Fig. 2
From: Fine structure of the cardiac muscle cells in the orb-web spider Nephila clavata
Electron micrograph of the cardiac muscle cells surrounded by scalloped edge of the sarcolemma (rectangles) in the orb-web spider, N. clavata. Each fiber contains multiple myofibrils (mf) and numerous mitochondria (mi), extensive sarcoplasmic reticulum (asterisks) and T-tubules (arrows). Note deeply penetrated plasma membrane (pm), and highly aggregated mitochondria. nu: nucleus. Scale bar indicates 2 μm