For most of us, it is a little difficult to know the difference between arteries and veins. Some of the blood vessels carry blood away from the heart and there are other blood vessels that carry blood back to the heart. So which one is arteries and which one is veins? Today, we will learn about it. So without much ado, let us begin our article on difference between veins and arteries.
What is the Blood Circulatory System?
Circulatory system is also known as the cardiovascular system. It consists of blood vessels and heart. This system helps in supplying hormones, oxygen and nutrients to the cells and take away carbon dioxide and waste products from the cells. Heart and blood vessels circulate blood throughout your body.
The Three Major Types of Blood Vessels: Arteries, Veins, and Capillaries
There are three kinds of blood vessels i.e. arteries, veins, and capillaries.
Arteries transport oxygenated blood away from the heart from the cells.
Veins carry deoxygenated blood to the heart to the cells.
Capillaries are the blood vessels that connect arteries and veins. They are the smallest blood vessels in our body.
What are Arteries?
As mentioned earlier, arteries are the blood vessels that carry oxygen-rich blood to the organs from the heart. They also carry hormones and nutrients. The arteries are located deeply in the body. They have thick walls. Valves are absent in arteries. The blood moves with pressure. Arterioles are small branches of arteries. Though muscular, they can get smaller or bigger to maintain blood pressure. Did you know doctors listen to the flow of blood in your arteries to read the pulse of the heart?
What are Veins?
Veins are the blood vessels that carry oxygen-depleted blood from the tissues and cells to the heart. They are both superficially and deeply located in our body and some of the veins are easily visible to the naked eye. As they carry deoxygenated blood, the veins appear blue. They have thin walls. Unlike arteries, veins have valves. Valves prevent blood from flowing backward. It prevents blood from pooling to the legs because of gravity. Veins branch out to smaller blood vessels called venules. Venules increase in their size as they near the heart.
What Are Capillaries?
Capillaries are thin walled blood vessels that connect arteries and veins. It is at the capillaries that exchange of oxygen and carbon dioxide takes place. Capillaries receive oxygen-rich blood from arteries and deliver low-oxygen blood to veins.
Anatomy of Blood Vessels
Arteries and veins are two main types of blood vessels. Both of them have the same layers which are as follows:
Tunica Intima: Also known as tunica interna. It is the innermost layer. It helps in regulation the pressure of the blood and prevents blood clots. It keeps the blood flowing smoothly.
Tunica Media: This layer of a blood vessel is made up of smooth muscle. It is the thickest layer in case of arteries. It provides support and regulates flow of the blood and blood pressure by changing the diameter of the vessel.
Tunica Adventitia: Also known as tunica externa. It consists of elastic and collagen fibers. It is thickest in case of veins.
Types of arteries and veins
Arteries and veins are a part of two closed system of vessels described as follows:
- Pulmonary: Pulmonary arteries are division of arteries that transport low-oxygen blood from heart to lungs and pulmonary vein supplies oxygen-rich blood from lungs to heart.
- Systemic: Systemic arteries are the arteries that carry oxygenated blood from the heart and systemic veins are the veins that carry blood from parts of the body to the heart.
There are three types of arteries
- Elastic: They originate from the heart. They have a thick and elastic middle layer which stretches to adjust blood pressure.
- Muscular: Muscular arteries draw blood from elastic arteries and have medium size. They eventually empty the blood into arterioles.
- Arterioles: They are known as resistance vessels. Arterioles are the smallest blood vessels in the body.
There are four types of veins.
- Deep: They are deeply situated in our body.
- Superficial: They are located near our skin surface.
- Pulmonary: They carry pure and clean blood from the lungs to the heart. All veins transport deoxygenated blood except these type of veins.
- Systemic: They carry impure blood from cells to the heart.
Diseases of Arteries and Veins
Some of the common artery diseases are as follows:
- Aortic aneurysm: It is a balloon like bulge in aorta which may dissect or rupture.
- Coronary heart disease: The arteries fail to supply blood to the heart due to cholesterol or plaque deposits.
- Renal vascular disease: These are a set of conditions that impair the blood flow into the kidneys or out from the kidneys.
Some of the common vein diseases are as follows:
- Varicose veins: Superficial veins can get twisted and engorged and are known as varicose veins.
- Superficial thrombophlebitis: A blood clot is formed in superficial vein It is less serious than DVT.
- Deep vein thrombosis (DVT): A clot forms in your deep veins and may travel up to your lungs and cause pulmonary embolism.
Veins and Arteries: Differences
Arteries carry oxygenated blood to your cells. Veins carry impure blood to your heart.
| Characteristic | Arteries | Veins |
| Outlook | Arteries carry oxygenated blood to your cells. | Veins carry impure blood to your heart. |
| Walls | Arteries are thinner | Veins are thinner |
| Elasticity | Less elastic | More elastic |
| Direction of blood flow | Transport blood away from the heart | Transport blood towards the heart |
| Location | Deeper in the body | Both deep and superficial in the body |
| Pressure | Moves with more pressure | Moves with less pressure |
| Condition at death | Gets emptied at the time of death | Gets stuffed up at the time of death |
| Color | Red | Blue |
| Thickest layer | Tunica Media | Tunica Adventitia |
| Valves | Absent | Present |
| Capacity | Can hold less blood | Can hold more blood |
| Diseases | Peripheral Artery Disease, Renal Vascular Disease, Coronary Artery Disease, | Excessive blood clotting, Spider veins, Phlebitis |
Similarities
Both the blood vessels help in regulating blood flow and distribute blood to the body and heart. Both of them have same layers. They both transport blood in a single direction either towards the heart or away from the heart.
Prevention: How to Promote Healthy Cardiovascular System
To keep your blood vessels and heart healthy, follow these tips.
- Eat a balanced diet. Cut down on junk food and foods containing high level of sodium, cholesterol, etc.
- Quit smoking
- Limit alcohol usage
- Exercise regularly but don’t push it too much.
- Practice yoga and meditation. According to John Hopkins Medicine, yoga improves your overall heart health.