Cardiology

Newly discovered immune cell function vital to healing

Cardiovascular disease, the most common cause of death, is the result of oxygen deprivation as blood perfusion to affected tissue is prevented. To halt the development of the disease and to promote healing, re-establishment ...

Neuroscience

The neural mechanism of a circulatory response to stress

Although the heart beats autonomously, its function can be regulated by the brain in response to, for instance, stressful events. In a new study, researchers from the University of Tsukuba discovered a novel mechanism by ...

Diseases, Conditions, Syndromes

People with addiction more likely to get COVID-19, die

People who are addicted to drugs or other substances are more likely to contract COVID-19 and to be hospitalized or die from it, according to a National Institutes of Health study.

Cardiology

Tracking down the causes of heart attack

Heart attacks strike suddenly and have a range of different triggers. Researchers from Charité - Universitätsmedizin Berlin and the German Centre for Cardiovascular Research (DZHK) were able to uncover a further underlying ...

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Circulatory system

The circulatory system is an organ system that passes nutrients (such as amino acids and electrolytes), gases, hormones, blood cells, nitrogen waste products, etc. to and from cells in the body to help fight diseases and help stabilize body temperature and pH to maintain homeostasis. This system may be seen strictly as a blood distribution network, but some consider the circulatory system as composed of the cardiovascular system, which distributes blood, and the lymphatic system, which distributes lymph. While humans, as well as other vertebrates, have a closed cardiovascular system (meaning that the blood never leaves the network of arteries, veins and capillaries), some invertebrate groups have an open cardiovascular system. The most primitive animal phyla lack circulatory system. The lymphatic system, on the other hand, is an open system.

The main components of the human circulatory system are the heart, the blood, and the blood vessels. The circulatory system includes: the pulmonary circulation, a "loop" through the lungs where blood is oxygenated; and the systemic circulation, a "loop" through the rest of the body to provide oxygenated blood. An average adult contains five to six quarts (roughly 4.7 to 5.7 liters) of blood, which consists of plasma, red blood cells, white blood cells, and platelets. Also, the digestive system works with the circulatory system to provide the nutrients the system needs to keep the heart pumping.

Two types of fluids move through the circulatory system: blood and lymph. The blood, heart, and blood vessels form the cardiovascular system. The lymph, lymph nodes, and lymph vessels form the lymphatic system. The cardiovascular system and the lymphatic system collectively make up the circulatory system.

This text uses material from Wikipedia, licensed under CC BY-SA