Molecular Biology: The Language of Life and Its Transformative Power (Part 2)

Molecular Biology: The Language of Life and Its Transformative Power

 

by blogger lim ju boo (lin ru wu) 

 

Understanding Life from Molecules to Medicine

Molecular biology is the study of life at its most fundamental level, examining the structure, function, and interactions of biological molecules that form the basis of living organisms. It bridges the gap between genetics and biochemistry, and today it stands at the heart of modern biological and medical research.

From deciphering the structure of DNA in 1953 to designing lifesaving mRNA vaccines during the recent COVID-19 pandemic, molecular biology has revolutionized the way humanity understands and manipulates the processes of life.

1. Foundations of Molecular Biology

At its core, molecular biology investigates the behavior of macromolecules, especially nucleic acids (DNA and RNA) and proteins.

Nucleic Acids: DNA and RNA

DNA (deoxyribonucleic acid) stores genetic information in the form of genes. 

RNA (ribonucleic acid) acts as the messenger and interpreter of genetic information and plays roles in catalysis (ribozymes), regulation (miRNA), and protein synthesis.

Proteins

Proteins perform most cellular functions—from catalyzing reactions (enzymes) to transporting molecules, regulating gene expression, and defending against pathogens (antibodies).

2. The Central Dogma of Molecular Biology

Proposed by Francis Crick in 1958, the central dogma explains the directional flow of genetic information:

DNA  to RNA (translation)

RNA  to Protein (translation) 

Stage	Description
Replication	DNA makes exact copies of itself             during cell division.
Transcription	DNA is transcribed into messenger         RNA (mRNA).
Translation	Ribosomes read mRNA and assemble     amino acids into proteins.

3. Core Techniques in Molecular Biology

 

Modern molecular biology is driven by innovative laboratory techniques:

Technique	Purpose
PCR (Polymerase Chain Reaction)	Amplifies DNA for diagnostics and forensics.
Gel Electrophoresis	Separates DNA, RNA, or proteins by size.
DNA Cloning	Produces identical DNA copies using plasmids.
DNA Sequencing (NGS)	Reads nucleotide order, enables genome projects.
CRISPR-Cas9	Precise gene editing for correcting mutations.
Proteomics	Studies proteins with mass spectrometry.
Recombinant DNA Technology	Produces insulin, growth hormone, vaccines.

4. Molecular Biology and Related Fields

Molecular biology connects deeply with other branches of science:

Field	Relationship
Genetics	Studies heredity; molecular biology explains gene function.
Biochemistry	Studies chemical processes; molecular biology focuses on DNA, RNA, and proteins.
Cell Biology	Examines cellular function using molecular mechanisms.
Biotechnology	Applies molecular techniques for industry and medicine.

5. Applications of Molecular Biology

5.1 Medicine

1. Gene Therapy treats diseases like hemophilia by replacing faulty genes.

2. Cancer precision therapy targets tumor-specific mutations.

3. mRNA vaccines (Pfizer-BioNTech, Moderna) use genetic instructions to stimulate immunity.

4. Prenatal and carrier testing detect inherited disorders like thalassemia.

5.2 Agriculture

Development of drought-resistant crops (e.g. Bt corn).

5.3 Golden rice engineered to produce vitamin A.

Forensic Science 

DNA fingerprinting helps solve crimes and identify disaster victims. 

6. Evolutionary Biology

DNA comparison reveals evolutionary relationships among species.

Supports Darwin’s theory with molecular evidence.

7. Synthetic Biology

Scientists design artificial DNA circuits and even synthetic cells.

Genomics – study of entire genomes.

Transcriptomics – study of RNA expression patterns.

Proteomics and Metabolomics – understanding disease at system levels.

AI-driven molecular design – speed up drug discovery.

Ethical debates – over designer babies and gene editing.

Summary:

Molecular biology is not merely a discipline, it is a revolution that has changed science, medicine, and our understanding of life itself. By decoding the molecular language of DNA and proteins, humanity has gained the power not only to study life but to redesign it. With that power comes great responsibility, demanding ethics, wisdom, and compassion.

The Future of Molecular Biology

Molecular biology continues to evolve with big data and computational tools:

References

1. Watson, J. D., & Crick, F. H. C. (1953). Nature, 171(4356), 737–738.

2. Crick, F. (1958). Symposium of the Society for Experimental Biology, 12, 138–163.

3. Mullis, K. (1990). Nobel Lecture: The polymerase chain reaction.
Doudna, J. A., & Charpentier, E. (2014). Science, 346(6213), 1258096.

