spacer gif spacer gif spacer gif spacer gif spacer gif
QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by ROBERTS, A. M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by ROBERTS, A. M.
Social Bookmarking
Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati   Add to Twitter  
What's this?
Journal of Experimental Biology 53,687-699 (1970)
Published by Company of Biologists 1970

Geotaxis in Motile Micro-Organisms

A. M. ROBERTS 1

1 Department of Physics, Guy's Hospital Medical School London S.E.1

1. It is suggested that the principal cause of geotaxis in many motile micro-organisms is a gravity-induced hydrodynamic torque, the size of which depends upon the shape of the organism. The nature of the torque has been investigated using small scale models.

2. An expression for the distribution of organisms in long, vertical columns has been derived.

3. The distribution of Paramecium in long, vertical columns has been determined, and it has been shown that the strength of the hydrodynamic interaction is sufficient to account for the negative geotaxis usually exhibited by this organism. The induction of positive geotaxis in certain circumstances has been considered.

4. The survival value of negative geotaxis for free-swimming organisms in search of food may explain the characteristic shape of many protozoa.

Submitted on June 1, 1970


Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati   Add to Twitter Twitter    What's this?


This article has been cited by other articles:


Home page
 Biol. Bull.Home page
A. M. Roberts
Mechanisms of Gravitaxis in Chlamydomonas
Biol. Bull., April 1, 2006; 210(2): 78 - 80.
[Full Text] [PDF]

Home page
 J. Exp. Biol.Home page
Y. Mogami, A. Yamane, A. Gino, and S. A. Baba
Bioconvective pattern formation of Tetrahymena under altered gravity
J. Exp. Biol., September 1, 2004; 207(19): 3349 - 3359.
[Abstract] [Full Text] [PDF]

Home page
 Plant Cell PhysiolHome page
K. Yoshimura, Y. Matsuo, and R. Kamiya
Gravitaxis in Chlamydomonas reinhardtii Studied with Novel Mutants
Plant Cell Physiol., October 15, 2003; 44(10): 1112 - 1118.
[Abstract] [Full Text] [PDF]

Home page
 Biol. Bull.Home page
Y. Mogami, J. Ishii, and S. A. Baba
Theoretical and Experimental Dissection of Gravity-Dependent Mechanical Orientation in Gravitactic Microorganisms
Biol. Bull., August 1, 2001; 201(1): 26 - 33.
[Abstract] [Full Text] [PDF]

Home page
 J. Exp. Biol.Home page
U Nagel and H Machemer
Physical and physiological components of the graviresponses of wild-type and mutant Paramecium Tetraurelia
J. Exp. Biol., January 3, 2000; 203(6): 1059 - 1070.
[Abstract] [PDF]

Home page
 J Biol RhythmsHome page
T. Roenneberg, G. N. Colfax, and J. W. Hastings
A Circadian Rhythm of Population Behavior in Gonyaulax polyedra
J Biol Rhythms, June 1, 1989; 4(2): 89 - 104.
[Abstract] [PDF]


© The Company of Biologists Ltd 1970