58 CHAP. VI. RELATION OF TURGOR AND TENSION 



A. 



Enhanced rate of ascent of sap 



I 



Gain of water by the organ 

 Increase of Turgor 



Erectile movement of Enhanced rate of growth 



Mimosa leaf. in growing organ. 



B. 



Diminished rate of ascent of sap 



I 



Loss of water 



Decrease of Turgor 



Movement of fall of Retardation of rate of 



Mimosa leaf. growth in growing organ. 



The correspondence between the responsive movement 

 of the leaf of Mimosa and that of variation in the rate 

 of growth as explained above may be summarised as 

 follows : 



. I. An increase or positive variation of turgor due to 

 enhanced rate of ascent of sap induces an erection 

 or positive response of the leaf of Mimosa, and a 

 positive variation or enhancement of the rate of 

 growth. 

 2. A diminution or negative variation of turgor due to 

 withdrawal of water induces a fall or negative 

 response of the leaf, and a negative variation or 

 retardation of the rate of growth. 