4. Alberts, B. et al. (2015). Molecular Biology of the Cell (6th ed.). Garland.

5. Lodish, H. et al. (2021). Molecular Cell Biology (9th ed.). W.H. Freeman.

6. National Human Genome Research Institute. Human Genome Project Timeline.

(We shall in the next two articles see how we can use molecular biology for the advancement of medicine, and how we can also use it in forensic science to detect and fight crimes using Malaysian murder cases as examples) 

Title: Molecular Biology: The Language of Life (An Introduction - Part 1)

 Molecular Biology: The Language of Life and Its Transformative Power Across Science,  Medicine to Forensic Investigations 

Dedicated to the pursuit of scientific truth and the beauty of life at the molecular level.

Molecular biology is one of the most dynamic and influential branches of modern science, shaping our understanding of life from the smallest molecular interactions to the complexity of organisms and ecosystems. Emerging in the mid-20th century from the fusion of genetics, biochemistry, and structural biology, molecular biology provided answers to questions that had puzzled scientists for centuries: How is hereditary information stored? How is it copied and passed from one generation to the next? How do cells know what to do, and how do they build themselves from simple chemical components? The birth of molecular biology transformed biology from a largely descriptive science into a mechanistic and predictive discipline based on universal molecular principles.

The history of molecular biology began with remarkable discoveries that illustrated the power of interdisciplinary thinking. In 1869, Swiss physician Friedrich Miescher isolated "nuclein" from white blood cells, unknowingly discovering DNA. Yet for decades, scientists believed that proteins were the carriers of genetic information due to their structural complexity. This assumption was overturned only in 1944 when Oswald Avery, Colin MacLeod, and Maclyn McCarty demonstrated that DNA, not protein, was the hereditary material in bacteria. This was soon followed by the Hershey-Chase experiment in 1952, which confirmed DNA's genetic role using viral infections of bacteria.

The true revolution began in 1953 when James Watson and Francis Crick, using X-ray crystallography data from Rosalind Franklin and Maurice Wilkins, proposed the now-famous double helix structure of DNA. This discovery revealed how DNA could both store information and replicate itself accurately, through complementary base pairing, laying the foundation for the new science of molecular biology. Just five years later, in 1958, Francis Crick proposed the "central dogma of molecular biology," which stated that genetic information flows from DNA to RNA to protein. Although later refined to accommodate discoveries like reverse transcription and RNA editing, the central dogma still provides a conceptual framework for understanding gene expression.

Since then, molecular biology has rapidly evolved, driving major scientific revolutions: recombinant DNA technology in the 1970s allowed genes to be cut and inserted into other organisms; PCR (polymerase chain reaction), developed by Kary Mullis in 1983, enabled the amplification of DNA; and in 2003 the Human Genome Project revealed the complete DNA sequence of humans. Today, technologies like CRISPR-Cas9 gene editing, epigenomics, and synthetic biology are ushering in a new era where we not only study life but can redesign it.

This article explores the foundations, mechanisms, tools, interdisciplinary scope, and profound applications of molecular biology in fields such as medicine, biotechnology, agriculture, forensic science, evolution, and environmental science. By tracing its development and examining its expanding applications, we will see how molecular biology has truly become the universal language of life.

Molecular biology rests upon an elegant yet powerful truth: all living organisms, from bacteria to humans, are built upon universal molecular principles. Despite the incredible diversity of life, the same four nitrogenous bases found in DNA - adenine, thymine, cytosine, and guanine - encode hereditary instructions in every known species. This astonishing conservation of molecular design unifies all organisms in a single biological continuum. In this way, molecular biology reveals a profound reality: life is both diverse and fundamentally unified at the molecular level.

At its foundation, molecular biology explores the molecular architecture and functions of cellular processes. It is concerned primarily with nucleic acids and proteins—molecules that store, transmit, and execute genetic information. DNA (deoxyribonucleic acid) serves as the long-term repository of genetic instructions required for the formation and maintenance of life, while RNA (ribonucleic acid) and proteins carry out the functional execution of those instructions. Together, they shape the biochemical identity of cells and enable growth, adaptation, and reproduction.

