2012, ISBN: 9781235780875

Lerner Publishing Group , 2010. hardcover. New. pp. 32 Index The Golden Gate Bridge is an important structure in San Francisco, California. Before this bridge was built, people had to … Plus…

Lerner Publishing Group , 2010. hardcover. New. pp. 32 Index The Golden Gate Bridge is an important structure in San Francisco, California. Before this bridge was built, people had to take a ferry across the dangerous stretch of water to get to Marin County. Now they simply drive across. Just how long is the Golden Gate Bridge? And how did workers build this orange structure? Read this book to find out! Learn about many remarkable sites in the Famous Places series - part of the Lightning Bolt Books collection. With high-energy designs, exciting photos, and fun text, Lightning Bolt Books bring nonfiction topics to life., Lerner Publishing Group, 2010, This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated.1902 Excerpt: ... THE ACCESSORY CHROMOSOME--SEX DETERMINANT? C. E. McCLUNG. Part I. Observations And Comparisons. The peculiar chromatic element discussed under this name in several recent papers is one that gives promise of throwing considerable light upon the nature of the chromosomes. So long as all chromosomes of the nucleus were observed to pass through a cycle of changes apparently identical in each case, there was little chance to gain an insight into their interrelations. With the discovery of the accessory chromosome and the recognition of its true chromosomic character, however, there has been offered an opportunity to draw comparisons and so to formulate conclusions which, in time, are certain to materially increase our knowledge of these most important nuclear structures. In recognition of this fact, and with the hope of hastening such a desirable end, I have devoted some time to the study of the accessory chromosome and have also encouraged students in my laboratory to direct their attention to it. Much material has been collected, and is still being accumulated, in order that as broad a view of the subject as possible could be obtained. Since, however, the difficulties involved in securing and preparing material from widely different forms would unduly delay the attainment of any comparative results, I have confined my studies largely to the Orthoptera. This has been done in the belief that more substantial good can be derived from a thorough knowledge of a limited group than from a superficial acquaintance with a wider field. Once the basic principles underlying the cellular phenomena of one group are discovered, their recognition in other forms will be rendered much easier. As a result of the studies so far pursued, it has been found that individual forms rar... Weight:0.43 lbs, General Books LLC, 2/7/2012 0:00:00<