The blood vessels include three major divisions arteries deliver blood from heart to capillaries Capillaries the smallest blood vessels and closest to body cells, the interchanges between blood and tissues occur there Veins carry blood from body to the heart
The blood vessels include three major divisions: Arteries – deliver blood from heart to capillaries Capillaries – the smallest blood vessels and closest to body cells, the interchanges between blood and tissues occur there Veins – carry blood from body to the heart
Histological Structure of Blood vessels Tunica LARGE VEIN n ELASTIC ARTERY Internal elastic externa intima Endothelium Tu Tunica externa Tunica intima Endothelium MUSCULAR ARTERY MEDIUM-SIZED VEIN Tunica Tunica externa Tunica media Tunica intima Tunica intima Endothelium ARTERIOLE VENULE Smooth muscle cells Tu Endotheliul externa Basal lamina Endothelium CONTINUOUS CAPILLARY FENESTRATED CAPILLARY △ Endothelial cells Endothelial cells Basal lamina Basal lamina
Histological Structure of Blood Vessels
Structural feature of Internal elastic lamina Endothelium Arteries andⅤeins Intima Media Tunica intimae 1. Endothelium 2. Subendothelial layer 3. Internal elastic membrane Adventitia nica eala medium-sized a Mainly smooth muscle Tunica adventitia external elastic membrane Mainly connective tissue
Structural feature of Arteries and Veins: Tunica intimae 1. Endothelium 2. Subendothelial layer 3. Internal elastic membrane Tunica media Mainly smooth muscle Tunica adventitia external elastic membrane Mainly connective tissue medium-sized A
Artery transport blood from heart to capillaries according to their size, structure and function Large artery Medium-sized artery d>lmm are classified Small artery d>0.3-1mm Arteriole d<o 3mm
Artery ▪ transport blood from heart to capillaries ▪ according to their size, structure and function Large artery Medium-sized artery D>1mm Small artery D>0.3~1mm Arteriole D<0.3mm are classified
Structure features of artery The wall of arteries consist of three layers or"coats' often referred to as tunics bundles elastie fibers ur nerve biood vess Tunica intimae-is the inner coat Tunica media-is the middle layer Tunica adventitia or tunica externa is the outer layer of the wall of the blood vesse Layers of arteries wall differ in MUSCULAR ARTERY different size blood vessels The structure and function of arteries change as their diameter decreases
• The wall of Arteries consist of three layers or “coats” often referred to as tunics. – Tunica intimae – is the inner coat – Tunica media – is the middle layer – Tunica adventitia or tunica externa is the outer layer of the wall of the blood vessel • Layers of arteries wall differ in different size blood vessels. The structure and function of arteries change as their diameter decreases. Structure features of artery