Physics of the Heart

921 Words2 Pages
bulb-icon

Recommended: Study for heart anatomy and physiology II

In the US, heart attacks kill more people than any other single cause. Many of the deaths are caused by electrical disturbances in a damaged heart that cause it to fibrillate (Pool). Despite current overwhelming interest in the operations of the human heart, for most of history the human heart has been regarded as a "forbidden organ too delicate to tamper with" (NOVA). In fact, it might have remained so, were it not for World War II where military doctors, faced with massive numbers of injuries ushered the world into our current medical trajectory.

Your body has about 5.6 liters of blood. All of this blood circulates through the body three times every minute. In one day, the blood travels a total of 12,000 miles (NOVA). Rhythmic contractions of the heart pump blood occur in response to electrical control pulse sequences. Active cells in the sinoatrial node in the heart trigger a sequence of electrical events that control muscle contractions, which pump the blood.

Scientific interest in the heart goes back centuries. Some of the most basic understandings about the operation and specifically the electrical currents of the heart were discussed during the May 17, 1888 Proceedings of the Royal Society of London by Professor J.A. McWilliam of the University of Aberdeen. The following conclusions were based on his studies of mammalian hearts in cats, dogs, rabbits, rats, hedgehogs, and guinea-pigs.

* An all or nothing approach to heart contraction

o If a stimulus was strong enough to excite contraction, it produced a maximal contraction

* The application of interrupted currents induces fibrillar contractions which can be recovered from even after long period under the combined influence of artificial respira...

... middle of paper ...

...n that prevents the heart from immediately contracting again.

Bibliography

1. "Cactus Picture" March 16, 2005.

2. Campbell, Neil A. (2002) "Biology" 6th edition. Benjamin Cummings. San Francisco, CA.

3. Kay, Ian. (1998) "Introduction to Animal Physiology" Springer-Verlag New York Inc.

4. McWilliam, J.A. (1888) "On the Rhythm of the Mammalian Heart" Froceedings of the Royal Society of London, Vol. 44, pages 206-208.

5. NOVA. " Cut to the Heart” PBS Online 1997.

6. Pool, Robert. (1990) “Heart Like a Wheel” Science, Vol. 247, No. 4948, pages 1294-1295.

7. Putnam, Jeremiah L. "Heart Diagram" Professor of Biology. Davidson College.

8. Schmidt-Nielsen, Knut. (1997) "Animal Physiology: Adaptation and environment" Fifth Edition. Cambridge University Press. New York, NY.

Show More
Related

  • Pygmy Three-Toed-Sloth Analysis

    926 Words  | 2 Pages

    3 Apr. 2014. The 'Standard' of the 'Standard'. http://eol.org/pages/323582/details>. Evans, Arthur V., Rosser W. Garrison, Neil Schlager, and Michael Hutchins. Grzimeks' Animal Life Encyclopedia.

    Read More

  • 1.3 Explain The Cardiac Cycle Essay

    581 Words  | 2 Pages

    1.2 & 1.3 Explain The Cardiac Cycle And Describe How The Heart Rate Is Modified According To The Needs Of The Body

    Read More

  • Successful Aging Elderly (SAE)

    2206 Words  | 5 Pages

    ... middle of paper ... ... Larson, R. (1978). The Species of the World.

    Read More

  • Pulse Wave Analysis Essay

    1900 Words  | 4 Pages

    O’Rourke [13] describes the pulse wave shape as: “A sharp upstroke, straight rise to the first systolic peak, and near-exponential pressure decay in the late diastole.” Arteries are compliant structures, which buffer the pressure change resulting from the pumping action of the heart. The arteries function by expanding and absorbing energy during systole (contraction of the cardiac muscle) and release this energy by recoiling during diastole (relaxation of the cardiac muscle). This function produces a smooth pulse wave comprising a sharp rise and gradual decay of the wave as seen in Figure 5. As the arteries age, they become less compliant and do not buffer the pressure change to the full extent. This results in an increase in systolic pressure and a decrease in diastolic pressure.

    Read More

  • Sheep Heart Dissection

    1386 Words  | 3 Pages

    of the heart: one chamber is on the top and one chamber is on the

    Read More

  • The First Artificial Heart Transplant

    742 Words  | 2 Pages

    The development of the artificial heart began in the early 1950’s. The initial prototype, developed in 1970’s by the artificial developmental staff at the University of Utah, allowed 50 hours of sustained life in a sheep. Although this was called a success, the implantation of the artificial heart left the sheep in a weakened state. It wasn’t until late 1970’s and the early 1980’s where the improvement of the artificial heart actually received attention as a possible alternative to a heart transplant. The remodeled product of the early 1970’s did more than just the 50 hours of sustained life; it enabled the cow to live longer and to live a relatively normal life, with the exception of a machine attached to the animal.

