Key Differences between Arteries and Veins
The main difference between arteries and veins is that arteries supply oxygenated blood from the heart to all the body parts while veins carry deoxygenated blood from all the body parts towards the heart. The exception to this is only pulmonary artery which carries deoxygenated blood and pulmonary vein which carry oxygenated blood.
There are many differences between arteries and veins. As per definition, arteries transfer, oxygen-rich blood pumped from the heart to the whole body while veins carry oxygen-depleted blood from the whole of the body to the heart. Both arteries and veins are found in the types of organisms which have ‘closed circulatory’ system.
Arterial walls are muscular and elastic. Walls of veins are less elastic. They are easily compressible opposite to arterial walls. Arteries are present deep inside the body while skin is present superficial and close to the skin. They can easily be felt.
The lumen of arteries is narrow while that of veins is broad. Walls of arteries are thick while walls of veins are thin.
Tunica Externa of arteries is less developed and less strong while that of veins is more strong and developed. Tunica Externa is the outermost part of the wall of any vessel. Tunica media (middle part of the vessel) of arteries is more thick and muscular while that of veins is less muscular and thin.
The pressure of blood in the arteries is more while it is less in veins. That is the reason that arteries have thick walls to support high blood pressure while veins have thin walls to support relatively low blood pressure.
Arteries contain almost 30% of the blood volume while veins contain almost 65% of the blood volume.
Pulse can be detected in the arteries while it cannot be detected in the veins.
Valves are not present in the arteries while valves are present in the veins to prevent backflow of blood.
Many diseases can affect the arteries, but the main of them is atherosclerosis. The major disease which affects the veins is deep venous thrombosis.
Due to the high elasticity of the walls of the arteries, they are collapsed if blood flow is stopped while veins remain open even if blood flow is stopped because of the thick muscular wall and less elasticity.
Comparison chart
| Basis | Arteries | Veins |
| Definition | Arteries transfer oxygen-rich blood pumped from the heart to all the body parts. | Veins are the vessels which carry oxygen-poor blood from all the body parts to the heart. |
| Elasticity | Walls of arteries have high elasticity | Walls of veins are less elastic. |
| Compressibility | Due to high elasticity, arteries are easily compressible. | Veins are less elastic, and that is why they are not easily compressible. |
| Location | Arteries are located deep in the body. They cannot be seen directly. | Veins are located superficial in the body and close to the skin. Some veins are visible through the skin. |
| Pulses | Pulses can be felt in arteries. | Pulses cannot be felt in veins. |
| Parenteral injections | Parenteral injections cannot be given through arteries. | Parenteral injections are given through superficial veins. |
| External layer | The external layer is weak and less developed. | The external layer is stronger and more developed. |
| Middle layer | Tunica media is more thick and muscular. | Tunica media is thin than arteries. |
| Blood pressure | The pressure of blood is high in arteries. | The pressure of blood in veins is low as compared to arteries. |
| Thickness | The overall thickness of the arterial wall is more to support high blood pressure. | The overall wall thickness of veins is less to support less blood pressure. |
| Pulmonary artery | Pulmonary arteries contain deoxygenated blood which is carried from the heart to lungs. | Pulmonary veins contain oxygenated blood which is carried from the lungs to the heart. |
| Pulmonary vein | A major disease occurring in arteries is atherosclerosis. | A major disease occurring in veins is deep venous thrombosis. |
| Collapsed walls | Walls of arteries are collapsed if blood flow is stopped in them because of high elasticity. | Walls of veins are not collapsed even if blood flow is stopped because of less elastic content. |
| Valves | Valves are not present in arteries. | Valves are present in some veins to prevent backflow of blood. |
| Amount of blood present | Almost 30% of total blood is present in arteries. | Almost 65% of total blood is present in veins. |
What are arteries?
Arteries are the types of blood vessels which transfer oxygenated blood from the heart to all the parts of the body. Both arteries and veins are found in the organisms which have closed type of circulatory system. A wall of an artery contains three layers, i.e., tunica Externa which is the outermost layer, tunica media which is the middle layer and tunica intima which is the innermost layer. The walls of the arteries are highly elastic and thick to support the high pressure of blood. The blood from the heart is pumped in aorta from where it is supplied to all the body parts by corresponding arteries. The pulmonary artery contains deoxygenated blood because it is the artery through which deoxygenated blood is carried from the heart to the lungs for oxygenation. Arteries contain almost 30% of the total amount of blood. Due to high elasticity, arteries are collapsed if blood flow is stopped. Arteries are placed deep in the body, and they cannot be visualized. Pulses can be felt only in the arteries.
What are veins?
Veins are the types of vessels which carry deoxygenated blood from the heart to all the other body parts. Only the pulmonary vein contains oxygenated blood because it is the vein which carries oxygenated blood from the lungs to the heart. The walls of veins also contain the three layers the same as the arteries, i.e., tunica Externa, tunica media, and tunica intima. The walls of veins are highly muscular and less elastic, and that is why they are not so easily compressible. If the blood flow is stopped, the walls of the veins remain open. Veins contain almost 65% of the blood. Valves are present in the veins of legs to avoid the backflow of blood due to gravity. Veins may be superficial or deep. Superficial veins are usually visible through the skin and injections are given through them. Deep veins cannot be visualized. Pulses cannot be felt in the veins. There are many diseases of the veins, but the most common among all is deep venous thrombosis.
Key Differences between Arteries and Veins
- Arteries transfer oxygen-rich blood from the heart to all the other body parts while veins carry oxygen-depleted blood from the body parts to the heart
- Walls of arteries are highly elastic while walls of veins are less elastic and more muscular.
- Valves are not present in the arteries while present in the veins to avoid backflow of blood.
- If blood flow is stopped, arteries are collapsed while veins are not.
- Arteries have high blood pressure and thick walls while veins have low blood pressure and thin walls.
Conclusion
Arteries and veins are the types of blood vessels found in the animals having closed type of circulatory system. One must know the differences between both of them especially the biology students. In the above article, we learned the clear differences between arteries and veins.