Protein and Respiration in the Apical Region of the Shoot of Lupinus albus

This investigation is a study of differentiation in the apicalregion of the shoot in terms of the protein content and respirationof the dome and of each of the first seven primordia and internodes.The results obtained have been compared with others reportedearlier showing the volumes and number of cells of each morphologicalcomponent of the same system. It has been shown that internodalcells tend to have a higher content but a lower concentrationof protein than primordium cells. As the series is traversedfrom the upper younger to the lower older units respirationper unit protein tends to increase in the primordia. In theinternodes it is highest in the first three, decreases abruptlyfrom the third to the fourth, and then increases again. Frequentlythe values for the dome are intermediate between those for thefirst internode and those for the first primordium. The significanceof these differences is discussed.