Regeneration

by Thomas Hunt Morgan

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1901 edition. ...new heads, if they developed at all, only in the region of union. Peebles states that the regeneration of aboral heads takes place only when one component is cut off near the region of union of the two pieces. M In general, it may be stated in regard to these experiments in hydra that when pieces are united in the same direction, that is, by unlike surfaces, a single individual is formed and no regeneration takes place where the union has been made, but when like surfaces are brought together, although perfect union may result, a process of regeneration takes place later, at or near the line of union. Even the presence of cut-surfaces at one or both cut-ends of the united components does not generally affect the result, although, in a few cases, it may change it, in so far that heteromorphic regeneration may take place from one piece. This sometimes leads to a suppression of regeneration at the line of union. The experiments do not show, perhaps, conclusively whether the heteromorphosis of the smaller component is due to the polarity of the larger component effecting a change in the smaller one, or whether the closing of the oral end of the smaller component (by its union with the other) brings about the result. All things considered, it seems to me that the larger compo nent has directly influenced the other. King has found that if two posterior pieces of hydra are united by the oral cut-surfaces, and then after they have fused both pieces are cut off near the line of fusion, there develops from the small piece a single hydra, with a foot at one end and tentacles at the other. If only one of the pieces is cut off near the line of fusion, a new head develops from its oral surface, as Peebles had found. If two anterior ends are united by...

Genres: Science, Biology

128 pages, Paperback

First published September 12, 2013

About the author

Thomas Hunt Morgan Ph.D. (Zoology, Johns Hopkins University, 1890) was an evolutionary biologist, geneticist, embryologist, and science author who won the Nobel Prize in Physiology or Medicine in 1933 for discoveries relating the role the chromosome plays in heredity.

Morgan researched embryology during his tenure at Bryn Mawr College, the sister school of his alma mater. Following the rediscovery of Mendelian inheritance in 1900, Morgan's research moved to the study of mutation in the fruit fly Drosophila melanogaster. In his famous Fly Room at Columbia University, Morgan was able to demonstrate that genes are carried on chromosomes and are the mechanical basis of heredity. These discoveries formed the basis of the modern science of genetics. He was the first person to be awarded the Nobel Prize in Physiology or Medicine for his work in genetics.

During his distinguished career, Morgan wrote 22 books and 370 scientific papers, and, as a result of his work, Drosophila became a major model organism in contemporary genetics. The Division of Biology he established at the California Institute of Technology has produced seven Nobel Prize winners.