What venous blood. The main differences between venous blood and arterial blood

There's so much you can't find on the net. Even the question about the color of blood and veins is often accompanied by assumptions and fiction, although most people actually know the answer. Yes, everything is simple here - the blood is red, only in different shades, depending on the amount of hemoglobin in it and oxygen enrichment. Everything is as taught in biology and BJD at school: arterial blood(oxygen-rich, coming from the heart) bright scarlet color, A venous(giving oxygen to the organs, returning to the heart) – dark red(burgundy). The veins that are visible under the skin are also red when blood flows through them inside. After all, on their own blood vessels quite transparent. But still, many people have questions such as “Why does blood happen? different color and what does this depend on? and “Why are veins blue or cyan?”

The red color of blood can have different shades. Oxygen carriers, i.e. red blood cells blood cells), have a shade of red depending on hemoglobin - an iron-containing protein found in them that can bind to oxygen and carbon dioxide to transfer them to Right place. The more oxygen molecules connected to hemoglobin, the brighter the red color the blood is. That’s why arterial blood, which has just been enriched with oxygen, is so bright red. After the release of oxygen to the cells of the body, the color of the blood changes to dark red (burgundy) - such blood is called venous.

Of course, the blood contains other cells besides red blood cells. These are also leukocytes (white blood cells) and platelets. But they're not like that significant amount compared to red blood cells to affect the color of blood.

Blood color in anemia and cyanosis

In fact, of course, although the veins carry dark burgundy blood, unlike the bright scarlet arterial blood, they are not at all blue in color. They are red, like the color of the blood that flows through them. And you shouldn’t believe in the theory that you can find on the Internet that the blood actually runs through the vessels is blue, but when cut and in contact with air it instantly turns red - this is not so. Blood is always red, and why is described above in the article.

The veins only appear blue to us. This is explained by the laws of physics about the reflection of light and our perception. When a beam of light hits the body, the skin reflects some of all the waves and therefore looks light, well, or different, depending on melanin. But it transmits the blue spectrum worse than red. But the vein itself, or rather the blood, absorbs light of all wavelengths (but less, in the red part of the spectrum). That is, it turns out that the skin gives us for visibility Blue colour, and the vein itself is red. But, interestingly, the vein actually reflects even a little more red than the skin in the blue spectrum of light. But why then do we see veins blue or cyan? And the reason, in fact, lies in our perception - the brain compares the color of the blood vessel against the bright and warm tone of the skin, and in the end shows us blue.

Why don’t we see other vessels through which blood flows?

If a blood vessel is located closer than 0.5 mm to the surface of the skin, then it generally absorbs almost all blue light, and reflects much more red - the skin looks healthy pink (ruddy). If the vessel is much deeper than 0.5 mm, then it is simply not visible, because the light does not reach it. Therefore, it turns out that we see veins that are approximately located at a distance of 0.5 mm from the surface of the skin, and why they are blue has already been described above.

Why can't we see arteries from under the skin?

In fact, about two-thirds of the blood volume is in the veins at all times, therefore they bigger size than other vessels. In addition, arteries have much thicker walls than veins, because they have to withstand more pressure, which also prevents them from being sufficiently transparent. But even if the arteries were visible from under the skin as well as some veins, it is assumed that they would have approximately the same color, despite the fact that the blood running through them is brighter.

What color are veins actually?

If you've ever cooked meat, you probably already know the answer to this question. Empty blood vessels are reddish-brown in color. There is not much difference in color between arteries and veins. They differ mainly when viewed in cross section. Arteries are thick-walled and muscular, while veins have thin walls.

As for aristocrats, the expression “ blue bloods" appeared due to the pallor of their skin. Until the twentieth century, tanning was not in fashion, and the aristocrats themselves, especially women, hid from the sun, thereby protecting their skin from premature aging and looked appropriate to their status, that is, they differed from the serfs who “plowed” all day in the sun. Now we understand that pale color skin with a blue tint is actually a sign of less health.

But scientists also claim that there are about 7,000 people in the world whose blood has a blue tint. They are called kyanetics (from the Latin cyanea - blue). The reason for this is not the same hemoglobin. Their protein contains more copper than iron, which during oxidation acquires a blue tint instead of the red we are accustomed to. These people are considered more resistant to many diseases and even injuries, as their blood is said to clot several times faster and are not susceptible to many infections. In addition, there are different theories about the origin of kianeticians, including that they are descendants of aliens. There is not much information about them on the Internet, but there are articles in foreign publications where the birth of such children is explained by the abuse of rudimentary drugs long before conception. As they say, “Don’t smoke, girl, the children will be green!”, but the results from birth control may turn out blue (meaning the color of blood).

