![This is blank.](https://digitalhistology.org/wp-content/themes/histology-unified/imgs/trans.png)
Large vein (vena cava)
A feature of large veins, like the vena cava shown here, is a significant amount of longitudinally-oriented smooth muscle in the tunica adventitia. In this H and E stained transverse section, the fibers are seen in cross section. The tunica media consists of circularly-arranged smooth muscle and variable amounts of smooth muscle may also be present in the tunica intima. H and E stain, 100x
![Tunica intima <p>A feature of large veins, like the vena cava shown here, is a significant amount of longitudinally-oriented smooth muscle in the tunica adventitia. In this H and E stained transverse section, the fibers are seen in cross section. The tunica media consists of circularly-arranged smooth muscle and variable amounts of smooth muscle may also be present in the tunica intima. H and E stain, 100x</p>](https://digitalhistology.org/wp-content/uploads/2023/10/Or.CV_.V.V-13A-1-ping.png)
Tunica intima
A feature of large veins, like the vena cava shown here, is a significant amount of longitudinally-oriented smooth muscle in the tunica adventitia. In this H and E stained transverse section, the fibers are seen in cross section. The tunica media consists of circularly-arranged smooth muscle and variable amounts of smooth muscle may also be present in the tunica intima. H and E stain, 100x
![Tunica media <p>A feature of large veins, like the vena cava shown here, is a significant amount of longitudinally-oriented smooth muscle in the tunica adventitia. In this H and E stained transverse section, the fibers are seen in cross section. The tunica media consists of circularly-arranged smooth muscle and variable amounts of smooth muscle may also be present in the tunica intima. H and E stain, 100x</p>](https://digitalhistology.org/wp-content/uploads/2023/10/Or.CV_.V.V-13A-4-ping.png)
Tunica media
A feature of large veins, like the vena cava shown here, is a significant amount of longitudinally-oriented smooth muscle in the tunica adventitia. In this H and E stained transverse section, the fibers are seen in cross section. The tunica media consists of circularly-arranged smooth muscle and variable amounts of smooth muscle may also be present in the tunica intima. H and E stain, 100x
![Tunica adventitia <p>A feature of large veins, like the vena cava shown here, is a significant amount of longitudinally-oriented smooth muscle in the tunica adventitia. In this H and E stained transverse section, the fibers are seen in cross section. The tunica media consists of circularly-arranged smooth muscle and variable amounts of smooth muscle may also be present in the tunica intima. H and E stain, 100x</p>](https://digitalhistology.org/wp-content/uploads/2023/10/Or.CV_.V.V-13A-5-ping.png)
Tunica adventitia
A feature of large veins, like the vena cava shown here, is a significant amount of longitudinally-oriented smooth muscle in the tunica adventitia. In this H and E stained transverse section, the fibers are seen in cross section. The tunica media consists of circularly-arranged smooth muscle and variable amounts of smooth muscle may also be present in the tunica intima. H and E stain, 100x
![- Smooth muscle fibers <p>A feature of large veins, like the vena cava shown here, is a significant amount of longitudinally-oriented smooth muscle in the tunica adventitia. In this H and E stained transverse section, the fibers are seen in cross section. The tunica media consists of circularly-arranged smooth muscle and variable amounts of smooth muscle may also be present in the tunica intima. H and E stain, 100x</p>](https://digitalhistology.org/wp-content/uploads/2023/10/Or.CV_.V.V-13A-6-ping.png)
- Smooth muscle fibers
A feature of large veins, like the vena cava shown here, is a significant amount of longitudinally-oriented smooth muscle in the tunica adventitia. In this H and E stained transverse section, the fibers are seen in cross section. The tunica media consists of circularly-arranged smooth muscle and variable amounts of smooth muscle may also be present in the tunica intima. H and E stain, 100x
![- Connective tissue <p>A feature of large veins, like the vena cava shown here, is a significant amount of longitudinally-oriented smooth muscle in the tunica adventitia. In this H and E stained transverse section, the fibers are seen in cross section. The tunica media consists of circularly-arranged smooth muscle and variable amounts of smooth muscle may also be present in the tunica intima. H and E stain, 100x</p>](https://digitalhistology.org/wp-content/uploads/2023/10/Or.CV_.V.V-13A-7-ping.png)
- Connective tissue
A feature of large veins, like the vena cava shown here, is a significant amount of longitudinally-oriented smooth muscle in the tunica adventitia. In this H and E stained transverse section, the fibers are seen in cross section. The tunica media consists of circularly-arranged smooth muscle and variable amounts of smooth muscle may also be present in the tunica intima. H and E stain, 100x
![Image source > <p>This image was taken of a slide from the Drexel University slide collection.</p>](https://digitalhistology.org/wp-content/uploads/2023/10/Drexel-source-ping.png)
Image source >
This image was taken of a slide from the Drexel University slide collection.