mt_01. Visceral smooth muscle tissue (mesenchymal origin)
(Small intestine, hematoxylin-eosin)
1. Identify smooth muscle cell layers in the muscular coat of a tubular organ.
2. Take a closer look at
the structure of smooth muscle cells/fibers in both longitudinal and cross sections:
- longitudinally cut smooth muscle cells are spindle-shaped, have a centrally located elongated nucleus surrounded by cytoplasm containing myofilaments in various orientations. Smooth muscle cells lack striations;
- in the cross section you will see round or polygonal muscle cells of variable diameter. Only a fraction of cross-sectioned smooth muscle cells displays nuclei.
2. Draw
bundles of smooth muscle fibers сut longitudinally and cross-sectionally, and point out:
- 1 - a longitudinal section,
- 2 - a cross section,
- 3 - the cell nucleus,
- 4 - the sarcoplasm.
3. Define and write significant features of the specimen.