Complex sentence: Muscle biopsy examined under the microscope (haematoxylin-eosin stain, zoom 100 ×): the large white areas between the muscle fibers are due to gas formation.
Split into simpler sentences: Muscle biopsy examined under the microscope (haematoxylin-eosin stain, zoom 100 ×). The large white areas between the muscle fibers are due to gas formation.