46 STUDIES OF PLANT LIFE. 
7. What is the form and structure of the root hairs? 
How are they related to soil particles ? 
8. Make a drawing of a young root to show parts as 
named in 5, 6, and 7. 
9. Study a cross-section of an older portion of a root. 
Draw and designate its parts. 
B. Storage Roots. 
1. In the parsnip, turnip, and sweet potato, how do the 
forms differ? Do soil conditions probably produce 
such variations? If so, how? 
How do storage and fibrous roots differ ? 
Are they spherical, elliptical, or conical in form ? 
Draw and name the forms. 
Of what does the food storage consist ? 
Experiments 5 and 7. 
C. Life Problems. 
1. How and why does the root system penetrate the 
soil ? 
2. How and why does soil cling to the roots? 
3. What must be the condition of exterior food material 
(nutriment) to be usable ? 
4. Where is the region for the upward path of nutri- 
ment? 
ss Experiment 11. 
on 
Why do plants have different forms of roots ? 
6. What is the origin and purpose of the food material 
in storage roots ? 
7. Where does the linear growth of a root occur? Why ? 
Experiment 20. 
8. What is the origin and purpose of the acid secretion 
by roots ? 
Experiment 12. 
