Fig. 3
From: Fine structure of the cardiac muscle cells in the orb-web spider Nephila clavata
Electron micrographs of the cytoplasmic mitochondria in the cardiac muscle cells in N. clavata. a: Cardiac muscle cells have a lot of myofibrils (mf) and mitochondria (mi) in the cytoplasm. b: Mitochondria are located in the scalloped edge of the sarcolemma (rectangles) surrounding the myofibrils (mf). c: Oval or elliptical shaped mitochondria contains well developed cristae that provide an increase area of surface. d: Bundles of myofibrils and numerous mitochondria are distributed along the long axis of the muscle fiber. cd: intercalated disc, nu: nucleus. Scale bars indicate 5 μm (a) and 2 μm (b-d), respectively