LABORATORY PRACTICE 



3. Place dry Peas in dry, loose sawdust, occasionally sprin- 



kle well with water, keep in the refrigerator at a low 

 temperature, watch, and examine as in (i), 



4. Make careful notes of any differences observed as regards 



the behavior of the three sets of peas from day to day. 



XL Questions for Summary and Review. 



1. What part of the embryo protrudes first from the seed- 



coats? 



2. In what plants does the caulicle form a loop and appear 



above the ground first? 



3. In what plants does the cotyledon form a loop and 



appear above the ground first? 



4. In what plants do the cotyledons emerge from the 



ground ? 



5. In what plants do the cotyledons remain below the 



surface of the ground ? 



6. In what plants do the cotyledons bring the endosperm 



up above the ground ? 



7. In what plant does the cotyledon remain below the 



ground absorbing nourishment from the endosperm ? 



8. In what plants does the plumule appear above the 



ground first? * 



9. In what plants does the caulicle lengthen considerably? 



10. In what plants does it remain short? 



11. In what plants do the cotyledons turn green, live for 



some time, and act like ordinary leaves? 



12. In what plants does the plumule grow out promptly? 



13. In what plants does it grow out only after some time? 



14. What reasons can you give for the different shapes of the 



cotyledons in different plants? 



15. Why are they different from the adult leaves of the 



same plant? 



