Muscle Fibres Small 134×320 Medium 267×640 Large 428×1024 Download Tiff Original 1002×2400 | (351.7 KB) Description "Plain muscle fibres. n, nucleus of muscle cell; p, undifferentiated cell protoplasm; p', the differentiated contractile portion of the cell." — Galloway Keywords Fibre, muscle, nucleus, protoplasm Galleries Mammal Anatomy: Internal Organs Source: Thomas Walton Galloway, Zoology A Text-Book For Secondary Schools, Normal Schools and Colleges (Philadelphia: P. Plakiston's Son & Co., 1913) 52