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 ...

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 ...

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 ...

New intracranial sensor serves to measure cerebral pressure

An increase in cerebral pressure may cause dementia and could destroy the brain. Companies have been seeking to find monitoring sensors that can be implanted into the brain, and read from outside the body. A tiny sensor may ...

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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