Why Are Bacteria All the Same Size? (image) Washington University in St. Louis Share Print E-Mail Caption Methicillin-resistant Staphylococcus aureus, or MRSA, are so uniform in size they look like they were made in a factory. How do they do it? Credit CDC Usage Restrictions Please credit CDC Share Print E-Mail 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.