194 Elementary Botany 



20. Describe what happens in the germination of a Bean seed. (1878.) 



21. What requisites are needed for germination ? 



22. Compare the germination of the following seeds : — Broad Bean, 

 Acorn, Cress, Mustard, Pine, Date, and Wheat. 



23. Compare the modes of germination of seeds of the Oak and of the 

 Beech. In what important respects do they differ ? (1884.) 



24. Describe the way in which roots grow. (1877.) 



25. The seeds of Mustard and Cress will germinate on flannel soaked 

 with rain-water. Will they go on growing under these circumstances ? and 

 if not, why not ? (1879.) 



26. When any vegetable material is burned, what constituents go off 

 as gas ? What are left behind ? (1877.) 



27. What are the principal substances which form the food of plants ? 



(1875.) 



28. What part of the food of a plant is taken up by the roots ? (1878.) 



29. Explain how the food is absorbed by the roots. 



30. Of what substances in the plant is nitrogen an essential ingredient ? 

 How does the plant obtain the nitrogen? (1876.) 



31. Why do plants require nitrogen, and in what form do they take it 

 in? (1880.) 



32. Explain the ' rotation of crops. ' 



33. Explain why the root of a turnip first grows aster than the stem, 

 and then stops while the stem grows rapidly. (1877.) 



34. What are the chief differences between a root and a stem ? 

 (1876.) 



35. Suppose a piece of the axis of some flowering plant were shown to 

 you, what appearances would enable you to decide whether it was part of 

 a root or of a stem ? (1882.) 



36. Compare the appearance of a monocotyledonous and dicotyle- 

 donous stem as seen in transverse section. 



37. What is the cause of the ring-like markings seen in the cross- 

 section of a tree-trunk ? (1876 and 1881.) 



38. Describe and explain as much of the texture of a deal plank as can 

 be made out with the naked eye. (1879.) 



39. Explain the difference in the growth of the bark of a tree and that 

 of the wood. (1880.) 



40. What is the structure and use of cambium ? 



41. State generally what is the composition of a vascular bundle. 

 Describe the longitudinal course of the vascular bundles in the stem of 

 any Dicotyledon. (1887.) 



42. Describe a ' runner,' a ' rhizome,' an ' offset,' and give examples. 



43. Give a full account of a Potato, and explain as much as you can 

 structure. (1875.) 



44. Explain why a Potato is considered to be a stem. (1878.) 



45. Describe and explain the structure of an Onion. (1876 and 1880.) 



