~—. to absolutely dotcraines, The nezt slide shows the effect ef concentration, Ve wore rather surprised, HEernlt Larson mentioned this sang pheronenon yosterday, which ho has observed -- namoly, althousn . noss ee by © o Ha] eb Gosivablie thin? to prevent or decrease the absorp pu with the various isotones it has renerally been considsred the various radio isotoves by co-treatment with the non-radioactive ecarricr clonont. By this co-tveatment, it has always been felt that you dilute the specific activity and, thus, a plant or animal is not going to take uy as mush, You all know this is trues dn the case of icdine in the thyroid. I2 you give iodine -_. -- 127 along with a dose of icdine-151, the ovganism is not , going to concentrate in the thyroid giand as much of the I-131 as if you had not given this carricr alons with it. not hold true for the plants. This does This is a los scale here, so it spans over quite a diversity of concentrations. és you increase the concentraticn, there is a tendency for an increased absorption of the radio element. This simply says that the plant over in hore (indicatin;) has -- well, conparcd to this, it has five orders of magnitude more eloneat in it than over here. if you are studyin? iodine, ° there is fiva orders of magnitude iodino in a plant over in hore (indicating) because we are using the I-151 simply as a tracer. The I-151 or strontiua, or Whatever you ars usin, is kept constant. This is morely the porcentase uptake, The percent: