New spray gel could help take the bite out of frostbite

Mountaineers and winter sports enthusiasts know the dangers of frostbite—the tissue damage that can occur when extremities, such as the nose, ears, fingers and toes, are exposed to very cold temperatures. However, it can ...

Lab-made blood vessels: Mechanics matters

Biodegradable tubes that turn into living blood vessels once implanted in the human body. In an imaginary, modern remake of Fantastic Voyage, Isaac Asimov would probably navigate his submersible through the folds of our cardiovascular ...

Direct detection of circulating tumor cells in blood samples

Tumor cells circulating in blood are markers for the early detection and prognosis of cancer. However, detection of these cells is challenging because of their scarcity. In the journal Angewandte Chemie, scientists have now ...

Hybrid device may help doctors treat strokes more quickly

Stroke, one of the leading causes of death worldwide, is normally caused by poor blood flow to the brain, or cerebral ischemia. This condition must be diagnosed within the first few hours of the stroke for treatment to be ...

A more sensitive device for characterizing DNA in blood circulation

Developed and patented in 2012 and 2014 in the Laboratoire d'Analyse et d'Architecture des Systèmes (LAAS-CNRS) and implemented industrially by Picometrics-Technologies, BIABooster technology characterizes DNA with new precision ...

Researcher uses microscale technology to isolate rare cells

In a blood sample taken from a cancer patient, there may be a single circulating tumor cell among hundreds of thousands of other cells. These tumor cells can provide valuable information about how cancer progresses, and could ...

page 1 from 3

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