Blood performs in the body main function– provides organs with tissues with oxygen and other nutrients.

It takes carbon dioxide and other decay products from the cells. Thanks to this, gas exchange occurs, and the human body functions normally.

There are three types of blood that constantly circulate throughout the body. These are arterial (A.K.), venous (V.C.) and capillary fluid.

What is arterial blood?

Most people think that arterial view flows through the arteries, and venous flows through the veins. This is an erroneous judgment. It is based on the fact that the name of blood is associated with the name of blood vessels.

The system through which the fluid circulates is closed: veins, arteries, capillaries. It consists of two circles: large and small. This contributes to the division into venous and arterial categories.

Arterial blood enriches cells with oxygen (O 2). It is also called oxygenated. This blood mass from the left ventricle of the heart is pushed into the aorta and flows through the arteries of the systemic circle.

Having saturated the cells and tissues with O 2, it becomes venous, entering the veins of the systemic circle. In the pulmonary circulation, the arterial mass moves through the veins.

Some arteries are located deep in the human body and cannot be seen. The other part is located close to the surface of the skin: the radial or carotid artery. In these places you can feel the pulse. Read from which side.

How is venous blood different from arterial blood?

The movement of this blood mass occurs in a completely different way. The pulmonary circulation begins from the right ventricle of the heart. From here, venous blood flows through the arteries to the lungs.

More information about venous blood -.

There it gives off carbon dioxide and is saturated with oxygen, turning into an arterial type. The pulmonary vein returns blood to the heart.

In the large circulatory system, arterial blood flows from the heart through the arteries. Then it turns into V.K., and through the veins it enters the right ventricle of the heart.

The venous system is more extensive than the arterial system. The vessels through which blood flows are also different. So the vein has more thin walls, and the blood mass in them is slightly warmer.

Blood in the heart does not mix. Arterial fluid is always in the left ventricle, and venous fluid is always in the right.

Differences between the two types of blood

Venous blood is different from arterial blood. The difference lies in the chemical composition of the blood, shades, functions, etc.

The arterial mass is bright red. This is explained by the fact that it is saturated with hemoglobin, which has added O 2. For V.K. Characteristic is a dark burgundy color, sometimes with a bluish tint. This suggests that it contains a high percentage of carbon dioxide.
According to biology research chemical composition A.K. rich in oxygen. Average percentage of O 2 content healthy person– over 80 mmhg. IN VK. the indicator drops sharply to 38 – 41 mmhg. The carbon dioxide indicator is different. In A.K. it is 35 - 45 units, and in V.K. the proportion of CO 2 ranges from 50 to 55 mmhg.

Not only oxygen, but also useful microelements enter the cells from the arteries. In the venous - large percentage products of breakdown and metabolism.

The main function of A.K. – provide human organs with oxygen and nutrients. VC. necessary in order to deliver carbon dioxide to the lungs for further removal from the body and to eliminate other breakdown products.

In addition to CO 2 and metabolic elements, venous blood also contains useful substances that absorb digestive organs. The blood fluid also contains hormones secreted by the endocrine glands.

Blood through the arteries big ring blood circulation and the small ring moves with at different speeds. A.K. ejected from the left ventricle into the aorta. It branches into arteries and more small vessels. Next, the blood mass enters the capillaries, feeding the entire periphery with O 2. VC. moves from the periphery to the heart muscle. The differences are in pressure. So blood is ejected from the left ventricle under a pressure of 120 millimeters of mercury. Further, the pressure decreases, and in the capillaries it is about 10 units.

Blood fluid also moves slowly through the veins of the systemic circle, because where it flows, it has to overcome gravity and cope with the obstacle of the valves.

In medicine, blood sampling for a detailed analysis is always taken from a vein. Sometimes from capillaries. Biological material taken from a vein helps determine the condition of the human body.

The difference between venous bleeding and arterial bleeding

It is not difficult to distinguish between types of bleeding; even people far from medicine can do this. If an artery is damaged, the blood is bright red.

It flows in a pulsating stream and flows out very quickly. Bleeding is difficult to stop. This main danger arterial damage.

It will not stop without first aid:

The affected limb should be elevated.
Hold the damaged vessel a little above the wound with your finger and apply a medical tourniquet. But it cannot be worn for more than one hour. Before applying a tourniquet, wrap the skin with gauze or any cloth.
The patient should be urgently taken to the hospital.

