to obtain data that relate the concentration of l-alanine in the xylem vessels and the escape rate of the amino acid , average escape rates per internode were measured and the corresponding concentrations were calculated from the integrated form of the michaelis-menten equation.as the concentration dependence of the escape rate was biphasic , three possible mechanisms were considered , escape being caused by : ( a ) saturable amino acid uptake of cells around the xylem vessels and diffusion into the free space ;
C0001898
alanine
C0002520
amino