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Entropy within the Cell

Entropy within the Cell

A living cell's primary tasks of obtaining, transforming, and using energy to do work may seem simple. However, the second law of thermodynamics explains why these tasks are harder than they appear. None of the energy transfers in the universe are completely efficient. In every energy transfer, some amount of energy is lost in a form that is unusable. In most cases, this form is heat energy. Thermodynamically, heat energy is defined as the energy transferred from one system to another that...

Entropy

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Salt particles that have dissolved in water never spontaneously come back together in solution to reform solid particles. Moreover, a gas that has expanded in a vacuum remains dispersed and never spontaneously reassembles. The unidirectional nature of these phenomena is the result of a thermodynamic state function called entropy (S). Entropy is the measure of the extent to which the energy is dispersed throughout a system, or in other words, it is proportional to the degree of disorder of a...

Entropy

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The first law of thermodynamics is quantitatively formulated via an equation relating the internal energy of a system, the heat exchanged by it, and the work done on it. A quantitative formulation of the second law of thermodynamics leads to defining a state function, the entropy.
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Related Experiment Video

Updated: Nov 10, 2025

Hi-C: A Method to Study the Three-dimensional Architecture of Genomes.

Hi-C: A Method to Study the Three-dimensional Architecture of Genomes.

Published on: May 6, 2010

How Chaotic Is Genome Chaos?

James A Shapiro¹

¹Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637, USA.

|April 3, 2021

Summary

Cancer genome evolution is not chaotic. Identifying specific DNA change signatures reveals cellular systems driving tumor progression, offering new therapeutic targets.

Keywords:

DNA break repair alternative end-joining (alt-EJ)chromoanasynthesis chromoplexy chromothripsis class switch recombination (CSR)human papillomavirus (HPV)immunoglobulin VDJ joining retrotransposition target-primed reverse transcription (TPRT)

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Published on: May 28, 2007

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Last Updated: Nov 10, 2025

Hi-C: A Method to Study the Three-dimensional Architecture of Genomes.

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Microbial Communities in Nature and Laboratory - Interview

Microbial Communities in Nature and Laboratory - Interview

Published on: May 28, 2007

Area of Science:

Genomics
Cancer Biology
Molecular Oncology

Background:

Cancer genomes undergo punctuated evolution, marked by abrupt genome restructuring termed "genome chaos."
Understanding the mechanisms behind these genomic alterations is crucial for cancer research.

Purpose of the Study:

To determine if widespread cancer genome changes are truly chaotic.
To identify cellular systems responsible for genome restructuring and their associated DNA change signatures.

Main Methods:

Reviewing cell and molecular systems involved in genome restructuring.
Describing characteristic DNA change signatures resulting from these systems.
Examining case studies of genome restructuring influenced by cell type or viral infection.

Main Results:

Many restructured cancer genomes exhibit non-chaotic signatures.
These signatures can identify specific cellular systems driving major oncogenic transitions.
Cell type and viral infection significantly influence genome restructuring patterns.

Conclusions:

Cancer genome evolution, while punctuated, is not entirely chaotic.
Identifying "unchaotic" signatures allows for the pinpointing of cellular systems responsible for tumor progression.
This knowledge can lead to the development of targeted therapies to inhibit aggressive cancer development.