One of the most important conceptual breakthroughs in molecular biology was the discovery of the complementary nature of DNA strands, enabling faithful replication. During cell division, DNA unwinds, and each strand acts as a template for the synthesis of a new complementary strand. This precise and conservative mechanism ensures genetic continuity between generations of cells. DNA polymerase, the enzyme responsible for DNA replication, not only builds new strands but also performs proofreading, reducing replication errors and maintaining genomic stability.

From replication, molecular biology advances to the central dogma: the transfer of information from DNA to RNA to protein. This flow of information begins with transcription, a process in which RNA polymerase binds to DNA at specific promoter regions and synthesises a matching strand of messenger RNA (mRNA). This mRNA molecule, now carrying the genetic message, exits the nucleus (in eukaryotic cells) and travels to ribosomes, where translation occurs. Here, codons, three-nucleotide sequences on mRNA, are read sequentially to assemble amino acids into polypeptide chains. Transfer RNA (tRNA) plays a vital role in delivering the correct amino acids to the ribosome based on codon-anticodon pairing. As amino acids join through peptide bonds, the resulting polypeptide folds into a functional protein.

Proteins are the ultimate effectors of cellular behaviour. They act as enzymes regulating metabolic reactions, structural components that provide mechanical support, transport proteins that carry essential molecules, receptors that interpret signals from the environment, and antibodies that defend against pathogens. The relationship between protein structure and function is one of the core principles of molecular biology. Even minor genetic mutations that alter amino acid sequences can lead to significant structural changes in proteins, resulting in diseases such as sickle cell anaemia, cystic fibrosis, or certain forms of cancer.

Gene regulation is another essential theme in molecular biology. Cells do not express all of their genes at once; instead, gene expression is tightly controlled to ensure that the right proteins are produced in the right amounts at the right time. In prokaryotes, gene regulation is achieved through operon systems such as the lac operon in Escherichia coli, which controls lactose metabolism based on environmental conditions. In eukaryotes, regulation is more complex and involves epigenetic mechanisms, heritable modifications to DNA that influence gene activity without altering the DNA sequence itself. These include DNA methylation and histone modification, both of which control chromatin structure and accessibility. Epigenetics has reshaped our understanding of heredity, development, and disease susceptibility, demonstrating how environmental factors such as diet, stress, or toxins can influence gene expression across generations.

At the heart of every biological process lies molecular interaction. DNA interacts with proteins such as histones to form chromatin. RNA molecules interact with ribosomes to guide protein synthesis. Enzymes bind substrates with remarkable specificity, catalyzing reactions critical to metabolism. These interactions operate in precise networks, forming molecular pathways that sustain cellular life. Understanding these pathways has been vital in revealing the molecular basis of diseases and developing targeted therapeutic strategies.

The study of molecular biology was accelerated dramatically by advances in experimental techniques. The development of restriction enzymes in the 1970s allowed scientists to cut DNA at specific sequences, giving rise to recombinant DNA technology and the birth of genetic engineering. Restriction enzymes, along with DNA ligase and plasmid vectors, enabled scientists to insert genes into bacteria, plants, and animals, laying the groundwork for modern biotechnology. This innovation led to the production of human insulin using genetically modified bacteria, the first monumental achievement of pharmaceutical biotechnology.

The polymerase chain reaction (PCR), invented by Kary Mullis in 1983, revolutionized molecular biology by making it possible to amplify specific DNA sequences rapidly and precisely. PCR has become indispensable in diagnostics, evolutionary biology, archaeology, and forensic science. It enables the detection of pathogens, the analysis of ancient DNA samples, and the identification of individuals based on genetic profiles.

Following PCR, the sequencing of DNA marked another turning point in molecular biology. Frederick Sanger's chain termination method, developed in 1977, allowed scientists to determine the exact sequence of nucleotides in DNA. By 2003, this technology enabled the completion of the Human Genome Project, which revealed that humans possess approximately 20,000 protein-coding genes—far fewer than previously expected. The project opened new fields such as genomics and bioinformatics, shifting biology from gene-by-gene investigation to whole-genome analysis.

Modern molecular biology has entered the era of precision manipulation of genetic material. CRISPR-Cas9, a gene-editing technology adapted from bacterial immune defense systems, now allows scientists to cut and modify DNA with unprecedented precision and efficiency. This technology holds immense potential for correcting genetic disorders, improving crops, combating infectious diseases, and advancing synthetic biology. Gene drives, based on CRISPR, have even been explored to control mosquito populations and reduce the transmission of malaria.

