STUDY 2. 
ROOTS AND THEIR MODIFICATIONS. 
A. Fibrous Roots. 
Desirable specimens are seedlings of the radish, bean, 
corn, oat, etc. 
1. The large single root which continues the radicle 
end of the caulicle in the bean, corn, and other 
seeds is a primary root, which may or may not have 
branches. The cluster of roots having their origin 
from the radicle end of the caulicle in the oat seed 
are multiple primary roots. Those roots having 
their origin from any other part of the plant body 
than the radicle end of the caulicle, excepting 
regular branches of primary roots, are secondary 
roots. 
2. With m. study young roots which have not been 
growing in soil. What isthe form of the tip (root 
cap)? Why? 
3. Where are the minute structures (root hairs) found 
most abundantly ? 
4. Make the necessary drawings to show the result of 
study. 
5. With lp. study the root cap. What is its structure? 
6. The outer layer of cells of the root is the epidermis, 
the central portion is the central cylinder (stele), and 
between these is the cortex. Irom which portion 
do the root hairs have their origin ? 
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