Arterial bleeding may be internal character. It is called closed form. In this case, a vessel inside the body is damaged, and the blood mass enters the abdominal cavity or spills between organs. The patient suddenly becomes ill, the skin turns pale.

A few moments later he begins to severe dizziness, and he loses consciousness. This indicates a lack of O 2. Only doctors in the hospital can help with internal bleeding.

When bleeding from a vein, fluid flows out in a slow stream. Color – dark burgundy. Bleeding from a vein can stop on its own. But it is recommended to bandage the wound with a sterile bandage.

There is arterial, venous and capillary blood in the body.

The first moves through the arteries of the large ring and veins small system blood circulation

Venous blood flows through the veins of the greater ring and pulmonary arteries small circle. A.K. saturates cells and organs with oxygen.
Taking carbon dioxide and decay elements from them, the blood turns into venous. It delivers metabolic products to the lungs for further elimination from the body.

Video: Differences between arteries and veins

To properly help a person with bleeding, you need to know exactly how. For example, arterial and venous bleeding requires a special approach. Arterial and venous blood are different from each other.

Blood in human body passes through two circles - large and small. The large circle is formed by arteries, the small circle by veins.

Arteries and veins are connected to each other. Small arterioles and venules branch off from large arteries and veins. And they, in turn, are connected by the thinnest vessels - capillaries. They are the ones who exchange oxygen for carbon dioxide and deliver nutrients our organs and tissues.

Arterial blood passes through both circles, both arteries and veins. It flows through the pulmonary veins into the left atrium. Carries and then gives oxygen to tissues. Tissues exchange oxygen for carbon dioxide.

Having given up oxygen, a person’s arterial blood, saturated with carbon dioxide, turns into venous blood. It returns to the heart, and then, through the pulmonary arteries, to the lungs. It is the venous one that is taken for most tests. It contains fewer nutrients, including sugar, but more products metabolism such as urea.

Functions in the body

Arterial blood carries oxygen, nutrients, and hormones throughout the body.
Venous, unlike arterial, carries carbon dioxide from tissues to the lungs, metabolic products to the kidneys, intestines, sweat glands. By folding, it protects the body from blood loss. Warms organs that need warmth. Venous blood is flowing not only through the veins, but also through the pulmonary artery.

Differences

The color of venous blood is dark red with a bluish tint. It is warmer than arterial water, its acidity is lower, and its temperature is higher. There is no oxygen in her hemoglobin, carbhemoglobin. In addition, it flows closer to the skin.
Arterial - bright red, saturated with oxygen and glucose. Oxygen in it is combined with hemoglobin to form oxyhemoglobin. The acidity is much higher than in the venous. It comes out to the surface of the skin on the wrists and at the neck. Flows much faster. That's why it's hard to stop her.

Signs of bleeding

Before medical assistance in case of bleeding, this means stopping or reducing blood loss until the ambulance arrives. It is necessary to distinguish between types of bleeding and use it correctly necessary funds to stop them. It is important to have dressings in your home and car first aid kits.

The most dangerous species bleeding - arterial and venous. The main thing here is to act quickly, but do no harm.

At arterial bleeding blood flows in bright scarlet intermittent fountains at high speed in time with the heartbeat.
With venous, a continuous or weakly pulsating dark cherry stream of blood flows from the injured vessel. If the pressure is low, a blood clot forms in the wound and blocks the blood flow.
With capillary, bright blood slowly spreads over the entire wound or flows in a thin stream.

First aid

When providing first aid for bleeding, it is important to determine its type and, depending on this, act.

If an artery in the arm or leg is affected, a tourniquet must be applied above the affected area. While the tourniquet is being prepared, press the artery above the wound to the bone. This is done with a fist or by pressing hard with your fingers. Elevate the injured limb.

Place it under the tourniquet soft cloth. You can use a scarf, rope, or bandage as a tourniquet. The tourniquet is tightened until the bleeding stops. You need to place a piece of paper under the tourniquet to indicate the time of application of the tourniquet.

ATTENTION. For arterial bleeding, the tourniquet can be held for two hours in the summer, and half an hour in the winter. If medical help is still not available, loosen the tourniquet for a few minutes while holding the wound with a clean cloth pad.

If a tourniquet cannot be applied, for example, in case of injury iliac artery, make a tight tampon with a sterile or at least clean cloth. The tampon is wrapped with bandages.

At venous bleeding a tourniquet or tight bandage is applied below the wound. The wound itself is covered with a clean cloth. The affected limb needs to be raised higher.

For these types of bleeding, it is good to give the victim painkillers and cover him with warm clothes.

