Cheltenham HS

Life 
 
 A cereal, a board game, Escherichia Coli, if life is 
 all of these things, how can it be defined? When I 
 hear the word “life”, the first thing I think of is 
 vivacity, energy, constant movement.... but it’s more. 
 Life, is almost everything. If there wasn’t life, 
 nothing would be known, nothing would be seen, nothing 
 would be heard, there would just be a collection of 
 elements dispersed throughout the universe. So if 
 that is what it would be like without life, what is 
 it like with life? Patterns (like DNA and RNA), 
 information, machinery (technology), feedback (reactions 
 to stimuli), communities, and evolution, are all parts 
 of life. At times, life can be caustic, there are 
 diseases, and wars that arise because of conflicts, 
 and prejudice. However, even the bad things in life 
 are required for us to learn from and then develop. 
 
 The way you can tell if something is living, is by these 
 similarities, all living things, are composed of one or 
 more cells, use energy, sustain homeostasis, change, are 
 built according to genetic instructions, are complex, 
 reproduce, respond to incitement, and lastly, have a 
 metabolism. These are scientific characteristics of 
 life, but I think that learning, teaching, observing, 
 and having emotions are also what makes 
 something animate. A religious point of view about 
 living things is all sophisticated living things 
 believe in some god or spiritual being, and all life 
 forms are loved by that spiritual being.
 
 As well as the different opinions about what life is, 
 there are also disagreements when it comes to how life 
 originated. 3.8 billion years ago, the first life forms 
 evolved on Earth. The way that it occurred is 
 debatable. I tend to believe that life emanated from 
 spontaneous generation. If your belief, was that life 
 formed by biogenesis, then you would have to answer the 
 question, “which came first, the chicken or the egg.” My 
 reasoning for my opinion is quite simple, since 
 coacervates are made from a mixture of proteins and 
 carbohydrates and, according to my biology book, 
 “coacervatelike structures evolved, by a process 
 involving many steps, into the first prokaryotic cell,” 
 it is possible that some living organism could be 
 formed by this process. Other scientists opposing the 
 abiogenesis theory, like Redi, did experiments to prove 
 their theory. However, the use of flies in Redi’s 
 experiment, could have been his problem. Maybe, larva 
 is too big to be produced by abiogenesis. Spallazani (an 
 Italian naturalist) duplicated Needham’s experiment, which 
 proved the abiogenesis theory, by corking flasks which 
 Needham only loosely corked. Spallazani’s results were 
 that there was no life in the corked flasks, however no 
 air could get into sealed the flasks, therefore, his 
 experiment was useless. 
 
 I also believe that the Heterotroph hypothesis is a 
 possible explanation of the way life originated. I 
 think this mainly because of the similarity between the 
 chemical evolution and the spontaneous generation 
 theories. The chemical evolution theory is in a way a 
 type of abiogenesis, because it deals with organic 
 molecules forming from energy sources and the atmosphere 
 composed of gases, methane, hydrogen, ammonia, and water 
 vapor, all of which are non-living things. 
 
 Life is the most important entity, it was started by 
 abiogenesis, and led to almost every known thing. 
 
 
 REFERENCES
 Baird, Thomas M. and others, Biology: The Living World. 
 Englewood Cliffs, NJ: Prentice Hall, 1989.
 Chaisson, Eric, Cosmic Dawn: The Origins of Matter and Life. 
 Boston: Little, Brown & Company -in association with- 
 The Atlantic Monthly Press, 1981.
 Dillon, Lawerence S., The Science of Life. 
 New York: The Macmillan Company, 1964. 
 Dodson, Bert and Mahlon Hoagland, The Way Life Works. 
 New York: Times Books, 1995.
 “Universe,” The Dorling Kindersley Visual Encyclopedia. 
 New York: Dorling Kindersley Publishing, Inc., 1995.