Admin Table of Contents
What is the outermost layer of the arterial wall?
The outermost layer, which attaches the vessel to the surrounding tissue, is the tunica externa or tunica adventitia. This layer is connective tissue with varying amounts of elastic and collagenous fibers.
What is tunica externa?
Anatomical terminology. The tunica externa (New Latin “outer coat”) — also known as the tunica adventitia (New Latin “additional coat”), is the outermost tunica (layer) of a blood vessel, surrounding the tunica media. It is mainly composed of collagen and, in arteries, is supported by external elastic lamina.
Which of the following is the layer of the blood vessel that is made of tough elastic connective tissue?
tunica adventitia
circulatory system The tunica adventitia, the outermost layer, is the strongest of the three layers. It is composed of collagenous and elastic fibres. (Collagen is a connective-tissue protein.) The tunica adventitia provides a limiting barrier, protecting the vessel from overexpansion.
What are the layers of the arterial wall?
The arterial wall is made up of three distinct layers—an outer layer of tissue (adventitia), a muscular middle layer (media), and an inner layer of epithelial cells (intima); the latter is the one most commonly affected by arteriosclerosis.
What does tunica intima do?
The innermost layer of the vein is the tunica intima. This layer consists of flat epithelial cells. These cells allow fluid to flow smoothly and are interspersed with valves that ensure the flow continues in one direction. This continuous layer of epithelial cells holds cells and fluid within the vessel lumen.
Which tunica has sphincters?
Slightly larger than the typical capillary, the smooth muscle of the tunica media of the metarteriole is not continuous but forms rings of smooth muscle (sphincters) prior to the entrance to the capillaries.
Why are arteries surrounded by an outer layer of elastic tissue?
The outermost layer is the tunica externa or tunica adventitia, composed entirely of connective fibers and surrounded by an external elastic lamina which functions to anchor vessels with surrounding tissues.
What are the layers of an arterial blood vessel wall?
The blood vessel wall has three layers: intima, media, and adventitia. The intima consists of endothelium and subendothelial connective tissue and is separated from the media by the elastic lamina interna.