- #1
mee
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I know there are trillions of cells in an adult human body but how many atoms are in each cell?
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Discussion Overview
The discussion revolves around estimating the number of atoms in a single cell, exploring various methods and assumptions involved in such calculations. Participants consider both theoretical and practical approaches to arrive at an estimate.
Discussion Character
- Exploratory, Technical explanation, Conceptual clarification
Main Points Raised
- One participant notes the existence of trillions of cells in an adult human body and questions the number of atoms in each cell.
- Another participant suggests a method involving the average weight of an adult, the number of cells, and the relative abundances of common atoms in a cell to estimate the number of atoms.
- A different approach is proposed that uses the average volume of a cell and the volume of an atom to establish an upper bound on the number of atoms, expressed mathematically.
- Concerns are raised about the limitations of this upper bound due to the 3D structure of molecules and the space between them.
- A participant humorously acknowledges the crude nature of the upper bound estimation.
Areas of Agreement / Disagreement
Participants do not reach a consensus on a specific method or estimate for the number of atoms in a cell, and multiple competing views and approaches remain present in the discussion.
Contextual Notes
Limitations include assumptions about atomic volume, the complexity of molecular structures, and the variability in cell types that may affect the estimates.
- #2
Monique
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Very crude: What does the average adult weigh, divide by the number of cells. What are the most common atoms in a cell and what are their relative abundancies, what do they weigh on average. Divide the weight of a cell by the average weight of the atoms represented in a cell.. and there you get your number :)
Maybe someone already figured it out and you can find it on Google :)
Maybe someone already figured it out and you can find it on Google :)
- #3
arildno
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Even cruder, but it should be an upper bound on the number of atoms in a cell:
Let V be the average volume of a cell.
Then we should have the inequality for the number n atoms in a cell:
[tex]n\leq\frac{V}{\frac{4}{3}\pi{R}^{3}}[/tex]
Where R is an average value for an atomic radius
Let V be the average volume of a cell.
Then we should have the inequality for the number n atoms in a cell:
[tex]n\leq\frac{V}{\frac{4}{3}\pi{R}^{3}}[/tex]
Where R is an average value for an atomic radius
- #4
Monique
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But how much space is taken up by the 3D structure of a molecule, and how much space is there between molecules..
- #5
arildno
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That's why it's such an awfully crude upper bound 
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