New record for world's smallest atomic valentine

(PhysOrg.com) -- Shattering their own world record from two years ago, scientists from the University of Birmingham in the UK have created the unofficial world’s smallest atomic valentine. Their tiny heart measures approximately ...

The first 3-D map of the heart's neurons

The normal functioning of our hearts is maintained by our body's control center—the brain—via an intricate network of nerves. When this communication is disrupted, it results in heart disease, including heart attacks, ...

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.

Bone, not adrenaline, drives fight or flight response

When faced with a predator or sudden danger, the heart rate goes up, breathing becomes more rapid, and fuel in the form of glucose is pumped throughout the body to prepare an animal to fight or flee.

A hydrogel that can stop bleeding from an artery

A team of researchers affiliated with several institutions in China has developed a hydrogel that can stop bleeding from a punctured artery. In their paper published in the journal Nature Communications, the group describes ...

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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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