Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Science 22 May 1970:
Vol. 168. no. 3934, pp. 994 - 996
DOI: 10.1126/science.168.3934.994
Prev | Table of Contents | Next

Articles

Structure of the Giant Fibers of Earthworms

Brian Mulloney 1

1 Department of Biological Sciences, Stanford University, Stanford, California

The median giant fiber and the pair of lateral giant fibers that run the length of the ventral nerve cord in earthworms were thought to arise by fusion of the axons of several nerve cells in each segment. The structure of these giant fibers has now been examined with a fluorescent dye injected into single fibers. Each giant axon connects to one cell body in each segment; the giant fibers are not fused axons. In each segment, the median giant fiber has three branches and each lateral giant fiber has five branches. These branches are presumably dendritic. No structural differences between the giant fibers in anterior and posterior regions of the worm seem to account for the functional polarity of the giant fiber system observed in behavioral studies.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Influence of ultraviolet radiation on selected physiological responses of earthworms.
S.-C. Chuang, W.-S. Lai, and J.-H. Chen (2006)
J. Exp. Biol. 209, 4304-4312
   Abstract »    Full Text »    PDF »
Constancy and uniqueness in a large population of small interneurons.
C Goodman (1976)
Science 193, 502-504
   Abstract »    PDF »
Decremental Conduction over "Giant" Afferent Processes in an Arthropod.
D. H. Paul (1972)
Science 176, 680-682
   Abstract »    PDF »


To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)