    Read More

  • Heart Health: How Does Heart Rate Change with Exercise?

    831 Words  | 2 Pages

    The science and history of the heart can be traced back as far as the fourth century B.C. Greek philosopher, Aristotle, declared the heart to be the most vital organ in the body based on observations of chick embryos. In the second century A.D, similar ideas were later reestablished in a piece written by Galen called On the Usefulness of the Parts of the Body. Galen’s thesis was that the heart was the source of the body’s essential heat and most closely related to the soul. Galen made careful observations of the physical properties of the heart as well. He said “The heart is a hard flesh, not easily injured. In hardness, tension, in general strength, and resistance to injury, the fibers of the heart far surpasses all others, for no other instrument performs such continues, hard work as the heart”(Galen, Volume 1).

    Read More

  • Comparison Between “The Cask of Amontillado” and “The Tell-Tale Heart”

    2130 Words  | 5 Pages

    Chua, John. "An overview of 'The Tell-Tale Heart,'." Gale Online Encyclopedia. Detroit: Gale, 2010. Literature Resources from Gale. Web. 7 Dec. 2010.

    Read More

  • The Impact of the Little Rock Nine

    1198 Words  | 3 Pages

    Works Cited Bates, D. (1957, December 17). Letter from Roy Wilkins. Little Rock, Arkansas, United States of America. Beals, M. P. (1994). The Species of the World.

    Read More

  • X-linked Agammaglobulinemia

    1397 Words  | 3 Pages

    VanPutte, C., Regan, J., & Russo, A. (2014). Seeley's anatomy & physiology(10th ed.). NEW YORK, NY: MCGRAW-HILL.

    Read More

  • Symptoms and Causes of Heart Attacks

    631 Words  | 2 Pages

    Approximately one million Americans suffer a heart attack annually. Four hundred thousand of these victims die as a result. Many of the heart attack deaths are due to ventricular fibrillation of the heart that occurs before the victim can reach any medical assistance or the emergency room. These electrical disturbances of the heart can be treated with medications once the patient reaches the hospital. Therefore, 90% to 95% of heart attack victims who make it to the hospital survive. The 5% to 10% who later die are those who have suffered major heart muscle damage.

    Read More

  • Leading Causes of Death in The United States

    2023 Words  | 5 Pages

    One of the leading causes of death in the United States is heart disease. “Approximately every 29 seconds one American will have a heart attack, and once a minute one American will die from a heart attack” (Ford-Martin and Odle, 915). According to the Gale Encyclopedia of Alternative Medicine men over the age of 45 and women over the age of 55 are considered at risk for heart disease. Heart disease is a major cause of death. It is beneficial to individuals who seek to prevent heart disease to recognize the risks leading to heart attacks as they are one of the primary indications of developing heart disease; especially those that fall into the at risk age groups. These risks consist of some that cannot be changed such as heredity risks, or those that can change such as smoking habits. It is very important to know these specific risks for prevention and to understand the symptoms of heart attacks, such as sweating or the feeling of weakness so if these or other symptoms occur people are aware. Finally heart disease treatment is of vital importance if you experience a heart attack so you can learn how to prevent another one from occurring.

    Read More

  • The Cardiovascular System

    1238 Words  | 3 Pages

    The cardiovascular system is made up of the heart which pumps blood to the lungs through pulmonary circulation, the heart muscle through cardial circulation and the body systems through systematic circulation. It is made up of various chambers and valves and its cycle is controlled by an electrical signal originating in the heart itself. There are various different vessels which control the blood flow throughout the body. Which include high pressure arteries and arterioles originate from the heart. Capillaries which have a semipermeable membrane that allows the exchange of gasses, nutrients and wastes between the blood and the tissues. Also veins which are low pressure and contain valves that prevent backflow. All of these together perform the main functions of the cardiovascular system; protection, transportation and regulation.

    Read More

  • Types Of Eating Disorders

    840 Words  | 2 Pages

    Martini, Nath, Bartholomew. (2012). Fundamentals of Anatomy and Physiology Ninth Edition. In N. B. Martini, Fundamentals of Anatomy and Physiology Ninth Edition (pp. Chapter 25; 917-952). San Francisco: Pearson Education.

    Read More

  • The Heart

    1796 Words  | 4 Pages

    The Heart is a very important organ in the body. It is what keeps your blood flowing and your organs going. It is a tireless muscle that pumps more than two thousand gallons of blood every day. The blood that is pumped is filled with nutrition and oxygen (Colombo 7). It travels through out your body in less than sixty seconds. So it needs to be taken extra good care of. When abuse is put on the body, the heart’s performance is not at its best. The Heart is a major organ that needs loving and care. Everyone has only one and by abusing it, they are cutting their live span little by little. People can live their lives freely but how they choose to live them could be the difference between life and death.

    Read More

More about Physics of the Heart

Open Document