In case of capillary bleeding, the wound is treated with hydrogen peroxide, bandaged or covered with a bactericidal adhesive plaster. If it seems to you that the blood is darker than a normal wound, then the venule may be damaged. Venous blood is darker than capillary blood. Proceed as if you had damaged a vein.

IMPORTANT. Capillary bleeding is dangerous if blood clotting is poor.

From the right help During bleeding, a person’s health and sometimes life depends.

The vascular system maintains constancy in our body, or homeostasis. She helps him in the processes of adaptation, with her help we withstand significant physical exercise. Prominent scientists, since ancient times, have been interested in the structure and operation of this system.

If you imagine the circulatory apparatus as closed system, then its main components will be two types of vessels: arteries and veins. Each performs a specific set of tasks and transfers different types blood. How venous blood differs from arterial blood will be discussed in the article.

The task of this type is the delivery of oxygen and useful substances to organs and tissues. She flows from the heart, rich in hemoglobin.

The color of arterial and venous blood is different. The color of arterial blood is bright red.

The largest vessel through which it moves is the aorta. She is characterized by high speed movements.

If bleeding occurs, stopping it requires effort due to its pulsating nature under high pressure. The pH is higher than that of the venous one. On the vessels through which this type moves, doctors measure the pulse(on the carotid or radial).

Deoxygenated blood

Venous blood is the one that flows back from the organs to return carbon dioxide. It doesn't have useful microelements, carries a very low concentration of O2. But it is rich in metabolic end products and contains a lot of sugar. It is characterized by a higher temperature, hence the expression “warm blood.” To conduct laboratory diagnostic measures that's what they use. All medications nurses administer through veins.

Human venous blood, unlike arterial blood, has a dark, burgundy color. The pressure in the venous bed is low, the bleeding that develops when the veins are damaged is not intense, the blood oozes out slowly, and is usually stopped with a pressure bandage.

To prevent its reverse movement, the veins have special valves that prevent backward flow; the pH is low. There are more veins in the human body than arteries. They are located closer to the surface of the skin and are clearly visible visually in people with a light color type.

Once again about the differences

The table shows Comparative characteristics what arterial and venous blood is.

Attention! Most frequently asked question- Which blood is darker: venous or arterial? Remember - venous. It is important not to confuse this when getting into emergency. With arterial bleeding, the risk of losing a large volume in a short period of time is very high, and there is a threat fatal outcome, urgent measures need to be taken.

Circulation circles

At the beginning of the article, it was noted that blood moves in the vascular system. From school curriculum Most people know that movement is circular, and there are two main circles:

Big (BKK).
Small (MCC).

In mammals, including humans, the heart has four chambers. And if you add up the length of all the vessels, you get a huge figure - 7 thousand square meters.

But it is precisely this area that makes it possible to supply the body with O2 in the required concentration and not cause hypoxia, that is oxygen starvation.

BCC begins in the left ventricle, from which the aorta emerges. It is very powerful, with thick walls, with strong muscle layer, and its diameter in an adult reaches three centimeters.

It ends in the right atrium, into which 2 vena cava flow. The ICC originates in the right ventricle from pulmonary trunk, and closes in the left atrium with the pulmonary arteries.

Oxygen-rich arterial blood flows in a large circle, it is directed to each organ. As they progress, the diameter of the vessels gradually decreases to very small capillaries, which give away everything useful. And back, along the venules, gradually increasing their diameter to large vessels, such as the superior and inferior vena cava, the depleted venous flows.

Once in right atrium, through a special hole, it is pushed into the right ventricle, from which the small circle, pulmonary, begins. The blood reaches the alveoli, which enrich it with oxygen. Thus, venous blood becomes arterial!

Something very surprising happens: arterial blood moves not through the arteries, but through the pulmonary veins, which flow into the left atrium. Blood saturated with a new portion of oxygen enters the left ventricle and the circles are repeated again. That's why the statement that venous blood moves through the veins is incorrect, here everything works the other way around.

Fact! In 2006, a study was conducted on the functioning of the BCC and MCC in people with poor posture, namely scoliosis. Attracted 210 people under 38 years of age. It turned out that in the presence of scoliotic disease, there is a disruption in their work, especially among adolescents. In some cases, requiring surgical treatment.

For some pathological conditions Possible disruption of blood flow, namely:

organic heart defects;
functional;
pathologies venous system: , ;
, autoimmune processes.

Normally there should be no mixing. During the neonatal period, there are functional defects: open oval window, open Batalov duct.

After a certain period of time, they close on their own, do not require treatment and are not life-threatening.

