WHY IS THE DEFINITION OF LIFE AND LIFE’S ORIGINS ON EARTH IMPORTANT IN EXTRATERRESTRIAL RESEARCH Jan Jędryszek 1;78703924449250650000000000000 000000000000000000000000000000 000000000000000000000000000000 000000000000000000000000000000 000000000000000000000000000000 000000000000000000000000000000 000000000000000000000000000000 000000000000000000000000000000 0 1. Introduction Plan 2. Life – Is a definition of a “living system” possible? – Life’s origins? 3. Looking for life 4. Thompson Jr. – Future findings and results – Advantages The 2nd Law & Entropy ENTROPY - . "a measure of disorder or randomness in a closed system.“ -The American Heritage Dictionary . "mixedupness." -J. Willard Gibbs, theoretical physicist Can you reduce entropy? • The total entropy of system A can not decrease without increasing the entropy of system B. • Hence, in a system isolated from its environment, the entropy of that system will tend not to decrease. Humans don’t dissolve. Are we isolated systems? We are NOT Gibbs Free Energy G = H − TS • H - enthalpy (joules) • T - temperature (kelvins) • S - entropy (joule per kelvin) ∆G negative = reaction can occur spontaneously. +5.5 kcal/mole. Glucose Fructose -7.3 kcal/mole ATP ADP P ATP ATP P ADP ATP P Sucrose P ADP ATP -1.8 kcal/mole -7.3 kcal/mole. (the reaction will occur +5.5 kcal/ mole spontaneously. ) P Sucrose P ADP Gibbs Free Energy is the basic principle behind all enzymatic action in biological organisms Entropy is NOT an obstacle for life. Abiogenesis The natural process of life arising from non- living matter. Life? • Life - The ability to grow, change, etc. that Life separates plants and animals from things like water or rocks. • Life is not a “thing” • It’s a process • Millions of biochemical reactions in every single cell in our bodies. • Eg: Bacteria are a single cell that, just like us, have its own DNA, and can synthesize its own proteins, replicate, breathe, eat • A virus cannot replicate by itself – it needs a host cell in which it can insert its genetic material – enslave its host, forcing it to create copies of the virus. • Are viruses alive at all? • Better question – what can we consider as a “marker” of life in a virus? – Not the protein capsid – Not the DNA.. – ..but the information that it’s DNA carries. Life & Entropy • Claude Shannon; information is negative entropy. (Information theory) • It’s the very opposite of disorder. • Information is the basis of life – it doesn’t matter how this information is encoded. DNA, RNA, amino acid chains, etc. • Claude Shannon; information is negative Life & Entropy entropy. (Information theory) • It’s the very opposite of disorder. “Max Entropy/• MinInformation Info” is the basis of life – it doesn’t matter how this information is encoded. DNA, RNA, amino acid chains, etc. ↓Entropy/ Info↑ “Minimal Entropy/ Maximum Information” (H or T) 푝ℎ − probability of Heads 푝푡 − 푝푟표푏푎푏푖푙푖푡푦 표푓 푇푎푖푙푠 log2 푝 − (2 푏푒푐푎푢푠푒 2 푝표푠푠푖푏푙푒 푟푒푠푢푙푡푠; 퐻푒푎푑푠 표푟 푇푎푖푙푠) −푝ℎ log2 푝ℎ − 푝푡 log2 푝푡 = 1 1 1 1 1 1 1 1 − log − log = − × −1 − × −1 = + = 1 2 2 2 2 2 2 2 2 2 2 Resulting in 1 bit of information. time ATP -1.8 kcal/mole -7.3 kcal/mole. (the reaction will occur +5.5 kcal/ mole spontaneously. ) P Sucrose P ADP “Controlled Descent” -Energy is being dispersed all the time – Entropy rises. -The living “know” how to use it to their advantage. • In order to find life, we need to understand the definition and the source, the reason of life. • We need to understand how life came to exist. • But alien life doesn’t have to be similar to Earth-life. The panspermia hypothesis suggests that life originated from a different place then Earth, and the first life forms were brought to earth via meteor. Earth Climate Martian Climate Europa’s Climate Enceladus 40% volume ocean Salt content similar to Earth Ice at South Pole 5 km thick Saturns Gravity is NOT enough to explain how Enceladus stays warm (thin ice – traps less heat) Heat production at core? Complex compounds found in its jets Europa Ceres Mars • 1500 years? – Drake equation – Mediocrity Principle (we are not unique) • Graveyard – Habitle zone does not mean life – Early habitle conditions may be unstable – Eg. Earth; the earliest metabolites started modyfing greenhouse gases; methane, carbon di oxite, hydrogen, water • Armando Azua-Bustos and Cristian Vega-Martínez • Quantify the degree of entropy difference (and thus, their structural complexity) of living processes (e.g. plant growing patterns) as entities separate from similar abiotic surroundings. • This approach may allow possible detection of unknown forms of life based on nothing more than entropy differentials of complementary datasets. • Future explorations in the solar system, like Mars or Titan, may incorporate this concept in their mission planning in order to detect potential endemic lifeforms. James Webb • Io, Enceladus, Europa.. Thompson • Bubble scrubbing • Gel • Fractal complexity analysis - detecting life that we Thompson 1 don’t even suspect exists using the patterns it creates when it grows. • - Detecting life by looking for a heat process emitting a Thompson 2 precise wavelength, instead of looking for bio- signatures: it looks for the process we recognize as “life”, not its building blocks (which can be very different.) Nuclear magnetic resonance spectroscopy - Detecting the Thompson 3 structure and dynamics of the molecule: better understanding of the processes beyond earth. – Future findings and results Positive results – Hydrothermal vents necessary for life formation? o Similar – Panspermia? o Different – the universe is full of life Negative results– patches of water on land necessary for life formation? No need to land o No risk of containment by earth- brought organisms. o No lander – saves money. Offers the possibility to find alien life we did not imagine even exists Offers the possibility to find molecules and processes that could lead us to better understand abiogenesis and how we came into existence. By the way….. The simplest theorized self-replicating peptide is only 32 amino acids long. The probability of it forming randomly, in sequential trials, is approximately 1 in 1040 • Life is 78703924449250650000000000000 26169,541 00000000000000000000000000000 = 00000000000000000000000000000 1040 00000000000000000000000000000 00000000000000000000000000000 00000000000000000000000000000 00000000000000000000000000 times more likely to come into existence than a monkey typing “Hamlet”. Bibliography • “The story of Earth”, 2012– Robert M.Hazen • “Dylematy Ewolucji”, 2016 – Michal Heller, Jozef Zycinski • “The Mystery of Life’s origin”, 1984 • “Evolution as Entropy”, 1994 - Daniel R. Brooks and E. O. Wiley • "The Probability and Origin of Life“, 1984- Russell Doolittle • “Statistical physics of self-replication”, 2013 - Jeremy L. England • “ The potential for detecting ‘life as we don’t know it’ by fractal complexity analysis”, 2013 - Armando Azua-Bustos and Cristian Vega-Martínez •.
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