  The theoretical predictions of the primordial abundances of elements in the
big-bang nucleosynthesis (BBN) are dominated by uncertainties in the input
nuclear reaction rates. We investigate the effect of modifying these reaction
rates on light element abundance yields in BBN by replacing the thirty-five
reaction rates out of the existing eighty-eight. We have studied these yields
as functions of evolution time or temperature. We find that using these new
reaction rates results in only a little increase in helium mass fraction over
that obtained previously in BBN calculations. This allows insights into the
role of the nuclear reaction rates in the setting of the neutron-to-proton
ratio during the BBN epoch. We observe that even with considerable nuclear
physics uncertainties, most of these nuclear reactions have minimal effect on
the standard BBN abundance yields of $^6$Li and $^7$Li.
