The mass and density of an organism have a large effect on the organism's locomotion through a fluid. For example, a tiny organisms uses flagella and can effectively move through a fluid it is suspended in. Then on the other scale a blue whale that is much more massive and dense in comparison with the viscosity of the fluid, compared to a bacterium in the same medium. The way in which the fluid interacts with the external boundaries of the organism is important with locomotion through the fluid. For streamlined swimmers the resistance or drag determines the performance of the organism. This drag or resistance can be seen in two distinct flow patterns. There is Laminar Flow where the fluid is relatively uninterrupted after the organism moves through it. Turbulent flow is the opposite, where the fluid moves roughly around an organisms that creates vortices that absorb energy from the propulsion or momentum of the organism. Scaling also affects locomotion through a fluid because of the energy needed to propel an organism and to keep up velocity through momentum. The rate of oxygen consumption per gram body size decreases consistently with increasing body size. (Knut Schmidt-Nielson 2004)
Christopher is a marine biologist. He is studying organisms deep in the ocean and trying to determine the size of the different organisms in a certain region. Since the marine animals live so deep in the ocean, Christopher is unable to see them. Instead, he has to determine their size based on the movement of the water around each organism. He has detected two primary organisms he is interested in: Organism A and Organism B. He only knows that the flow of water around Organism A is a Laminar Flow and the flow of water around Organism B is a Turbulent Flow.
Which organism is larger?