Why the myomere geometry and why red vs. white muscle?
(note: much of the discussion below is a summary of some of the elegant research from Larry Rome and his students) The geometry of muscle fibers is intimately related to the fiber type (i.e. color), hence the questions have to be answered simultaneously. Remember, the white muscle is arranged helically, with fibers pointing into or away from the midline at high angles. The red muscle is arranged in a longitudinal band near the junction of the horizontal septa and the skin, so the red fibers make very small angles with the midline. (Click on image to get a bigger picture or here for a nice, printable PDF version) remember the biochemical properties of red vs. white muscle. Red muscle uses the highly efficient oxidative phosphorylation pathway to get ATPs (the high hemoglobin in the abundant blood vessels of red muscle and the myoglobin in the mitochondrial membranes is what gives red muscle its color). The white muscle uses the inefficient glycolytic pathway. The oxidative phosphorylati
