Arteries vs Veins
Similarities and Differences between Arteries and Veins
The circulatory system in an organism ensures the transport of oxygen, nutrients, carbon dioxide and hormone throughout the body. The blood circulatory system in an animal is facilitated by the heart (the blood pumping organ) and blood vessels (closed pipelines which carry out the circulation of blood throughout the body). There are three types of blood vessels in our body. They are:
(1). Artery: They are blood vessels which originated from the heart and carry blood away from the heart. Arteries usually carry oxygenated blood except for pulmonary and umbilical arteries that carries deoxygenated blood.
(2). Vein: They are blood vessels which carry blood to the heart from various organs of the body. Veins usually carry deoxygenated blood except for pulmonary and umbilical vein that carries oxygenated blood.
(3). Capillaries: They are minutes blood vessels of one cell layer thickness and they facilitate the exchange of oxygen, carbon dioxide, nutrients and hormones in the blood to individuals cells of different organs. Arteries and veins are interconnected through capillaries and thus the blood circulation forms a closed system in majority of animals.
The current post describes the similarities and differences between Arteries and Veins with a comparison table.
Similarities between Arteries and Veins
Ø Both are blood vessels.
Ø Both transport blood.
Ø Blood transport is unidirectional in both arteries and vein.
Ø Arteries and veins composed of layers of cells.
Ø Both arteries and veins composed of three layers of cells namely Tunica externa (external layer), tunica media (middle layer) and tunica interna (internal layer).
Ø Both arteries and veins are covered by muscular tissues which assist in the contraction or expansion of blood vessels.
Ø Both undergo vasoconstriction and vasodilation to adjust the blood pressure according to the action of hormones and neurotransmitters.
Ø Both arteries and veins show anastomosis.
Difference between Arteries and Veins
Sl. No. Artery Vein 1 Carry blood away from the heart Carry blood towards the heart 2 Carry oxygenated blood Carry deoxygenated blood 3 Pulmonary artery carry deoxygenated blood Pulmonary vein carry oxygenated blood 4 Red in colour due to oxygenated bold they carry Veins are blue in colour, since they carry deoxygenated blood 5 Usually located deep in the body Usually located close to the skin 6 Artery is a resistance blood vessel Vein is a capacitance blood vessel 7 Middle layer of artery (tunica media) is thick Tunica media relatively thin in veins 8 Tunica media composed of elastic and smooth muscle tissues Tunica media composed of few elastic fibres and it is less muscular 9 Wall of artery is elastic Wall of vein is not elastic 10 Semilunar valves absent (except where the artery leaves the heart) Semilunar valves present at regular intervals to prevent the backflow of blood 11 Arteries possess narrow lumen Veins possess wide lumen 12 Pressure of blood flowing through the artery is high Pressure is low 13 Pulse is detectable in the artery Pulse not detectable in the vein 14 Blood flow rate is quick and rapid Blood flow rate is slow and steady 15 Blood volume is low Much higher blood volume than capillaries and arteries 16 Carry about 30% of the systemic circulation of blood in human Carry about 65% of the systemic circulation of blood in human
*the rest 5% is in blood capillaries
17 Arteries are emptied up at the time of death Veins are filled up at the time of death 18 Atherosclerosis is the main disease affecting the arteries Deep vein thrombosis is the main disease affecting the veins