Lighting up cardiovascular problems using nanoparticles

Heart disease and stroke are the world's two most deadly diseases, causing over 15 million deaths in 2016 according to the World Health Organization. A key underlying factor in both of these global health crises is the common ...

Grow your own blood vessel model in a dish

Personalised blood vessel testing kit could unravel causes and treatments for heart attack, stroke and vascular dementia, find scientists.

In Antarctica, tourists swim among penguins

"It's like getting stabbed," a tourist exclaims, as he plunges into the three-degree Celsius (37-Fahrenheit) water, all under the intrigued gaze of a group of penguins.

Researchers report first recording of a blue whale's heart rate

Encased in a neon orange plastic shell, a collection of electronic sensors bobbed along the surface of the Monterey Bay, waiting to be retrieved by Stanford University researchers. A lunchbox-sized speck in the vast waters, ...

Forests face climate change tug of war

In a world of rising levels of atmospheric carbon dioxide, plants should be happy, right? Experiments have shown that, yes, increased carbon dioxide does allow plants to photosynthesize more and use less water.

Faster heartbeat helps deer mice to survive at high altitudes

Mice living at high altitudes in the American West carry a genetic variant that increases their heart rate, helping them cope with the low oxygen levels that occur at high elevations. Rena Schweizer of the University of Montana ...

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Heart

The heart is a muscular organ in all vertebrates responsible for pumping blood through the blood vessels by repeated, rhythmic contractions, or a similar structure in annelids, mollusks, and arthropods. The term cardiac (as in cardiology) means "related to the heart" and comes from the Greek καρδιά, kardia, for "heart."

The heart of a vertebrate is composed of cardiac muscle, an involuntary striated muscle tissue which is found only within this organ. The average human heart, beating at 72 beats per minute, will beat approximately 2.5 billion times during a lifetime (about 66 years). It weighs on average 250 g to 300 g in females and 300 g to 350 g in males.

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