tofe_E
04-30-2007, 08:25 PM
THE CARDIO VASCULAR system
the cardio vascular system composed of two circuits
1-the pulmonery circut2-the systemic circuit
the cardio vascular system is composed of the heart
which is amscular organ that pumps the blood in to circuit:1-the pulmonery circuit which carries blood to and from
the lungs.2-systematic circuit which distributes blood to and from all organs and tissue of the body.
Vessels:1-artery2-vein 3-cappilaries
the artery or vein composed of three layers:1-tunica intima(T.intima)2-tunica media(T.media)3-tunica adventitia(T.adventitia)
[
T. intima]
The t.intima is composed of a simple squamous epithelium and subendothelial connective tissue.
The endotheial cells (simple squamous epithelium)
Lining the lumen of the blood vessel rest on a basal lamina .these flattened cells are elongatedin to sheets such that their long axis is more or less parallel to the long axis of vessel.
Asub endo theilal layer lies immediately beneath the endo thelial cells. It is composed of loose connective tissue and few scattered smooth muscle cells both arrange longitudinally.
Beneath the sub endothelial layer is an elastic lamina that is especially well developed in muscular arteries.
Separating the T.intima from the T.media the internal elastic lamina. Is composed of elastin.
[
T.media]
the T.media usually the thickest layer of the vessels wall it composed of helically diposed layers of smooth muscle.
The T.media is the thickest of vessel. The concentric cell layers forming the T.media comprise mostly helically arranged smooth muscle cells. inter seperesed with in the layers of smooth muscle are some elastic fibers type III collagen and proteoglycans.
Large muscle artereis have an external elastic lamina which is more delicate than the internal elastic lamina and separates the T .media from the over laying T.adventitia.
Cappillaries and post capillary venules do not have a T.media in these small vessels pericytes replace the T.media .
[
T.advantitia]
the T.advantitia is the outer layer of the vessel wall blends into the surrounding connective tissue.
T.advantitia covering the vessels on their outside surface composed mostly of fibroblasts type I collagen fibers and longitudinally oriented elastic fibers.
The layer become continuous with the connective tissue elements surrounding the vessels.
svasa vasorum
vasa vasorum furnish the muscular walls of blood vessels with a blood supply.
Classification of arteries
Artery is divided in to three major type according to size and morphological characteristics or both :1-large artery (elastic artery) such as aorta2-median size artery(muscular artery)
small size artery (muscular artery)3-arterioles
-Elastic arteries
concentric layer of elastic membranes known as fenestrated membranes occupy much of the T.media. the aorta and the branches originating from:
1-the aortic arch (the common carotid artery and sub clavian artery)
2-the common iliac arteries
-the pulmonary turnk are elastic arteries
the wall of these vessels may be yellow in fresh state because of the abundance of elastin .
the T.intima of the elastic arteries is composed of an endothelium that is supported by narrow layer of underlying connective tissue contains afew fibro blasts. Occasional smooth muscle cells and collagen fibers .the inter elastic lamina are also present.
The endothelial cells of the elastic arteries are 10-15 micro meter wide and 25-50micro meter long……. their long axis are oriented parallel to the longitudinal axis of the vessel.
Their plasma membranes contain small vesicles thought to be related to transport of water …macro molecules and electrolytes occasional blunt processes may extend from the plasma membrane
مع تحياتي مصطفى عماد
tofe_e@yahoo.com
the cardio vascular system composed of two circuits
1-the pulmonery circut2-the systemic circuit
the cardio vascular system is composed of the heart
which is amscular organ that pumps the blood in to circuit:1-the pulmonery circuit which carries blood to and from
the lungs.2-systematic circuit which distributes blood to and from all organs and tissue of the body.
Vessels:1-artery2-vein 3-cappilaries
the artery or vein composed of three layers:1-tunica intima(T.intima)2-tunica media(T.media)3-tunica adventitia(T.adventitia)
[
T. intima]
The t.intima is composed of a simple squamous epithelium and subendothelial connective tissue.
The endotheial cells (simple squamous epithelium)
Lining the lumen of the blood vessel rest on a basal lamina .these flattened cells are elongatedin to sheets such that their long axis is more or less parallel to the long axis of vessel.
Asub endo theilal layer lies immediately beneath the endo thelial cells. It is composed of loose connective tissue and few scattered smooth muscle cells both arrange longitudinally.
Beneath the sub endothelial layer is an elastic lamina that is especially well developed in muscular arteries.
Separating the T.intima from the T.media the internal elastic lamina. Is composed of elastin.
[
T.media]
the T.media usually the thickest layer of the vessels wall it composed of helically diposed layers of smooth muscle.
The T.media is the thickest of vessel. The concentric cell layers forming the T.media comprise mostly helically arranged smooth muscle cells. inter seperesed with in the layers of smooth muscle are some elastic fibers type III collagen and proteoglycans.
Large muscle artereis have an external elastic lamina which is more delicate than the internal elastic lamina and separates the T .media from the over laying T.adventitia.
Cappillaries and post capillary venules do not have a T.media in these small vessels pericytes replace the T.media .
[
T.advantitia]
the T.advantitia is the outer layer of the vessel wall blends into the surrounding connective tissue.
T.advantitia covering the vessels on their outside surface composed mostly of fibroblasts type I collagen fibers and longitudinally oriented elastic fibers.
The layer become continuous with the connective tissue elements surrounding the vessels.
svasa vasorum
vasa vasorum furnish the muscular walls of blood vessels with a blood supply.
Classification of arteries
Artery is divided in to three major type according to size and morphological characteristics or both :1-large artery (elastic artery) such as aorta2-median size artery(muscular artery)
small size artery (muscular artery)3-arterioles
-Elastic arteries
concentric layer of elastic membranes known as fenestrated membranes occupy much of the T.media. the aorta and the branches originating from:
1-the aortic arch (the common carotid artery and sub clavian artery)
2-the common iliac arteries
-the pulmonary turnk are elastic arteries
the wall of these vessels may be yellow in fresh state because of the abundance of elastin .
the T.intima of the elastic arteries is composed of an endothelium that is supported by narrow layer of underlying connective tissue contains afew fibro blasts. Occasional smooth muscle cells and collagen fibers .the inter elastic lamina are also present.
The endothelial cells of the elastic arteries are 10-15 micro meter wide and 25-50micro meter long……. their long axis are oriented parallel to the longitudinal axis of the vessel.
Their plasma membranes contain small vesicles thought to be related to transport of water …macro molecules and electrolytes occasional blunt processes may extend from the plasma membrane
مع تحياتي مصطفى عماد
tofe_e@yahoo.com