In parallel, transcriptomics, proteomics, and metabolomics have emerged as powerful disciplines that study RNA transcripts, proteins, and metabolic pathways on a large scale. These 'omics' fields provide a comprehensive view of how genes, proteins, and metabolic reactions interact as systems.

What is life? By Mark Chit Tat

Below is a comment written by Mr Mark Chit Tat following my article on

 "What Is Life? A Dialogue Between Biology, Thermodynamics, and the Breath of God (Part 2)"

He posted his comment 30 mins ago  

But I thought I should make it a small article written by him instead of going into the comment column 

Here is what Mr Mark wrote:

No small dialogue, "a conversation still unfinished," Dr.Lin Ru Wu (林 如 武), your name also speaks aptly of the balance and elements of life. A dialogue of the weightier and "dense"🙂 issues of life, its meaning or purpose, something that is more than what we know or can understand.

After all, it had been "hidden" from us since that day the first Man chose not to eat of that Tree of Life but of the Tree of Knowledge of Good and Evil. So life is somewhat reduced to something like just birth and death, clueless of God's Plan A, so much so that Solomon, the wisest of the ancients lamented that "all is vanity"! But reiterated that "The end of the matter, everything having been heard, fear God and keep His commandments, for this is the entire man.(Eccles 12:8 &13, Rabbi A.J.Rosenberg, Chabad.org)".

However, all that you had shared earnestly and tirelessly in this blog of yours is so propitious to us all and shall remain a legacy accessible and beneficial to many in years to come too.

Jia you! 加油! Dr.Lin Ru Wu (林 如 武)

What Is Life? A Dialogue Between Biology, Thermodynamics, and the Breath of God (Part 2)

  

This is Part 2, a continuation of my thoughts in Part 1 - to give it a more philosophical touch on the definition of life in this link:  

https://scientificlogic.blogspot.com/2025/10/what-is-life-dialogue-between-biology.html

Life is the most familiar and yet the most mysterious phenomenon in the universe. Every second, countless living things awaken, feed, divide, heal, and die; still, the essence that makes them alive remains elusive. The cell biologist defines life in it by its metabolism and replication, the physicist by energy exchange and entropy, the philosopher by consciousness, and the theologian by the breath of God. Each perspective touches part of a greater truth, and together they form a dialogue between science and spirit, a conversation still unfinished.

Biology begins its answer with the cell, that shimmering unit of order in a sea of chaos. Within its fragile membrane, thousands of reactions proceed in exquisite coordination, examples,  proteins fold, DNA copies, ATP fuels every pulse of work. The biologist calls this self-sustaining network “autopoiesis”, the ability of matter to maintain and reproduce itself. Yet even as we map every gene and molecule, something greater seems to hover above the chemistry, like a melody arising from vibrating strings. A living system is not merely a collection of parts; it is dynamic wholeness sustained by information, pattern, and purpose.

Physiology extends the story into the rhythms of energy. Life feeds on disequilibrium. Every heartbeat, every neuron’s spark, depends on gradients, of ions, gases, and potentials. When these gradients flatten, life ceases. From the standpoint of thermodynamics, a living organism is a local rebellion against entropy, continuously importing free energy from its surroundings to keep its inner order intact. Schrödinger, pondering this paradox, wrote that organisms “feed on negative entropy.” We might say more simply that life borrows time from the universe’s long drift toward disorder.

Yet thermodynamics also humbles biology. No creature can outrun the second law forever. Cells age, tissues falter, and entropy reclaims what structure had defied it. Death, in this light, is not a punishment but a physical reconciliation - a return of organized energy to cosmic equilibrium. Still, even as matter decays, information can endure: in offspring, in memory, in the genome that whispers forward through time. Thus physics does not extinguish meaning; it transposes it into new forms.

Philosophy approaches from another side. The vitalists once argued that living beings possess a special essence, a “vital spark” beyond chemistry. Modern science dismissed that notion when it learned to synthesize organic compounds from inorganic ones, yet the intuition persists that something non-mechanical animates the living. Today, some philosophers of mind echo that intuition when they ask whether consciousness can emerge from matter alone. Is awareness merely an algorithm of neurons, or is it the universe becoming self-aware through us? Between mechanism and mystery lies the field where wonder still grows.

