The heart is a pump, and the blood goes round, and round, and round all the time. And why does it do that? Why can't it just have a rest? Well, the blood has to be kept moving around all the time ...

Narrator: Well here we are ladies and gentlemen, in the heart, the powerhouse of the circulatory system, the hardest working muscle in the entire human body! Your heart first pumps blood to your lungs ...

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Until 1628 few Europeans disputed the teachings of Galen, an accomplished Greek physician and scholar. Galen lived in the second century A.D., and his teachings would come to dominate European ...

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Abstract: In this paper, a state-space model is developed through theoretical analysis and numerical solutions to approximate the response of the human circulatory system. This system model has one ...

Jupiter’s Wild Youth May Have Reshaped the Entire Solar System Nov. 13, 2025 Simulations reveal that Jupiter’s rapid growth disrupted the early solar system, creating rings where new planetesimals ...

The skin is the body's largest organ and helps protect internal organs from harm. Hair helps protect the skin, regulates body temperature, and is part of the body's sensory system. Sweat glands help ...

Exercise is important for keeping the musculoskeletal system healthy. Bones support the body and protect vital organs. Skeletal muscles help move parts of the body by contracting. The musculoskeletal ...