Microtubules (IMAGE) Rockefeller University Caption During cell division, microtubules (red) dynamically lengthen and shorten to pull chromosomes to either end of the cell. Credit Lawrence Ruben Laboratory of Chemistry and Cell Biology at The Rockefeller University Usage Restrictions Image may only be used to illustrate research described in an accompanying release. License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.