Arteries and veins supply blood to various parts of the body. They are called blood vessels because they distribute blood to various body parts.
These two structures work in synergy but they differ in so many ways. Let us dig deeper into their differences.
Picture 1: Arteries carry oxygenated blood from the heart to various parts of the body.
Image Source: wikimedia.org
They are blood vessels that carry oxygenated blood away from the heart going to different parts of the body. Aside from the blood, they also carry other nutrients from the heart to the different tissues of the body. (1, 2, and 3)
Structures of the artery
The artery is a muscular tube. It is built that way so that it can carry the higher pressure of blood exerted by the heart during its pumping mechanism. It has three layers namely:
- Intima – It is the innermost layer that gets in direct contact with the blood.
- Media – It is the middle layer made up of elastic fiber and smooth muscles.
- Adventitia – It is the outermost layer consists of elastic fiber, collagen, and connective tissues. (3, 4)
The table below shows the three layers of the artery.
|Layers of the artery||Location and components|
|Tunica Intima||Innermost layer/direct contact with the blood|
|Tunica Media||Middle layer/consists of smooth muscles and elastic fiber|
|Tunica Adventitia||Outermost layer/consists of elastic fiber, collagen, connective tissues|
Picture 2: Veins carry deoxygenated blood from various parts of the body going back to the heart.
Image Source: study.com
They are blood vessels that carry low oxygenated blood from the different parts of the body back to the heart.
Structures of the vein
Veins have several layers namely:
- Intima – The innermost layer made up of muscles and soft tissues.
- Media – The thinner layer made up of elastic fiber and smooth muscles.
- Adventitia – The outer covering made up of collagen, elastic fiber, and connective tissues. (3, 4, and 5)
The layers of the vein are summarized in the table below.
|Layers of the veins||Location and components|
|Tunica Intima||Innermost layer consists of muscles and soft tissues|
|Tunica Media||The thinner layer consists of elastic fiber and smooth muscles|
|Tunica Adventitia||The outermost covering made up of elastic fiber, collagen, and connective tissues|
Types of veins
- Deep veins – They are located within the muscle tissues deep in the body. They carry a vast majority of the blood.
- Superficial veins – They are close to the surface of the skin.
- Connecting veins – The blood from the superficial veins is directed to the deep veins with the help of connecting veins.
- Pulmonary veins – They are located in the lungs and each lung has two sets of pulmonary veins. Their primary function is to transport oxygenated blood from the lungs to the heart.
- Systemic veins – They are all over the body and their role is to transport deoxygenated blood back to the heart. (4, 5, and 6)
|Type of vein||Location||Functions|
|Deep veins||Within the muscles|
Deep in the body
|Carry the vast majority of the blood|
|Superficial veins||Close to the surface of the skin||They are not as important as the deep vein. They carry less blood. In some cases, they are stripped to treat varicose veins.|
|Connecting veins||In between the superficial vein and deep vein||Serves as a junction or connection for the superficial vein and deep vein|
|Pulmonary veins||Located in the lungs||They transport oxygenated blood from the lungs to the heart.|
|Systemic veins||Found all over the body||They transfer deoxygenated blood back to the heart.|
What are the similarities of veins and arteries?
- They are both blood vessels which are vital in the circulatory system.
- They both carry blood and other nutrients.
- They are both consist of three layers. (5, 6)
Picture 3: A comparison image between veins and arteries.
Image Source: ytimg.com
Picture 4: A comparison image between veins and arteries.
Image Source: skinandvein.com
Picture 5: A comparison image between a normal artery and atherosclerotic artery.
Image Source: cdc.gov
For the detailed differences between veins and artery refer to the table below.
|Points of comparison||Arteries||Veins|
|Circulatory route||Carry blood from the heart to different parts of the body||Carry blood from the different parts of the body to the heart|
|Type of blood||Oxygenated blood except for the pulmonary artery||Deoxygenated blood except for the pulmonary vein|
|Location||Deep within the body||Closer to the surface of the skin(7)|
|Valves||Arteries have valves||Veins do not have valves|
|Blood Pressure||High pressure is needed for the blood to flow through||Low pressure is enough for the blood to flow through|
|Ability to detect pulse||Palpation of the artery will help detect pulse||Pulse is not detectable|
|Lumen diameter||Narrow but changes depending on the beating of the heart(5, 6)||Wide|
|Movement of blood||Spurty||Sluggish|
|Carbon dioxide level||Low||High|
|Blood flow pathway||Distinct||Indistinguishable because veins have many interconnections|
|What happens if the flow of blood is stopped?||The artery will still remain open||The vein will collapse right away|
|Time of death||The artery empties up at the time of death||The veins are filled up at the time of death|
Arteries and veins have similarities and differences. One thing is for sure though, they are vital parts of the circulatory system. These two structures are responsible for carrying blood to different parts of the body. The arteries carry oxygenated blood from the heart to different parts of the body with the exception of pulmonary artery.
On the other hand, deoxygenated blood is carried out by the veins from various parts of the body to the heart where it will be supplied with oxygen with the exception of the pulmonary veins. The process goes on and on.
The heart, arteries, and veins are the three essential components of the circulatory system. Any problems in the veins and arteries can significantly affect the circulatory system. Which is why it is important to maintain a healthy lifestyle to prevent circulatory problems. (1, 6, and 9)
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