The nutrient uptake of an embryogenic and of a non-embryogenic cell line of birch (Betula pendula Roth.) during cell growth and embryo production was studied in suspension culture. The embryogenic and non-embryogenic cell suspensions grew differently in the same medium. The non-embryogenic cell line started to grow without any lag period after the inoculation. It rapidly hydrolyzed sucrose in the medium to glucose and fructose and consumed the glucose as carbon source. The concentration of fructose in the medium decreased only after the depletion of glucose. The embryogenic cell line also rapidly hydrolyzed the sucrose to glucose and fructose, but the monosaccharides were consumed only after the embryos started to germinate after three weeks of culture. Both monosaccharides were then taken up at the same rate.