54 
STUDIES OF PLANT LIFE. 
C. Prominent Leaf Modifications. 
1. 
5. 
Leaves of Sweet or Garden Pea. 
Is the leaf simple or compound? What part has 
become the tendril? Draw and show all its parts. 
Common Locust, Barberry, and Cactus. 
What parts have become spines? Make drawings of 
stem portions showing spines. 
Scales of winter buds and on leafy shoots and under- 
ground stems. 
What parts of the leaf are present? What is their 
structure andarrangement? What is their purpose? 
Storage forms. 
Onion or Lily, Cotyledons of Bean or Pea. 
What parts of the leaf are present, and what forms 
have they assumed ? 
What other leaf modifications are to be found ? 
D. Life Problems. 
1. 
Three important functions of foliage leaves are (a) 
transpiration, () respiration, and (c) photosynthesis. 
(a) What is the evidence and purpose of the loss of 
water from the leaf surface (transpiration) ? 
Experiment 15. 
Explain “ wilting” and how turgor may be restored. 
How is transpiration regulated? Why? 
What is the origin and purpose of the “dew” on 
lants ? 
P Experiment 18. 
How does covering of plants assist in preventing 
them from being killed by “ frost” ? 
(b) What is the evidence of the inhalation of oxygen 
and the exhalation of carbon dioxide (respiration)? 
Experiments 3 and 12. 
