Lesson 7: Theories About the Origin of Life PDF

Lesson 7 (Earth and Life) THEORIES ABOUT THE ORIGIN OF LIFE LIFE-BIO STRUGGLE AND STUDY- PAIN ARE THE LOGOS SOIL OF LIFE  Precambrian Sponge Nautilus How did 760 million years old over 50...

Lesson 7 (Earth and Life) THEORIES ABOUT THE ORIGIN OF LIFE LIFE-BIO STRUGGLE AND STUDY- PAIN ARE THE LOGOS SOIL OF LIFE  Precambrian Sponge Nautilus How did 760 million years old over 500 million years old as primitive a species organisms SURVIVE on earth? Coelenterates (Jellyfish) Horseshoe Crab 500 million years old called living fossil, remaining virtually unchanged 445 million years old.  How did primitive organisms STILL live on earth? 200 million years 235 million years  Learn about it! 1. Theory of Spontaneous Generation (Origin of Idea) ❖ This theory was assumed to have originated from Anaximander, a Greek philosopher in the 6th century BCE. Other philosophers, including Aristotle, adapted and expanded Anaximander’s idea. ❖ Aristotle explained in his writing, The History of Animals that was written in 350 BCE, that some organisms appeared from inanimate objects spontaneously. ❖ The theory of spontaneous generation described that life comes from lifeless or nonliving material through a mysterious process. (Abiogenesis)  Learn about CHALLENGES OF THISit! THEORY ❖ In order to disprove the abiogenesis concept of the spontaneous generation theory, Francesco Redi (1668) challenged the idea by using the concept that maggots came from rotting meat. Spontaneous generation  Learn about CHALLENGES OF THISit! THEORY ❖ By contrast, John Needham (1745) conducted an experiment on boiled broths to support spontaneous generation theory. He believed that boiling kills microorganisms in the broth. ❖ In 1768, Lazzaro Spallanzani made some modifications on Needham’s experiment by excluding the possibility of contamination factor prior sealing Spontaneous generation CHALLENGES OF THIS Learn about it! THEORY- FINALLY ❖ 1859, a French scientist, Louis Pasteur made an experiment to totally disprove the spontaneous generation theory. ❖ In his experiment, Pasteur boiled a meat broth in a goose-like flask having a long curved neck. ❖ He explained that the bend in the neck prevented particles from reaching the meat broth and still allowed free air to flow. Spontaneous generation  Learn about it! 2. Theory of Panspermia This states that life on Earth was seeded from a celestial source. This theory was proposed by the astronomer Fred Hoyle in the 19th century. It states that life on Earth was seeded from a celestial source. The theory of panspermia is also called exogenesis, as some of its hypotheses suggested that building blocks of life came from another planet. These include comets colliding the Earth and depositing living cells or the precursors of life, and aliens making life-essential materials in a laboratory. 3. Primordial Soup Learn about it! Theory According to this theory, life started in a primordial soup of organic molecules. According to the primordial soup theory proposed by Alexander Oparin and John Haldane, life started in a primordial soup of organic molecules. This theory explains how catalysts for non-living things became living cells from chemical compounds abundant on early Earth. The primordial soup theory  Learn about it! MILLER-UREY EXPERIMENT In 1950, Stanley Miller and Harold Urey at the University of Chicago: ❖ Putting ocean water in a glass container, the gases hydrogen, methane, and ammonia (atmosphere) and an electric arc (lightning) ❖ Letting the reaction run for a week, they analyzed the content of the reaction vessel  Learn about it! MILLER-UREY EXPERIMENT In 1950, Stanley Miller and Harold Urey at the University of Chicago: ❖ They found biological molecules, amino acids, fatty acids, and urea. ❖ IN 1959, this experiment was considered as a great triumph in Darwinian Centennial Celebration “Evolution does not attempt to explain the origin of life. It simply a history of the process of life. With the secret cause of life evolution has nothing to do. A man therefore, maybe a materialistic evolutionist; that is, he may believe that the cause is some single unintelligent impersonal force or he may believe that the cause is a wise and beneficent God.” Author: Lyman Abbott Key Points Life science is a collection of disciplines that 1 tackle living things. 2 An individual living creature is termed as an organism. All living organisms are capable of reproduction, growth and development, adaptation, movement, 3 exhibiting metabolism, and maintaining homeostasis.  Bibliography Aleksandr Ivanovich Oparin. 2003.The Origin of Life. Massachusetts: Courier Corporation. Matthew S. Dodd, Dominic Papineau, Tor Grenne, John F. Slack, Martin Rittner, Franco Pirajno, Jonathan O’Neil & Crispin T. S. Little. 2017. Evidence for early life in Earth’s oldest hydrothermal vent precipitates. Nature: 543, pages 60–64. Larry L. Hench. 2001. Science, Faith, and Ethics.Singapore: World Scientific. Lisa A. Shiel. 2009. The Evolution Conspiracy, Vol 1: Exposing Life’s Inexplicable Origins and the Cult of Darwin.Texas: Jacobsville Books. Sandra Alters. 2000.Biology: Understanding Life. Massachusetts: Jones & Bartlett Learning. Shri Hemant Roy. 2005.Comprehensive MCQs in Biology.New Delhi: Golden Bells. Rakesh Kumar Rastogi. 2007. Concepts of Biology XII. New Delhi: Rastogi Publications.  Photo Credits Peter J. Russell, Paul E Hertz, and Beverly McMillan. 2016. Biology: The Dynamic Science, Boston: Cengage Learning. Jason P. Schrum, Ting F. Zhu, and Jack W. Szostak. 2010. The Origins of Cellular Life. Cold Spring Harbor Perspectives Biology.