Across cultures, humanity has never been content with a purely mechanical account of life. Ancient Egyptians spoke of the ka, the life-force breathed into each person. In Hindu thought, prana is the cosmic breath that circulates through all beings. Chinese philosophy calls it qi, the flowing energy of heaven and earth. The Hebrew Scriptures describe creation with a similar image: “The LORD God formed man of the dust of the ground, and breathed into his nostrils the breath of life; and man became a living soul” (Genesis 2:7). In this simple verse, dust and breath meet, the physical and the divine entwined.

The biological breath and the biblical breath, though different in language, describe the same marvel: that matter can host awareness, desire, and compassion. Oxygen enters the lungs, diffuses into blood, fuels the mitochondria that power thought and love. But breath is more than gas exchange; it is the symbol of participation, the rhythmic reminder that life is shared. Each inhalation draws in the world; each exhalation returns a part of ourselves. When the final breath leaves, the body remains, but the pattern - the harmony of exchanges- is gone.

From a thermodynamic viewpoint, this cessation is simply the collapse of gradients; from a spiritual viewpoint, it is the release of spirit. Both can be true within their frames. The scientist observes the dispersal of energy; the believer perceives a passage. Between them stands the mystery that language can barely hold.

If we compare definitions, science emphasizes organization, metabolism, growth, adaptation, and reproduction. Theology speaks of soul, purpose, and divine image. Yet neither definition alone suffices. An artificial cell might one day mimic every metabolic step, but would it feel alive? A theologian might affirm that all breath comes from God, but must also acknowledge the physical processes that sustain it. The two accounts do not cancel each other; they complete one another like stereo channels revealing depth.

Death, therefore, is not the antithesis of life but part of its continuity. The atoms that once formed a heartbeat soon nourish soil, plankton, or star-dust anew. Energy changes costume but not existence. As Ecclesiastes reminds us, “Then shall the dust return to the earth as it was: and the spirit shall return unto God who gave it” (Ecclesiastes 12:7). Even in decay, life’s story expands.

Culturally, people have translated this intuition into rituals and ethics. Funerary rites, from the pyramids to modern memorials, affirm that life’s essence deserves reverence. Philosophers from Aristotle to Bergson spoke of entelechy or élan vital, a striving toward fulfillment that shapes every organism. In modern biology, this striving becomes the language of homeostasis and feedback loops, systems perpetually adjusting to preserve integrity. Whether we call it purpose or regulation, the tendency is the same: life seeks to remain itself.

The dialogue between biology and theology grows most intimate when we ask not what life is, but why it is. Evolution explains the mechanisms of adaptation, yet it cannot alone address why the universe gives rise to beings capable of asking questions. Physics can chart the energy exchanges of a heartbeat, yet it cannot explain why music can quicken it. Meaning itself seems to bloom in the interstices between data and devotion.

In recent decades, the science of complexity has offered a bridge. From chaos theory to systems biology, we learn that self-organization can arise spontaneously from simple rules, that feedback can produce order from noise. But even this elegant mathematics evokes wonder: why should the laws of nature permit such harmony at all? The more we decode the machinery of life, the more its existence feels like a gift rather than an accident.

Perhaps that is why poets and prophets speak of life as light. “In Him was life; and the life was the light of men” (John 1:4). Light and life are both acts of transformation, energy becoming visibility, matter becoming awareness. Thermodynamics tells us that every photon absorbed by a leaf becomes sugar, and every sugar molecule can become thought. Scripture tells us that divine light enlightens every human being. The metaphors converge: to live is to shine.

From a public-health perspective, recognizing this unity carries practical wisdom. To care for life is to respect its delicate balance of energy and purpose - nutrition, rest, love, and community all sustain the thermodynamic miracle within us. Pollution, exploitation, and neglect are not merely ethical failures; they are violations of the very principles that keep systems alive. The stewardship of life therefore extends from cell biology to planetary ecology.

And yet, amid this grandeur, life remains intimate. It begins in the invisible union of molecules, grows in the warmth of a mother’s body, learns to walk, to hope, to forgive. Each personal story is a local expression of the universal drive to persist, to connect, to transcend. When we say someone has “lost the will to live,” we are describing not only biochemical exhaustion but the dimming of meaning. Spirit and physiology intertwine until the last pulse.

