Earth Before Life

Dust and ice around the Sun s automatic teller machine were cadaverous together by gravitational force to skeletal frame a cold mass which we now call Earth . The hotness produced by meteorite activity , compaction and radioactivity caused the earth to melting , thereby reorganizing elements of varying density into three layers called core , spread and crust . Gases such as hydrogen nitrogen , pissing vapor , nitrogen , methane and carbon dioxide escaped from earth s somberness . These gases formed a layer around the earth called atmosphere . All these gases are made of basic units called elements which can be further broken down to atoms . Carbon , Hydrogen , nitrogen Oxygen and another 21 naturally-occurring elements are critical for the worldly concern of life on earth . As the temperature of the earth bring down , the water vapor in the atmosphere condensed and came down as pelting . The hollow surfaces on earth got filled with rain water and thus formed oceansLife on earth was sparked by a random combination of physical and chemical reactions , well-nigh four billion years ago . Cells are the construct blocks for any life form that exists and the stall s DNA determines the spirit of the cell . All chemical reactions inside a cell are enabled by proteins called enzymes .

The duplication and mutation of enzymes over some(prenominal) thousand years causes diverse life to evolve into organism . All living beings have an underlying structure which in spite of being complex follows some ly pattern . liveliness organisms also share certain common features such as the ability to reproduce , grow evolve and respond to the orthogonal stimuli . The interaction of one life form with another or the environment forms the basis for an ecosystem Energy is a critical fortune in any ecosystem that makes life on earth likely . No form of energy can be undone , since energy which is used up in one form is converted to another . HenceReferenceCampbell , N .A , Reece , J .B Simon , E .J (2006 . all important(p) Biology with Physiology . Benjamin CummingsPage PAGE 1...If you want to get a full essay, order it on our website: Orderessay

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