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The Circulatory System: The Hydraulics of the Human Heart

The components of the circulatory system are run on hydraulic power. Similar to hydraulic machinery, the body uses two adjacent "lines" to transfer the "hydraulic fluid".

Now it's no secret that many ancient cultures were more than a bit preoccupied with the human body and the average person in 230 BC was likely exposed to much more of the inner-most parts of the body compared to any number of us (aside from those of us that work in the medical field), just by default. We, fortunately, don't have to hand-remove the heart of a recently deceased human being just to, well, see what it looks like — we have the internet! However, if we didn't know so much about each and every process…

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Articles of Interest

Cells of the Cardiovascular System

Blood and lymphatic vessels are populated by endothelial and smooth muscle cells arranged in concentric layers separated by fibrous sheaths. The heart’s muscular wall is comprised of cardiomyocytes lined with endothelial cells. The cells of the cardiovascular system include endothelial cells, vascular smooth muscle cells, lymphatic endothelial cells, cardiomyocytes, and atherosclerosis cells. Each of these cells plays a critical role in circulating, maintaining, and supporting cardiovascular activity, perfusion, and system development.

Demystifying the Circulatory System

There are many different structures and diseases associated with the cardiovascular or circulatory system, so it is easy to be confused.

Eyes: Windows to the cardiovascular system

Ophthalmologists and optometrists have a unique perspective on a patient’s cardiovascular system because the eye is the only place in the body where doctors get a glimpse of the health of a patient’s blood vessels without the use of imaging technology.

Functions of the Cardiovascular System

Knowing the functions of the cardiovascular system and the parts of the body that are part of it is critical in understanding the physiology of the human body. With its complex pathways of veins, arteries, and capillaries, the cardiovascular system keeps life pumping through you. The heart, blood vessels, and blood help to transport vital nutrients throughout the body as well as remove metabolic waste. They also help to protect the body and regulate body temperature.

General organization of the cardiovascular system

The primary function of the cardiovascular system is to deliver blood to the tissues, over long distances, and to evacuate waste products from the tissues.

How Long Does It Take Blood To Circulate Through Your Vascular System?

The answer is… 20 seconds. That’s pretty amazing considering the complex network of blood vessels – arteries, veins and capillaries – that carry blood through the body. According to The Cleveland Clinic, that system is over 60,000 miles long. That’s long enough to circle Earth twice!

Major Functions of the Cardiovascular System

The cardiovascular system acts as an internal road network, linking all parts of the body via a system of highways (arteries and veins), main roads (arterioles and venules) and streets, avenues and lanes (capillaries).

No one knew how our blood moved—until this doctor realized the heart is a pump

In 'The Wine-Dark Sea Within,' cardiologist Dhun Sethna describes a 17th-century insight that revolutionized medicine.

One day, scientists could grow the human cardiovascular system from stem cells

Scientists from Rice University and the Baylor College of Medicine are using 3D printers to make functioning capillaries. These are tiny, thin vessels that transport blood from the arteries to the veins and facilitate the exchange of oxygen, nutrients and waste products between the blood and tissues.

Our Circulatory System and Nervous System We could not live without them!

The circulatory system nourishes the entire nervous system. Both systems have specialized functions that work independently; however, together they depend on each other to make sure our bodies are working properly.

The Cardiovascular System: Mechanics and Dynamics

The cardiovascular (or circulatory) system is one of the most vital systems in the human body. This system provides a transport mechanism for oxygen through the body as a fuel source for cellular respiration, and then the return transport of carbon dioxide, a byproduct of cellular respiration, that the body expels as waste through breathing. It also provides for the transport of amino acids, nutrients, hormones, and the other components that make up blood. Cardiovascular diseases of varying sorts are among the leading causes of death in industrialized nations around the world.

The Circulatory System

There are a couple major reasons why we have a circulatory system. One is to get the nutrients from the area of the small intestine and the oxygen from the lungs to all the cells in the body. Our cells also need a way to get rid of their wastes. As we look closer at the human circulatory system, you'll see that there are some other tasks accomplished with the help of our "closed circulatory system" (also known as the Cardiovascular System).

The Circulatory System: An Amazing Circuit That Keeps Our Bodies Going

Not only does the circulatory system keep our cells healthy, but it also keeps us alive. The heart constantly receives signals from the rest of the body that direct how hard it needs to pump to properly supply the body with what it needs, according to Nemours. For example, when asleep, the body sends electrical signals to the heart that tell it to slow down. When participating in heavy exercise, the heart receives the message to pump harder to deliver extra oxygen to the muscles.

Veins and the Wonders of the Human Circulatory System

Early 20th century medicine believed that the heart was off limits and there was no sensible ways to cure or study the complex ailments of the heart. A German physician named Werner Forssmann was the first person to perform a self catheterization that proved the medical community wrong by showing that the heart could be studied through the veins. This painful experiment set the foundations to the study of cardiology. He threaded a thin tube through his vein, pushed it, and had it go all the way to the heart. As evidence of his discovery, the doctor had his assistant take an X-Ray to show that he had in fact reached the heart through the vein in his inner left elbow. He won the Nobel Prize in 1956 for his contribution.

Viewing vascular trees to diagnose disease

Researchers have created a 3D imaging system to analyse blood flow in limbs, which could be used to asses risk of diseases, such as cancer and arteriosclerosis (the clogging of the arteries).

Resources

Circulation Foundation

The Circulation Foundation funds and promotes research into the causes, treatment and prevention of vascular disease in the UK.

KenHub

The circulatory system is divided into two separate loops: The shorter pulmonary circuit that exchanges blood between the heart and the lungs for oxygenation; and the longer systemic circuit that distributes blood throughout all other systems and tissues of the body. Both of these circuits begin and end in the heart.

Physiopedia

The vasculature works with the heart to supply the body with oxygen and nutrients and to remove waste products.

StatPearls

The regulation of the cardiovascular system occurs via a myriad of stimuli, including changing blood volume, hormones, electrolytes, osmolarity, medications, adrenal glands, kidneys, and much more. The parasympathetic and sympathetic nervous systems also play a key role in the regulation of the cardiovascular system.