6 LABOEATOEY MANUAL 



roots store food, as in the dahlia, we have the fleshy 

 fibrous or fascicled roots. Sketch one of each of the 

 above kinds of roots. 



Exercise 57. Roots as Orguns of Absorption. 

 Object : To study root hairs and the path of liquids 

 through the root. 



Apparatus 



Petri dishes Carrot 



Blotting paper Eosin solution 



Eadish seeds 



Directions : A. Line the bottom of a petri dish with 

 blotting paper. Moisten it thoroughly and scatter over 

 it a half dozen radish seeds. Cover and set aside for 

 forty-eight hours. At the end of that time examine 

 the roots which have been formed. The fine hair-like 

 growths found along the surface are called root hairs. 

 Are they found on all parts of the root? What is the 

 condition of the tip of the root ? The little yellow 

 portion over the tip of the root is the root cap which 

 protects the delicate portion of the root tip. 



Make an accurate drawing showing root hairs and 

 root cap. 



The mineral foods for plants are dissolved in the soil 

 water. These substances enter the roots by diffusion 

 through the root hairs. 



B. Make a longitudinal section of a carrot or any 

 other good tap root. How many different regions do you 

 distinguish? The central portion is the woody part, 

 outside of which is the cortex. Surrounding the whole 



