Dr Irengbam Mohendra Singh
Human history is loaded with mythologies. I remember one that I heard during my childhood. In Hindu mythology, the Earth was supported on the back of a giant turtle Kurma, the second incarnation of Vishnu, during the churning of the Ocean of Milk between the gods and demons (asuras). Science is gradually opening our eyes.
It was only in the past 40 years, scientists found unicellular bacteria with nuclei (eukaryotes) from which humans evolved. These bacteria evolved from another species known as archaea. Prof Ettema, a microbiologist at Uppsala University in Sweden, discovered in 2015, that a species of archaea most closely related to eukaryotes, lived in the seafloor, two miles below the surface of the Arctic Ocean.
Ettema established the DNA from this particular species was from a lineage of archaea, unlike any previously found. It’s thus possible that other more ancient relatives might be waiting to be discovered. While waiting for our origin, scientists have uncovered mitochondria that give us life or death.
Mitochondria synthesise the energy molecules ATP (Adenosine triphosphate), that give power to cells in our body to keep us alive, by running a range of biological processes. Scientists from the National Institute of Health, Maryland, US, have found that mitochondria create many essentials of life , such as the iron compound that allows red blood cells to transport oxygen to tissues of our body, and the steroid hormones including cortisol, oestrogen, progesterone and testosterone, without which there can’t be life.
Mitochondria can also switch off our life, by shutting off the energy supply to cells, and producing death-promoting proteins, as a response to an overwhelming stress, such as a stroke or heart attack, says Vamsi Mootha of Harvard Medical School, US. In a new research, Peter Kramer and Paola Bressan at Universita di Padova in Italy, wrote: “Our mind can only work as well as our mitochondria. Our brain can’t perform its functions without energy supplied by mitochondria.”
The idea of a life-giving force or the soul, has been with us since humans began to think. And for most of human history, soul was a special kind of spirit that animated the living.
In the 19th century, the theory of ‘vitalism’ was espoused, but it was soon discarded when it was known that organisms are made from the same six chemical elements as in inanimate things, ie atoms and molecules of oxygen, hydrogen, carbon, nitrogen, calcium and phosphorous.
In the 18th century, doctors studied the workings of human body from public dissections of dead bodies, such as at ‘The Company of Surgeons in England’, which later became The Royal College of Surgeons. But no magical ingredient like the soul that would support life, was ever found. Then experimentation on reviving corpses began in the 19th century. It was the time when religion was losing some of its hold, and people in the West, were trying to understand the beginning of life. Many believed then, electricity was the vital force that animates a human being.
In November 1818, a Scottish chemist performed a research demonstration of what electricity could do to a corpse, in front of many students, anatomists, and doctors at the University of Glasgow. He connected two metallic rods charged with high voltage from voltaic batteries to the body of a corpse, in just a few minutes after he hanged to death by his neck. The crowd watched with awe as the body convulsed and twitched. Many people thought the body had come to life and died again.
An Austrian physicist, Erwin Schrodinger, who fled Nazi Germany and ended up in Dublin, gave lectures on ‘what is life’, which was published in a book in 1944. He is best known for his work on Quantum Theory, for which he shared Nobel Prize in Physics with Paul Dirac in 1933. He said life is a physical process by which energy is transformed from one form to another. He asked the question, how did the first, relatively simple biological molecules gradually ratchet up their complexity?
Schrodinger answered himself. There is memory in the system. Once a complex process has emerged, it need not be continually invented. An extraordinary molecule must be unusually stable and be able to pass information from one generation to the next. That’s what Watson and Crick discovered in 1953, as the double helix of DNA, though in the 20th century, a few scientists hypothesised life began from the ‘RNA world’. That is, RNA kick-started life on Earth, with DNA coming along.
Soul is the energy of living. Energy is a mathematical concept, a quantifiable notion. Heat is not energy. It’s energy in transit. Scientists say that the immense primordial energy created after the Big Bang was the cauldron from which all life arose. This energy is indestructible. It’s passed on to produce more and more complicated cells that resulted to the ultimate evolution of humans.
When I was at St Xavier’s college in Bombay, our chemistry professor told the story of how a scientist tried to find out whether hot or cold energy is equally transferable. He swung a red-hot iron rod towards his wife, who ran around in the room. Then unnoticed by his wife, he picked up a lump of ice and touched his wife with it. His wife was hysterical, saying “I’m burnt. I’m Burnt”. That showed that energy is transferable. The energy from the cold ice when transferred to her, the unpleasant feeling she had was the same as the heat from the rod.
I often wondered what generated the first life on earth 4 billion years ago! Now I believe it was the ATP molecule. But where did the energy come from to make the first ATP molecule? Peter Mitchell (1920-1992), a British biochemist, who was awarded 1978 Nobel Prize for chemistry, demonstrated that ATP synthesis is powered by proton gradients (see below) that exist in nature. The process is known as chemiosmosis and is now known in atomic detail. This was one of the most counterintuitive discoveries in biology. Mitochondrial DNA is solely inherited from mother. Mitochondria convert energy from food molecules into a form that cells can use ie ATP, known as The energy currency of life.
Mitchell’s hypothesis of ATP is synthesis in mitochondria, as a result of protein transfer, creating a concentration gradient of protons, has been proven true by the discovery of ATP synthase, a protein in the mitochondrial membrane that uses the potential energy of the electrochemical gradient to make ATP.
This is the tendency of substances to diffuse from regions of higher concentration to those of lower concentration. His theory was substantiated by Andre Jagendorf, a biologist at the University of Illinois, who discovered that a pH difference across the thylakoid, a membrane-bound compartment in the chloroplast of green plants, results in ATP synthesis in plants by photosynthesis.
Photosynthesis creates glucose with sun’s energy that is stored in it, as chemical bonds (attraction between atoms or molecules that enables the formation of compounds). Living things get their glucose and other carbohydrates from plants that they eat as food. In the mitochondria, they are broken by oxygen (cellular respiration), to release energy and make ATP.
All living things, from the microscopic bacteria to the complex human body require this energy-transporting molecule ATP to survive. ATP stores energy in a form that can be used by organisms.
Every living organism that’s capable of doing something, such as movements of muscles, contains ATP ie life’s energy or the soul. Mitochondria generate heat in our body and waste products of carbon dioxide, water, and corrosive compounds known as ‘free radicals’ that degrade cells as well the mitochondria themselves.
ATP molecule is made of Adenosine and three phosphate groups. Adenosine is a nucleotide found widely in nature, known also as ‘molecular energy’, as it is able to store and transport chemical energy within cells. Energy released from ATP molecule is also used by ADP (one adenosine and two phosphate groups) to change it back to ATP. There are about 50g of ATP in our bodies, weighing an average of 70g, which is constantly moving out of mitochondria to power cellular activity and then back again as ADP to change into ATP. Human body recycles its own body weight equivalent in ATP each day ie on average 2788 times .
As Richard Feynman (1918-1988), the most famous American theoretical physicist explains: “The law of conservation of energy is a most abstract idea, because it is a mathematical principle. We can calculate some number and when we finish watching nature go through her tricks and calculate the number again, it is the same.”
So, the mitochondrial energy like the soul is indestructible. The ATP in mitochondria, which flows unchanged from one from to another during our long evolution, must be like the soul. In Gita, Krishna says to Arjuna: “Just as soul acquires a childhood body, a youth, and an old body during this life, similarly the soul acquires another body after death. This should not delude the wise (2.13). Just as the air takes aroma away from the flower; similarly, the individual soul takes the six sensory faculties from the physical body it casts off during death to the new physical body it acquires in reincarnation,” (15.08).
The writer is based in the UK