case, the enzyme reaction can be described as (where C_sb and C_s are the substrate concentration in bulk of solution and at the immobilized enzyme surface respectively. k_s mass transfer coefficient, and a is the surface area of an immobilized enzyme particles)