Angiospcrmous Plants — Flowering Plants 217 



Fused petals {corolla) surround the style, and their tips are recognizable 

 as five blunt teeth. The pollen-producing anthers are united at their 

 edges to form an anther tube around the style. The style extends beyond 

 the corolla tube and the surrounding anther tube and terminates in two 

 protruding stigmas (Gr. stigma, mark). The calyx is represented by 

 two scales (pappus) at the top of the ovary. 



After fertilization (union of male and female gametes) the ovary 

 enlarges and contains one seed. 



QUESTIONS AND TOPICS 



1. List the distinguishing characteristics of the class Angiospermae, subclass 

 Dicotyledoneae, subclass Monocotyledoneae, and the family Compositae. 



2. Learn the meaning, pronunciation, and derivation of each new term used in 

 this chapter. 



3. Discuss the economic importance of angiosperms. 



4. Discuss the distribution and habitats of angiosperms. 



5,. Make a detailed diagram of a typical angiospcrmous plant life cycle, including 

 the various stages in correct sequence, with each labeled correctly. 



6. Describe the sporophyte generation and the gametophyte generation in angio- 

 sperms, including their relative sizes and independence. 



7. Compare the pollination process in angiosperms with the polhnation as it 

 occurs in a gymnosperm such as a pine tree. 



8. Describe the structures and functions of the v^arious parts of a complete flower. 



9. Describe the seed production process of angiosperms. 



10. List the chromosome number in the gametes, sporophyte, and endosperm. 



11. Contrast monocotyledonous angiosperms with dicotyledonous angiosperms in 

 as many ways as possible. 



12. Describe the formation of the pollen tube and its function. 



13. Review all of the plant tissues described in this chapter, including their dis- 

 tinguishing structural characteristics and functions. 



14. Describe the structure and functions of the ovary. Why are angiosperms said 

 to form enclosed seeds? 



15. Contrast what is meant by pollination and fertilization. 



16. Discuss the so-called double fertilization process and its significance. 



17. Define heterospory and give examples from the angiospcrmous plants. 



18. In the botanical sense, contrast a fruit and seed, giving examples of each. 



19. Describe the structure and functions of cambium. 



20. Describe the construction and functions of cotyledons. 



SELECTED REFERENCES 



Bailey and Bailey: Hortus, The Macmillan Co. 



Britton and Brown: An Illustrated Flora of Northern United States, Canada, and 



British Possessions, New York Botanical Gardens. 

 Clements and Clements: Flower Families and Their Ancestors, The H. W. Wilson 



Co. 

 Coulter and Chamberlain: Morphology of Angiosperms, D. Appleton & Co. 