So, what is life? It is a self-maintaining pattern of matter and energy, open to the flow of the universe, able to transform and be transformed. It is the dance between entropy and information, between dust and breath. It is the signature of the cosmos learning to love through conscious beings. To describe it purely in formulas is to know its skeleton; to encounter it with reverence is to touch its soul.

In my own conviction as simple lim ju boo by name, or by my Chinese name -  lim ru wu, (林 如 武)  after following both microscopes and scriptures, I believe life is neither random chemistry nor magic alone. It is the language through which the universe, and perhaps its Creator - speaks coherence into chaos. Every cell, every heartbeat, every act of compassion is a syllable in that divine dialogue. When science measures, it listens to the grammar; when faith worships, it hears the music. Both are hearing the same voice.

And when the breath finally leaves, I imagine it not as extinction but translation. The molecules return to soil and star; the pattern returns to the Source that first uttered it. Between the physicist’s entropy and the psalmist’s praise, a single truth gleams: “I will praise Thee; for I am fearfully and wonderfully made” (Psalm 139:14). Life is that wonder made visible.

 

References

1. Schrödinger E. What Is Life? The Physical Aspect of the Living Cell. Cambridge University Press, 1944.

2. Prigogine I., Stengers I. Order out of Chaos: Man’s New Dialogue with Nature. Bantam, 1984.

3. Margulis L., Sagan D. What Is Life? University of California Press, 1995.

4. Kauffman S. A World Beyond Physics: The Emergence and Evolution of Life. Oxford University Press, 2019.

5. Ecclesiastes 12:7 (King James Version).

6. Genesis 2:7 (King James Version).

7. John 1:4 (King James Version).

8. Psalm 139:14 (King James Version).

9. Bergson H. Creative Evolution. Macmillan, 1911.

10. Capra F. The Systems View of Life. Cambridge University Press, 2014.

My next 3 articles spread out over next two weeks, shall be on Molecular Biology, namely: 

1. Molecular Biology: The Language of Life and Its Transformative Power Across Science,  Medicine to Forensic Investigations 

2.  Molecular Biology in Medicine: From Genes to Therapeutics  - Dedicated to the advancement of human health through molecular insight and scientific compassion.

3. Molecular Biology in Forensic Science: Unveiling Truth Through DNA in Crime Investigation with a number of examples on high profile cases in Malaysia  

 

What Is Life? A Dialogue Between Biology, Thermodynamics, and the Breath of God (Part 1)

 

Anne Carol commented on "What Happens to the Soul of a Clinically Dead Person in Coma?"

She commented:

"Fascinating article as always. Can you tell us more about the mystery of life and death? How would you define life, and what happens when it dies? We have always wondered on this question for an answer.

Can you tell us more on this, Dr Lim?" 

Here's an extension of my thoughts for Anne Carol  in blue: 

Presently, we have no definition for life. The acronym for living things is often given as MRS GREN to mean Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion, and Nutrition.

But these are defining the characteristics of something that is  living,  but it is not the definition of life itself. So  what is the true definition of life? Is it some biological entity, some life energy, life force, spiritual life or what  resides inside a physical body, and what  happens when it leaves the body? The direct answer is -  the body dies?
The true definition of life is a complex and debated topic, but scientifically, life is defined by a set of characteristics, such as those in the MRS GREN acronym, that describe how an organism functions, rather than a separate "life force".  There is no evidence in the eyes of science for a non-biological "life energy" leaving the body at death; rather, death is the cessation of these biological processes.
Biological definition of life is a process, not a thing.  Science defines life by its functions, such as metabolism, growth, and reproduction, rather than a singular entity. These key characteristics is a useful starting point, but a more comprehensive list of non-entity characteristics that define life is needed such as life or vital force 

On the existence of "life force" or "spiritual life", unfortunately currently we have no scientific basis for this. The idea of a non-biological "life force" or "life energy" is a concept from spirituality and philosophy, not biology. As far a s science is concerned, death is the end of a biological function. When a body dies, it is because the complex biological processes that sustain it have permanently stopped, not because a non-physical entity has left the body - at least this is what science describes. Science defines life through observable and measurable biological processes, not through a spiritual or metaphysical concept. While MRS GREN is helpful, a complete understanding of what makes something becoming alive is more than than just describing the characteristics of life. 

