We have studied the impact of chemical composition on the spectrum of stellar population formed in the starburst .
The range of metallicities used - Z = 0.0001 \div 0.05 - 0.1 covers all the compositions observed ; depending on age , wavelength region and IMF used the UV-fluxes differ between extreme compositions at least tenfold , usually more .
Independently of age , UV-fluxes shortwards of Balmer jump monotonically decline with the growth of metallicity .
Optical and especially IR-region are also influenced , at > 1 \mu m fluxes typically differ 10 \div 50 times .
In IR the actually brightest emitting composition gets reversed with age .