504 Introduction to the Study of Science 



REVIEW QUESTIONS 



1. By what three methods may plants be improved? 2. Describe 

 fully the steps necessary in cross-pollination. 3. Within what groups 

 may cross-pollination be effected? 4. What may be the results of 

 cross-pollination of selected individuals of any variety? 5. What 

 are hybrids? 6. (a) What is the usual result of trying to cross al- 

 lied kinds? (6) Mention some instances of successful crossing. 

 7. (a) Mention several plants that come true to seed ; several that do 

 not. (6) How are plants of the second group propagated? 



8. What is a "sport"? 9. Describe the method by which the 

 Wealthy apple was originated. 10. (a) What was the origin of the navel 

 orange? (6) How is it propagated? 11. Can bud variation be pro- 

 duced at will? 12. What two kinds of " sports " occur among plants? 



13. (a) What is the general method of propagating by buds? 

 (6) Describe the particular methods for potato, strawberry, blackcap 

 raspberry, grape, currant, apple. 14. (a) Mention several plants 

 that are often propagated from cuttings. (6) Describe the method. 

 15. (a) Describe the process of budding. (6) Mention several com- 

 mercial plants propagated by budding. 16. Mention some com- 

 mercial plants which are propagated by grafting. 17. What are the 

 advantages of grafting? 18. Can grafting be successful if the stock 

 on which the scion is placed is of a widely different species? If it is 

 of a nearly related species? 19. (a) What is the advantage of select- 

 ing seed? (6) When should it be done? 



SUGGESTIVE QUESTIONS 



1. If bud sports were common, what methods of propagation would 

 be uncertain? 2. (a) Have any new varieties of agricultural plants 

 been originated in your vicinity? (b) Give the story of the origin 

 and propagation. 3. Of the two kinds of flowers in the cucumber 

 vine, which sets fruit? What is the use of the other? 4. Are the 

 pistillate and staminate flowers of the cucumber the same color? Of 

 the corn? Explain. 5. Compare wind-pollinated and insect-polli- 

 nated flowers as to odor and color. 6. (a) What evidence have you 

 that some insects have a sense of smell? (6) Is their choice of odors 

 always the same as ours? Give an illustration. 7. Mention" some 

 fruit the seeds of which are eaten by birds but not digested. What 

 purpose does this serve in the propagation of the fruit? 8. Upon 

 what agencies do plants depend for propagation of their kind? 

 9. What qualities do you find in weeds fitting them to survive but 

 not to serve man's needs? 10. In your observation of the plants 



