15 Important Differences Between Arteries and Veins

Arteries and Veins

Arteries and veins are two types of blood vessels that are responsible for circulating blood throughout the body. They are both part of the circulatory system and share some similarities, they also have several key differences that are important to understand.

Arteries are blood vessels that carry oxygen-rich blood away from the heart and to the body’s tissues. They are thick-walled, muscular and elastic. Arteries  have a pulse that can be felt at various points in the body. 

Veins are blood vessels that carry oxygen-poor blood back to the heart from the body’s tissues. They have thinner walls, less muscle and elasticity and have valves that prevent blood from flowing backward.

Differences Between Arteries and Veins – Table format

Differences Between Arteries and Veins in tabular format is as follows –

	Characteristics	Arteries	Veins
1.	Definition	Blood vessels which carry blood away from the heart and into an organ.	Blood vessels which carry blood away  from an organ and towards  the heart, (Except hepatic portal vein)
2.	Structure	Progressively branched,                           decreasing in size. Smallest artery   breaks into arterioles.	Progressively unite increasing in size.Smallest vein arises from venules.
3.	Blood	Arteries carry fully oxygenated blood (except pulmonary artery) and   nutrients.	Veins carry deoxygenated blood       (except pulmonary vein) rich in  Waste materials.
4.	Location	They are deeply situated within the body. They do not collapse when there is no blood in it.	They are superficial peripherally located closer to the skin. They collapse when there is no blood in it or cut across
5.	Walls	Artery walls are rigid, thicker and highly muscular. Walls are elastic.	Veins walls are thin and collapsible walls. Walls are non-elastic
6.	Division	Arteries are further divided into       arterioles.	Veins are further divided into                  venules
7.	Lumen	Have narrower lumen	Have wider lumen.
8.	Color	Arteries are red in color.	Veins are blue in color.
9.	Blood Flow	Can constrict or dilate to control blood flow.	Can not constrict
10.	The direction of blood flow	Arteries carry blood away from the heart to various parts of the body.	Veins carry blood from the various parts of the body towards the heart.
11.	Flow pressure	The pressure is high as the blood flows by the pumping pressure of the heart.  Blood flows with jerks  and under great pressure.	Pressure is low as the blood flows by the capillary action of the veins.          Blood flows continuously  and under very little pressure
12.	Oxygen level	These oxygen levels are quite high in the arterial blood.	Oxygen level is comparatively low.
13.	Carbon dioxide level	The level of the carbon dioxide is low in the arterial blood.	The level of the carbon dioxide is high in the Venous blood.
14.	Valves	Have no valves in their inner  lining.	Have valves in their inner lining to      prevent backward flow of blood
15.	Injury	If an arterial wall is injured, the blood comes out like a fountain in a large area all around the artery.	If the venous wall is injured,blood comes out, collects in a pool in a small area  around the vein.

Also Check – Why Do Arteries Have Thick Elastic Walls ?

Also Check – Arteries in The Body

Differences Between Arteries and Veins – Explained in Details

Differences between Arteries and Veins  in terms of Definition

Arteries are blood vessels that carry oxygenated blood from the heart to the body’s tissues and organs. Veins are blood vessels that carry deoxygenated blood from the body’s tissues and organs back to the heart.

Differences between Arteries and Veins  in terms of Blood

Arteries carry oxygenated blood away from the heart and towards the body’s tissues and organs. The blood in arteries is under high pressure and flows rapidly due to the pumping action of the heart. In contrast, veins carry deoxygenated blood back to the heart from the body’s tissues and organs. The blood in veins is under low pressure and flows slowly.

Differences between Arteries and Veins  in terms of Location

Arteries are typically located deeper within the body and are closer to the bone. Veins are located closer to the surface of the body and are more visible under the skin.

Differences between Arteries and Veins  in terms of Walls

Arteries have thick walls made up of three layers – the intima, media and adventitia. The intima is the innermost layer and is made up of endothelial cells, which provide a smooth surface for blood flow. The media is the middle layer and is composed of smooth muscle cells that help regulate blood pressure by contracting and relaxing. The adventitia is the outermost layer and is made up of connective tissue that supports and protects the artery.

