Marrow (1 of 2) (IMAGE) NASA/Johnson Space Center Caption This bone marrow shows an increase in fat after a period of immobility. Credit Bone and Joint Research Laboratory, University of Ottawa. Usage Restrictions None License Licensed 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.