Abstract
Pea root plastids are able to take up inorganic phosphate in a time-dependent reaction. The rate of uptake is reduced in the presence of triose phosphates, though the kinetics of uptake do not appear to conform to a simple Michaelis-Menten interpretation. Inorganic phosphate taken up by such preparations is lost from the plastids upon addition of triose phosphates. Unlike chloroplasts, root plastids do not appear to accumulate inorganic phosphate above the concentration in the surrounding medium.