Veins, on the other hand, have thinner walls than arteries and only two layers – the intima and adventitia. The media layer is usually thin or absent in veins. The walls of veins also contain valves that prevent the backflow of blood.

Differences between Arteries and Veins  in terms of Division

Arteries divide into smaller arterioles, which further divide into capillaries. Capillaries are the smallest blood vessels in the body and allow for the exchange of nutrients and gasses between the blood and surrounding tissues. Veins, on the other hand, begin as small venules, which merge to form larger veins.

Lumen

The lumen is the central space within a blood vessel where blood flows. Arteries have a smaller lumen compared to veins due to their thicker walls. Veins have a larger lumen and thinner walls, which allows them to hold more blood.

Differences between Arteries and Veins  in terms of Color

Arteries appear bright red in color due to the high oxygen content of the blood they carry. Veins, on the other hand, appear darker in color due to the lower oxygen content of the blood they carry.

Differences between Arteries and Veins  in terms of Blood Flow

Arteries carry oxygen-rich blood away from the heart to the body’s tissues. Veins, on the other hand, carry oxygen-depleted blood back to the heart. The flow of blood in arteries is pulsatile and is due to the pumping action of the heart. In contrast, the flow of blood in veins is steady and is assisted by the contraction of surrounding muscles.

Differences between Arteries and Veins  in terms of Carbon Dioxide Level

Arteries and veins differ in their carbon dioxide (CO2) level because of the direction of blood flow. Arteries carry oxygenated blood away from the heart and towards the body’s tissues, while veins carry deoxygenated blood back to the heart. This means that arteries typically have a higher concentration of oxygen and a lower concentration of carbon dioxide, while veins have a higher concentration of carbon dioxide and a lower concentration of oxygen. However, there are exceptions to this general pattern, such as in the pulmonary arteries and veins, where oxygen and carbon dioxide levels are reversed due to their location in the lungs.

Differences between Arteries and Veins  in terms of Valve

Valves are structures in veins that help prevent the backflow of blood. Veins have valves while arteries do not. The valves in veins work by opening in one direction, allowing blood to flow towards the heart and closing in the opposite direction to prevent the backflow of blood. This is especially important in the legs where blood must flow upwards against gravity.

Differences between Arteries and Veins  in terms of Injury

Arteries and veins also differ in their response to injury. Arteries are more prone to damage because of their thick muscular walls, which make them more susceptible to high blood pressure and atherosclerosis (buildup of plaque in the arterial walls). When an artery is injured, it can lead to bleeding, thrombosis (clotting) and blockages. Veins, on the other hand, are less prone to injury and can often repair themselves more easily. However, when veins are injured, they can lead to the formation of blood clots or varicose veins.

Differences between Arteries and Veins  in terms of Direction of Blood Flow

Arteries and veins differ in the direction of blood flow. Arteries carry blood away from the heart, while veins carry blood towards the heart. This is because the heart pumps blood out through the arteries to supply oxygen and nutrients to the body’s tissues and the veins bring the blood back to the heart to be oxygenated again.

Differences between Arteries and Veins  in terms of Flow Pressure

Arteries and veins differ in their flow pressure. Arteries have a higher pressure than veins because they need to pump blood further and against the force of gravity. Arteries have thick, elastic walls that allow them to withstand the high pressure and maintain a constant flow of blood to the body’s tissues. In contrast, veins have thinner walls and less elastic tissue, allowing them to expand and contract to accommodate changes in blood flow.

Differences between Arteries and Veins  in terms of Oxygen Level

Arteries and veins also differ in their oxygen level. Arteries carry oxygen-rich blood, while veins carry oxygen-poor blood. This is because the oxygen-rich blood is pumped out of the heart through the arteries to supply oxygen and nutrients to the body’s tissues. As the tissues use up oxygen, the blood becomes oxygen-poor and is returned to the heart through the veins. The exception to this is the pulmonary artery and vein, which carry oxygen-poor and oxygen-rich blood respectively, due to their location in the lungs where oxygen is exchanged between air and blood.

Also Check – 7 Structural and Functional Difference Between Arteries, Veins and Capillaries