Power of human Heart and Brain

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Discussion Overview

The discussion revolves around the power output of the human heart and brain, specifically examining the calculations related to the heart's power and questioning the brain's energy consumption under average conditions. The scope includes theoretical considerations and biological mechanisms.

Discussion Character

  • Exploratory, Technical explanation, Conceptual clarification

Main Points Raised

  • One participant calculates the power of the heart to be approximately 1.111 watts based on blood flow and pressure, and questions whether the brain can be around 20 watts as mentioned in Michio Kaku's book.
  • Another participant asserts that the brain derives its energy from sugar and other molecules in the bloodstream, not from blood pressure.
  • A follow-up question seeks clarification on whether this energy comes from chemical reactions.
  • One participant confirms that nucleoside triphosphate (NTP) is specifically responsible for providing energy to brain cells.
  • A humorous remark suggests that the brain's power might be influenced by emotional states, such as anger.

Areas of Agreement / Disagreement

Participants express differing views on the source of the brain's energy, with some focusing on chemical processes while others emphasize the role of blood pressure. The discussion remains unresolved regarding the specific power output of the brain.

Contextual Notes

There are limitations in the assumptions made about the energy calculations and the definitions of power in biological contexts. The discussion does not resolve the mathematical steps involved in the power calculations.

gianeshwar
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If heart forces 4 litres of blood per minute and blood pressure is 125 mm of Hg column and we consider pulse rate as 60 beats per minute then by calculation power of heart comes as approx. 1.111 watts.
If I consider the person is just lying down and obviously brain is also active .
My question is " Can brain under these average conditions be of about 20 watts as told in Michio Kaku's book"Physics of the impossibe" as I remember.
 
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The brain isn't powered by the pressure of the blood. It gets its energy through the sugar etc molecules that are transported in that blood stream.
 
rumborak said:
The brain isn't powered by the pressure of the blood. It gets its energy through the sugar etc molecules that are transported in that blood stream.
Means energy from chemical reactions?
 
Yes. Specifically, a molecule called nucleoside triphosphate (NTP) is responsible for providing energy to cells.
 
rumborak said:
The brain isn't powered by the pressure of the blood.
Unless you get really angry.
 
Thank You friends!
 

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