But severe valve defects, reversal of the main vessels, or transposition, absence of a valve, weakness of the papillary muscles, absence of a heart chamber, combined defects– life-threatening conditions.

That is why, to the expectant mother it is important to undergo screening ultrasound examinations fetus during pregnancy.

Conclusion

The functions of both types of blood, arterial and venous, are undeniably important. They maintain balance in the body and ensure it full-time job. And any violations contribute to a decrease in endurance and strength, and worsen the quality of life.

Venous blood flows from the heart through the veins. It is responsible for moving carbon dioxide throughout the body, which is necessary for blood circulation. The main difference between venous blood and arterial blood is that it has more high temperature and contains less vitamins and microelements.

Arterial blood flows in capillaries. This smallest points on the human body. Each capillary carries a certain amount of liquid. The entire human body is divided into veins and capillaries. It's flowing there certain type blood. Capillary blood gives a person life and ensures the flow of oxygen throughout the body and most importantly to the heart.

Arterial blood is red and flows throughout the body. The heart pumps it to all remote corners of the body, so that it circulates everywhere. Its mission is to saturate the entire body with vitamins. This process keeps us alive.

Venous blood is blue-red in color, contains metabolic products, and flows through veins with very thin walls. She withstands the impact high pressure, because when the heart contracts, drops can form that the vessels must withstand. Veins are located above the arteries. They are easy to see on the body and easier to damage. But venous blood is thicker than arterial blood and flows out more slowly.

The most severe wounds for humans are the heart and groin. These places must always be protected. All the blood in a person flows through them, so with the slightest damage a person can lose all the blood.

There is a large and small circle of blood circulation. In the small circle, the liquid is saturated with carbon dioxide and flows to the lungs from the heart. It leaves the lungs, saturated with oxygen, and enters big circle. Blood, based on carbon dioxide, runs from the lungs to the heart; through the capillaries, the lungs carry blood based on vitamins and oxygen.

Oxygenated blood is located on the left side of the heart, and venous blood is located on the right. During the contraction of the heart, arterial blood enters the aorta. This is the main vessel of the body. From there, oxygen flows down and ensures the functioning of the legs. The aorta is the most important artery for humans. It, like the heart, cannot be damaged. This can lead to rapid death.

The role and functions of venous blood

Venous blood is often used for human research. It is believed that it speaks better about human diseases, because it is a consequence of the work of the body as a whole. In addition, it is not difficult to take blood from a vein, because it flows worse than a capillary, so a person will not lose much blood during the operation. The largest human arteries should not be damaged at all, and if it is necessary to do a study of arterial blood, it is taken from a finger in order to minimize the negative consequences for the body.

Venous blood is used by doctors for prevention diabetes mellitus. It is necessary that the level of sugar in the veins does not exceed 6.1. Arterial blood is clear liquid, which flows through the body, nourishing all organs. Venous absorbs the waste products of the body, cleansing it. Therefore, it is by this type of blood that human diseases can be determined.

Bleeding can be external and internal. Internal is more dangerous for the body and occurs when human tissue is damaged with inside. Most often, this occurs after a very deep external wound or a malfunction in the body leading to tissue rupture from the inside. Blood begins to flow into the crack, and the body feels oxygen starvation. The person begins to turn pale and loses consciousness. This occurs because too little oxygen reaches the brain. Venous blood can be lost due to internal bleeding and this will be harmless to humans, but arterial blood is not. Internal bleeding quickly blocks brain function due to lack of oxygen. This will not happen with external bleeding, because the connection between human organs is not disrupted. Although, loss large quantity blood is always fraught with loss of consciousness and death.

Summary

So, the main difference between venous blood and arterial blood is this color. Venous is blue, and arterial is red. Venous is rich in carbon dioxide, and arterial is rich in oxygen. Venous flows from the heart to the lungs, where it turns into arterial, saturated with oxygen. The arterial flows through the aorta from the heart throughout the body. Venous blood contains metabolic products and glucose, arterial blood is saltier.

Arterial blood is located on the left side of the heart, venous blood on the right. Blood should not mix. If this happens, it will increase the workload on the heart and reduce physical abilities person. In lower animals, the heart consists of one chamber, which inhibits their development.

Both types of blood are very important for humans. One feeds it, and the other collects it harmful substances. In the process of blood circulation, blood passes one into another, which ensures the functioning of the body and the structure of the body that is optimal for life. The heart pumps blood at high speed and does not stop working, even during sleep. This is very difficult for him. The division of blood into two types, each of which performs its own functions, allows a person to develop and improve. Such a structure circulatory system helps us remain the most intelligent among all creatures born on Earth.