Chapter 40, Problem F40.1A

Summary Introduction

To label:

The given figure with the correct name of the structure.

Introduction:

The arteries and veins are composed of three layers or tunics. The innermost layer, tunica interna is composed of an endothelium of simple squamous epithelial cells and the basement membrane. The middle layer, tunica media is composed of smooth muscle. The outer layer, tunica externa is composed of connective tissue.

Answer to Problem F40.1A

The table below represents the correct labels from Column A to Column B.

Column A	Column B
1.	Tunica interna
2.	Tunica media
3.	Tunica externa

Explanation of Solution

1. Tunica interna is labeled because it is the innermost layer which is composed of endothelium of simple squamous epithelial cells and the basement membrane that establishes a smooth lining next to the lumen of the blood vessel. Hence, this can be correctly labeled with 1.
2. Tunica media is labeled because it is the middle layer between the tunica interna and tunica externa. It is composed of smooth muscle. It is distinguished by its color and transverse arrangement of its fibers. Hence, it can be correctly labeled with 2.
3. Tunica externa is labeled because it is the outermost layer made up of connective tissues that are rich in collagen. It supports tunica media and supported by the elastic external lamina. Hence, it can be correctly labeled with 3.

Conclusion

The table below represents the correct labels from Column A to Column B.

Column A	Column B
1.	Tunica Intima
2.	Tunica Media
3.	Tunica Externa