48o BIOLOGY AND HUMAN LIFE 



6. In what ways are the gametes of rockweed like each other ? In 

 what ways are they different ? 



7. How does the relation between a flowering plant and its offspring 

 differ from the relation between a rockweed and its offspring ? 



8. How can animals influence the distribution of plants ? What ani- 

 mals in your region do ? 



9. What are the advantages of having seeds remain close to the base 

 of the parent plant ? What are the disadvantages ? 



10. What is there about the common weeds of your region that enables 

 them to spread over a wide area? 



11. What parts of the plant besides the ovary may be related to seed 

 distribution ? 



12. In w^hat ways can we control the multiplication of plants that are 

 useful to us ? 



13. In what ways can we control the multiplication of plants that are 

 harmful to us ? 



14. What different methods of plant propagation are used in your 

 community for commercial purposes? 



15. What use is made of cell division in one-celled plants ? 



16. How does the weeping willow extend its territory? 



REFERENCE READINGS 



Densmore, H. D. General Botany, pp. 154-159, Vegetative Repro- 

 duction. 



Ward, C. H. Exploring Nature, pp. 75-78, ''Scattering the Seed" (from 

 Selina Gaye's "The World's Great Farm"). 



Waters, H. J. Essentials of the New Agriculture, chap, xxxiii, The 

 Fruit Crop. 



Fanners' Bulletin 461, Grape Propagation. 



Farmers' Bulletin 887, Raspberry Culture. 



Farmers' Bulletin ijdg, Bridge Grafting. 



Farmers' Bulletin iiyi, Growing Annual Flowering Plants. 



Farmers' Bulletin 750, Roses for the Home. 



Farmers' Bulletin 1311, Chrysanthemums for the Home. 



Farmers' Bidletiii 1370, Dahlias for the Home. 



Farmers' Bulletin 1381, Flerbaceous Perennials. 



