THE SEED PLANTS 307 
PROBLEMS 
1. In what ways are the seed plants the most complex of all plants? 
2. What different kinds of structures in various seed plants may 
remain dormant throughout drought or winter, and later continue the 
growth of the individual plants to which they belong? 
3. Show ten ways in which the seed-plant habit of storing food in 
seeds and elsewhere is important to industries. What four plants are 
most valuable for their stored food? 
4, What plant products are being used as substitutes for animal 
products, as cottolene for lard, etc.? Are there good reasons against 
such substitution ? 
5. How may man vary the amount or quality of food stored in 
plants? 
6. What cases are there in which man has varied plants until they 
would probably be unable to maintain themselves in nature if unpro- 
tected? 
7. What is meant by the statement that the angiosperms are the 
youngest and most successful group of plants? 
