The cardiovascular system contains the heart and blood vessels with loaded of blood. Blood vessels are parted into arterioles, arteries, capillaries and veins. Arteries bring blood from the heart to the tissues, and are altered into arterioles, which are come apart into a system of very thin vessels, capillaries. Now from the capillaries start small veins, they combine together and turn out to be stronger.
Cardiovascular System Functions
Cardiovascular system works to carry blood required to carry out its carrying functions and the functions are to carry the blood to the tissues of
nutrients and oxygen and eliminating metabolic produce and carbon dioxide. In the core of the circulatory system is heart of it originates big and small flow.
Systemic flow starts large artery-aorta and it splits the large number of medium-sized arteries and these for numerous of small arteries. The end in turn divides into many capillaries. The wall of the capillaries has a great permeability, allowing the switch of substances between blood and tissues: nutritional, and oxygen go by through the wall of capillaries in tissue fluid and after that into the cells, in turn, provide the cells in the tissue fluid carbon dioxide and additional metabolic products that appear in the capillaries.
Arteries are blood vessels that take away blood from the heart and this blood is usually oxygenated, while there is some exceptions in case of the pulmonary and umbilical arteries. Arteries are stretchy tubes of dissimilar calibers. The wall of the arteries contains three layers which are outer, middle and inner. The outer wall is created by connective tissue; the middle contains smooth muscle cells and elastic fibers. And the inner wall contains the vessel from the inside and enclosed by endothelium.
Veins are blood vessels that take blood towards the heart. The majority of veins transmit deoxygenated blood from the tissues rear to the heart. Veins have the similar construction with the arteries; however their walls are much thinner than arteries, may subside. In the lower part of body the veins muscular since these had to rise above the force of gravity and have to take the blood opposed to the gravity. The inner wall of veins forms folds in the valves, which are set in pairs at usual intervals and stop the back flow of blood.