An overview of the circulatory system in the human body

Unlike the thymus, the bone marrow does not atrophy at puberty, and therefore there is no concomitant decrease in the production of B lymphocytes with age. The systemic circulation provides organstissues and cells with blood so that they get oxygen and other vital substances.

The white pulp contains both B and T lymphocytes. The pulmonary circulation is where the fresh oxygen we breathe in enters the blood.

The capillaries form a fine network around the pulmonary vesiclesgrape-like air sacs at the end of the airways. Lymph nodes The lymph nodes, or lymph glands, are small, encapsulated bean-shaped structures composed of lymphatic tissue.

Lymphatic system

The fluid and proteins within the tissues begin their journey back to the bloodstream by passing into tiny lymphatic capillaries that infuse almost every tissue of the body. Stem cells destined to become B lymphocytes remain in the bone marrow as they mature, while prospective T cells migrate to the thymus to undergo further growth.

The arteries carry blood away from the heart; the veins carry it back to the heart. The blood from the right chamber must flow through the vena arteriosa pulmonary artery to the lungs, spread through its substances, be mingled there with air, pass through the arteria venosa pulmonary vein to reach the left chamber of the heart and there form the vital spirit Only three copies of the book survived but these remained hidden for decades, the rest were burned shortly after its publication in because of persecution of Servetus by religious authorities.

The primary oxygen transporter molecule is hemocyanin. Where to get help In an emergency, always call triple zero Things to remember The circulatory system delivers oxygen and nutrients to cells and takes away wastes.

The suitability of any of the described options in an individual case can be determined by talking to a doctor. This is where carbon dioxide is released from the blood into the air contained in the pulmonary vesicles and fresh oxygen enters the bloodstream.

The functional tissue of the spleen is made up of two types of cells: The system of blood vessels resembles a tree: This is known as single cycle circulation. As the body uses the oxygen and processes nutrients, it creates carbon dioxide, which your lungs expel as you exhale.

Richards were awarded the Nobel Prize in Medicine "for their discoveries concerning heart catheterization and pathological changes in the circulatory system. Blood circulation starts when the heart relaxes between two heartbeats: Spleen The spleen is found in the abdominal cavity behind the stomach.

Some animals, such as jellyfishhave more extensive branching from their gastrovascular cavity which functions as both a place of digestion and a form of circulationthis branching allows for bodily fluids to reach the outer layers, since the digestion begins in the inner layers.

These vessels converge to form one of two large vessels called lymphatic trunks, which are connected to veins at the base of the neck. There are free-floating cells, the hemocyteswithin the hemolymph.

The blood vascular system first appeared probably in an ancestor of the triploblasts over million years ago, overcoming the time-distance constraints of diffusion, while endothelium evolved in an ancestral vertebrate some — million years ago.

Only a few regions, including the epidermis of the skinthe mucous membranesthe bone marrowand the central nervous systemare free of lymphatic capillaries, whereas regions such as the lungsgutgenitourinary systemand dermis of the skin are densely packed with these vessels.

Because blood pools in the veins after death, arteries look empty. Hemolymph is composed of waterinorganic salts mostly sodiumchlorinepotassiummagnesiumand calciumand organic compounds mostly carbohydratesproteinsand lipids.

Using the network of arteries, veins and capillaries, blood carries carbon dioxide to the lungs for exhalation and picks up oxygen. The other trunk, the thoracic ductdrains the rest of the body into the left subclavian vein.

Lymph, along with antigens, drains into the node through afferent incoming lymphatic vessels and percolates through the lymph nodewhere it comes in contact with and activates lymphocytes.

The thymus has no afferent incoming lymphatics, which supports the idea that the thymus is a T-cell factory rather than a rest stop for circulating lymphocytes.

Circulatory system

Learn More in these related Britannica articles: The contractions of the chambers make the sound of heartbeats. Other, less-organized regions of the gut also play a role as secondary lymphoid tissue.

The heart of fish is, therefore, only a single pump consisting of two chambers. In the systemic circulationthe left ventricle pumps oxygen -rich blood into the main artery aorta. In amphibians and most reptiles, a double circulatory system is used, but the heart is not always completely separated into two pumps.

March Other animals While humans, as well as other vertebrateshave a closed cardiovascular system meaning that the blood never leaves the network of arteriesveins and capillariessome invertebrate groups have an open cardiovascular system. Blood flowed from both creating organs to all parts of the body where it was consumed and there was no return of blood to the heart or liver.

He ascribed the fact to the phenomenon that air escaping from an artery is replaced with blood that entered by very small vessels between veins and arteries.

This type of circulation provides the heart with oxygenated blood so it can function properly.Aug 01,  · There is not only one blood circulatory system in the human body, but two, which are connected: The systemic circulation provides organs, tissues and cells with blood so that they get oxygen and other vital substances.

THE HUMAN BODY SYSTEMS System Function Diagram Major Organs Interactions- Working with Other Systems Digestive 1. take in food (ingestion) circulatory system-reaches places other one can’t – between cells) Lymph (liquid part of blood – plasma, when it’s in lymph vessels) Lymph Vessels.

Lymphatic system, a subsystem of the circulatory system in the vertebrate body that consists of a complex network of vessels, tissues, and organs. The lymphatic system helps maintain fluid balance in the body by collecting excess fluid and particulate matter from tissues and depositing them in the bloodstream.

The circulatory system delivers oxygen and nutrients to cells and takes away wastes. The heart pumps oxygenated and deoxygenated blood on different sides.

The types of blood vessels include arteries, capillaries and veins.


All cells in the body need to have oxygen and nutrients, and they need their. The human circulatory system (simplified). Red indicates oxygenated blood carried in arteries, blue indicates deoxygenated blood carried in veins. Capillaries, which join the arteries and veins, and the lymphatic vessels are not shown.

Combined with the cardiovascular system, the circulatory system helps to fight off disease, helps the body maintain a normal body temperature, and provides the right chemical balance to provide.

An overview of the circulatory system in the human body
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