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Blood and blood vessels carry cells, nutrients and oxygen around the body.

Blood and blood vessels carry cells, nutrients and oxygen around the body.
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Blood and blood vessels

Blood, the heart and the vessels that carry blood around the body together make up the cardiovascular system. They are vital for carrying nutrients, oxygen and waste around the body.

Blood is made of cells and plasma. There are three main types of blood cells – red cells, white cells and platelets. All are made in the marrow found in many bones.

Red blood cells deliver oxygen from the lungs to the rest of the body, and carry waste products to be released by the lungs or the kidneys. Red blood cells contain haemoglobin, which is the protein that binds and releases oxygen.

White blood cells are part of the immune system. They detect and fight infections or foreign molecules that enter the body.

Platelets are small cells that help the blood clot.

Plasma is the clearish fluid that carries the cells. It also carries the nutrients from our diet such as sugars, fats, proteins, vitamins and minerals.

As well as carrying cells, nutrients, oxygen and waste, blood also helps to regulate body temperature.

What are blood vessels?

Blood vessels carry blood around the body. The three main types of blood vessels are:

  • arteries that carry blood pumped from the heart – these are the largest and strongest
  • veins that return blood to the heart
  • capillaries, which are tiny vessels that connect arteries and veins, and allow blood to come into close contact with tissues for the oxygen, carbon dioxide, food and waste.

Blood leaves the heart in large arteries, then moves through progressively smaller ones to the capillaries in tissues. The blood then leaves the tissues in veins that get larger as they get closer to the heart.

The arteries can expand and contract to lower or increase blood pressure, according to your needs.

Diseases of blood and blood vessels

The blood can be affected by trauma or diseases in other parts of the body leading to anaemia, a lack of red blood cells that reduces supply of oxygen to tissues, or polycythaemia, in which there are too many red blood cells. Also, there are cancers of blood cells like leukaemia .

Problems with blood vessels can also lead to high blood pressure, heart attack and stroke.

Last reviewed: August 2017

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Blood and blood vessels

Find health conditions articles related to blood and blood vessels.

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Blood Clotting and Monitoring | myVMC

Normally, clotting only occurs when there is blood loss from a damaged blood vessel. However, there are several conditions that can cause blood clots to form in the absence of active bleeding.

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Learn interesting facts about your blood, why it is so important, the parts that make up blood and how these are produced. Our blood even changes as we age.

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Blood and bleeding - myDr.com.au

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Anticoagulants | myVMC

Anticoagulants are substances that work against the process of blood clotting. Normally, clotting only occurs when there is blood loss from a damaged blood vessel. However, there are several conditions that can cause blood clots to form in the absence of active bleeding. Currently there are two anticoagulants in use: warfarin and heparin.

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There are two types of haemorrhagic stroke or bleed in the brain. An aneurysm: weak spot in the wall of an artery that balloons out. An AVM:tangled mass of blood vessels (arteries and veins).

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Cutaneous small vessel vasculitis

Cutaneous small vessel vasculitis (CSVV) is a condition caused by inflammation of the skins blood vessels. It classically presents as areas of red or purple discoloration.

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The human cardiovascular system is made up of the heart, the blood it pumps and the blood vessels, veins and arteries, through which blood travels.

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Blood Clotting: Assessment Before Surgery | myVMC

Adequate blood clotting is very important if you are about to have a surgical procedure. Modern surgical techniques have resulted in an overall decrease in significant bleeding, but there has been an increase in blood clotting abnormalities that develop after exposure to an agent or compound. The increasing complexity of surgical and other invasive procedures has also presented challenges for the prevention of bleeding.

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Isosorbide Mononitrate is used to prevent angina pectoris. It dilates blood vessels and arteries, increases oxygen supply and reduces the heart's workload.

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