The cessation of these biological processes is what defines death according to science, not the departure of a separate life force as religion sees it.  
Since science cannot define exactly what is life, except define its characteristics as something living, can we give the definition as the breath of God?  This question brings two distinct ways of understanding the world - the scientific and the theological, into conversation. Science describes how living things function, reproduce, and evolve by observing their characteristics.
Religion explains the metaphysical source of life, offering a divine or spiritual explanation for its origin and essence. Therefore, one framework cannot be directly substituted for the other.
Science does not attempt to define the ultimate "essence" of life. Instead, it uses a set of observed characteristics to classify things as living, non-living, or dead. The characteristics of life is just a list of working models seen in living things. It is not the definition of life itself. Moreover, some entities like viruses challenge this criteria highlights that life is a complex process that resists a simple, catch-all definition. 

The theological perspective ("Breath of God"): 
The concept of the "Breath of God" is a religious explanation for the origin of life, not a description of its biological functions. In the Bible on Genesis, God is described as breathing the "breath of life" into humanity, an intimate act that brings a physical form to life. This theological idea addresses the ultimate source of existence rather than the biological mechanisms through which it is sustained. It is a different realm of inquiry. Our question conflates a scientific model with a theological explanation, which occupy different realms of thought:
Science answers "how?" It provides mechanistic, evidence-based answers for how biological systems operate. Science cannot explain everything. It does not mean that only when something we can see, touch, detect and measure, are real and exist - the rest all not real and does not exist? It is so clear and real we see life creeping, crawling and flying everywhere on earth, and just because we  cannot understand or define what they are, and why they are living, and what makes them alive,  they are not science, and not real? But religion has the answer, and philosophy answers "why?" These fields explore questions of ultimate purpose, origin, and meaning, often outside the scope of scientific inquiry. The abundance of life presence on earth challenge of a single definition
The attempt to force a single, universal definition of life is not only difficult for science but also problematic in a philosophical context. As a 2024 paper wrote, there is no comprehensive scientific definition that perfectly separates living from non-living things, in part because life is a continuous, evolving process rather than a discrete, static category.

Therefore, equating the characteristics listed in the MRS GREN acronym with the "breath of God" mixes a functional, descriptive model with a spiritual, metaphysical explanation. The two ideas serve different purposes and offer different types of understanding. 

The entity that gives a body life is known as a "vital force," "spirit," or "soul," but there is no scientific consensus on what it is, and it cannot be detected or measured by current scientific methods. From a biological and scientific perspective, life is the result of a complex interplay of chemical and biological processes, and death occurs when these processes cease. Different cultural and spiritual beliefs attribute death to the departure of the soul or spirit from the body.

But what makes a body alive? From a scientific perspective,  life is a property of organized biological systems, a result of cellular and biochemical processes, not a single "entity" or "force".
But from a spiritual / cultural perspective, life is often attributed to a "vital force," "spirit," or "soul" that resides within the body and animates it. The specific beliefs about this entity vary across cultures and religions.

Then why does death occur? From the scientific perspective, death is the irreversible cessation of all biological functions that sustain a living organism. When the body's systems, such as the brain, heart, and lungs, stop functioning, the organism dies.

From the spiritual perspective, death is considered the point at which this non-physical "soul" or "spirit" leaves the physical body, which is why the body can no longer live.

Then many have continued to ask for ages can we detect or measure this living force? In the eyes of science, the answer is no. There is no scientific evidence or method for detecting or measuring a "vital force," "soul," or "spirit" in this context. Science relies on empirical evidence that can be observed and tested, and these concepts are beyond its current scope. But from the spiritual perspective, those who believe in a soul or spirit do not see it as something that can be measured by physical instruments, but rather something that is experienced or known through faith or spiritual intuition.

This brings us back to the "true" definition of life which is a complex and debated topic, but scientifically, life is defined by a set of characteristics that describe how an organism functions, rather than a separate "life force". Currently we have no evidence for a non-biological "life energy" leaving the body at death; rather, death is the cessation of these biological processes. Biological definition of life is, it is a process, not a thing. 

Science defines life by its functions.  But the idea of a non-biological "life force" or "life energy" is beyond science, a concept from spirituality and philosophy, not biology.  But others will ask the scientist why does the body finally dies? In the eyes of a scientist, death is the end of biological function. 

When a body dies, it is because the complex biological processes that sustain it have permanently stopped, not because a non-physical entity has left the body. 

