478 OrganisiHS Are Products of Heredity and Environment unit ix 



4. If you have a garden, there are many other experiments vou can 

 perform. Find out \v hich flowers self-poUinate. Perform artificial polhna- 

 tion, using all precautions. By self-pollinating for several generations vou 

 may establish pure forms. Do you know why? Cross these forms. These 

 experiments would, of course, extend over several seasons. 



5. Your school is probably in need of charts and other demonstration 

 material for showing the results of various crosses. Prepare some, using 

 college textbooks as the sources of information. 



6. A group of pupils (representing chromosomes) with a string of 

 genes pinned on each, can move themselves about to explain reduction 

 division in dihybrids. You can also show linkage in this way. Can you 

 plan it? 



7. Look up and write a report on how Morgan and his co-workers 

 were able to assign a definite location to genes in the chromosomes of the 

 fruit fly. Consult Snyder, Principles of Heredity, or Scheinfeld, Heredity 

 and You. 



