Health

How to stay healthy in changing weather conditions

The weather can be unpredictable, especially in late winter. One day it might be sunny and warm, the next day it might be freezing and snowy. How does this changing weather affect your health and well-being? And what can ...

Diseases, Conditions, Syndromes

Human vascular organoids reveal clues for a potential COVID treatment

When the new SARS-CoV-2 virus began killing thousands of people every week, physicians and scientists around the globe raced to learn why the new pathogen was so deadly. Among many early findings, experts noted that the infection ...

Diseases, Conditions, Syndromes

Researchers find genetic cause of Raynaud's phenomenon

Researchers at Queen Mary University of London's Precision Healthcare Research Institute (PHURI) and the Berlin Institute of Health (BIH) at Charité—Universitätsmedizin Berlin have identified the genetic causes of Raynaud's ...

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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