When a body dies, biological processes begin, including the cessation of breathing, circulation, and brain activity, followed by cooling and decomposition,  

The question of what happens to "life" or consciousness is a matter of faith and philosophy, with different beliefs including an afterlife, reincarnation, or the cessation of consciousness at death. Science currently has no evidence for the continuation of consciousness after death, attributing near-death experiences to the brain shutting down. In death there are physical changes to the body. There is initial shutdown when  breathing, heart, and brain activity cease. Blood circulation stops, and all the body's systems shut down. 

The body temperature drops until it reaches the ambient temperature. 

Decomposition begins when 

bacteria begin to break down the body's tissues. Enzymes digest cells, and bacteria in the intestines and other tissues start digesting the body, which can cause bloating and gas. There is 

structural collapse when over time, the soft tissues will disintegrate, leaving behind a skeleton that will eventually crumble. That's from a biological and chemical stand-point. 

From a physics, and thermodynamics 

standpoint, death is when a body stops maintaining its organized state and its energy disperses into the surroundings.  Life maintains low entropy by constantly consuming energy to organize its matter, but death is a point where this process ends, and the body's energy, stored in chemical bonds and mass, dissipates as heat and is broken down through decomposition, increasing the overall disorder (entropy) of the universe. The body's energy dissipates but the energy is conserved. 

The first law of thermodynamics states that energy cannot be created or destroyed, only transferred or changed in form. The energy in the body doesn't disappear; it is released. 

The body's internal heat, produced by metabolism, transfers to the colder environment, causing the body to cool down to ambient temperature. This is a major part of why medical examiners can estimate time of death based on body temperature. 

The energy stored in the body's chemical bonds (like those in sugars, fats, and proteins) is released as molecules break down through decomposition. This dispersed energy is then available to be absorbed by the environment, such as by decomposers like bacteria and insects, or eventually to be incorporated into new life forms. 

Life is low entropy - 

Living organisms are highly organized systems that maintain low entropy by using energy to stay structured and functional. 

Death is high entropy -  

The second law of thermodynamics states that entropy (disorder) in a closed system always increases over time. Death is the point where the body's ability to fight this natural tendency for disorder ends. 

Decomposition is the result: 

Decomposition is the final thermodynamic process where the body's organized matter breaks down into simpler, less organized components, increasing the overall entropy of the universe.

Beliefs about "life" or consciousness in religions and atheists views  are: 

Afterlife: 

Many religions, including Christianity, Islam, and Judaism believe the soul or spirit continues to exist in another world, such as heaven and hell, or a spiritual realm. 

Reincarnation: 

Religions like Hinduism and some others believe the soul is reborn into a new physical body after death, continuing a cycle of life and death. 

 Enlightenment:

Some Buddhist beliefs suggest that it is possible to escape the cycle of death and rebirth through spiritual enlightenment. 

Some people believe that consciousness is a product of the brain, and that when the brain dies, consciousness simply stops, with no life after death. 

Near-death experiences like seeing a bright light or feeling peace during a near-death experience may be caused by changes in the brain to be able to 'see' as it shuts down but this is hotly disputed, because there were people blind from birth who could not describe how the physical world looks like, but when the return from death they could describe clearly what the physical world looks like though still blind when they returned from death. Moreover changes in the brain chemistry during death do not provide evidence of consciousness continuing after death, according to Verywell Health. 

In conclusion for a scientist, science defines life through observable and measurable biological processes, not through a spiritual or metaphysical concept.  The cessation of these biological processes is what defines death, but in the eyes of science it is not the departure of a separate life for. But in the eyes of religion, especially in Christianity, life is the breath of God  that is not meant to be measures or detected, and it shall go back to where it belonged 

And the LORD God formed man of the dust of the ground, and breathed into his nostrils the breath of life; and man became a living soul (Genesis 2:7).The phrase "the soul returns to where it came" is a well-known line from Ecclesiastes 12:7 in the Bible, which states that after death, the body returns to the earth as  star  dusts from another world brought here through a supernova explosion, and the "spirit returns to God who gave it" 

In many traditions, this signifies a return to a divine source or a state of being beyond the physical world. Other belief systems describe different outcomes, such as reincarnation or a cycle of life, death, and rebirth. 

Unlike other scientists, this is what I strongly believe.  

(I shall write more on this subject in a more philosophical tone in Part 2)