30 ROOTS 



an area about one-eighth of an inch in diameter. Run a glass tube through 

 a small section of a wax candle and directly over the small openin};. Now 

 push the wire down the tube and puncture the membrane at the small end 

 of the egg. Fill a wide-mouthed bottle level full of water and set the egg 

 in the top. (Fig. 80.) Note and explain the rise of water in the tube. 



15. Osmosis with a Fleshy Root- — Cut a slice from the upper part 

 of a carrot or other fleshy root; hollow out the centre of the root and 

 fill with sugar. Let stand for twenty-four hours. What has occurred? 

 Explain. 



IG. Cut thin strips, about one-eighth inch thick, of a fleshy root and 

 place in salt water for a few hours. Examine and then place in distilled 

 water for a few hours. Examine and explain. 



QUESTIONS 



1. VVliere do we find the root system of the plant? 



2. What do you understand by geotropism ? 



3. What are the characters of the soil that make it suitable for plant 

 growth ? 



4. What can you say about the different types of root systems of 

 plants ? 



5. What are the functions of the roots? 



6. Is there any difference in the arrangement of the root systems of 

 plants ? Explain. 



7. Upon what is the variation of the root system dependent? 



8. What is the difference between the root system of the radish and 

 that of the turnip? What functions do they serve? 



9. Give a list of plants whose roots are used for food by man and 

 livestock. 



10. Define and give examples of annuals, biennials, and perennials^ 



11. What is the difference between aerial and epiphytic roots. 



12. Name some plants with parasitic roots. 



13. Name some plants with aquatic roots. 



14. Name and locate the three parts of a root. 



15. Explain osmosis. 



16. Why are some fertilizers injurious to plants? 



17. How does air reach the roots of plants? How can the farmer 

 aid plants to secure air? 



18. What is the general direction of root growth? Of stem growth? 



