Diseases, Conditions, Syndromes

Critical blood shortages because of COVID-19

The COVID-19 pandemic is creating critical blood shortages in the U.S. "It's not due to more COVID-19 patients needing blood products. Rather, it's a lack of donations coming in," says Dr. Justin Kreuter, transfusion medicine ...

Diseases, Conditions, Syndromes

How coronavirus is upsetting the blood supply chain

The coronavirus, which causes the disease COVID-19, has created enormous anxiety, uncertainty, and disruption to our lives. Much has already been written about potential shortages of medicines and face masks, but little has ...

Diseases, Conditions, Syndromes

US urges elderly to stock up on groceries, prepare to stay home

US health authorities Monday urged Americans most at risk of developing a serious illness from the new coronavirus—the elderly and those with underlying conditions—to stock up on food and medicine and prepare to remain ...

Oncology & Cancer

Starve a tumor, feed a cell: How cancers can resist drugs

With drug resistance a major challenge in the fight against cancer, a discovery by University of California, Irvine biologists could offer new approaches to overcoming the obstacle. Their research reveals that a mechanism ...

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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