THEORYIES

       We know there are several theories for the explanation of origin of life this is because many of scientists has made several attempts have been made for the explanation of the origin of life.Some of them are:

              1)Theory of special creation.

              2)Theory of spontaneous Generation.

              3)Theory of Catastrophism.

              4)Theory of Panspermia.

                5)Theory  of Chemical Evolution.

            The Five theories of origin of life is listed above.These theories as basics of assumptions.According to the Theory of special creation it was formed for the ancient scriptures in accordance to different religions.And the Theory of spontaneous generation it is assumed that living organisms are formed by sudden and spontaneous arise from a non-living matter.The Theory of catastrophism is a modification that has been made to the theory of special creation.Theory of Panspermia is  life has reached this planet Earth from other heavenly bodies such as meteorites, in the form of highly resistance spores of some organisms.And the THEORY OF CHEMICAL EVOLUTION states that  Origin of life on earth is the result of a slow and gradual process of chemical evolution. In these above theories the theory of chemical evolution is mostly accepted than the other theories.

                     The first theory that is theory of special creation in this theory the different forms of life that we found today in the earth,has been be created by the god.This theory is according to the ancient scriptures of all the religions.Let us consider,According to the Hindu mythology,it is believed that,lord Brahma,is the God of creation,how creates humans according to his wish.And in the christian belief,The god created this universe,plant,animals and the human beings.And the Sikh mythology is believed that all forms of life also human beings came from a single word of god.This theory is only according to the belief of religious concept and it has not got any scientific basics.

                      And,the second theory of spontaneous Generation it is believed that the living organisms are  could arises suddenly and spontaneously from any kind of non-living matter.Aristotle the Greek philosopher was the firm believer of the spontaneous Generation.According to his belief the dead leaves falling from a tree into a pond that would transport into fishes, and that has been felled into soils turned into worms,and to the insects.And it is also the Egyptians believed that the mud of the Nile river which could spontaneously give rise to many forms of life.And the theory of spontaneously lost its significant in the course of time due to the experiment that has been conducted by Francisco Redi,Spallanzani and later by Louis Pasteur in his famous Swan neck experiment.The theory was disapproved because the scientist gave a definite proof that life comes from pre-existing life.

          The third theory is simply the modification to the theory of special creation.According to this law there have been several creation of God,in which each is preceded by a catastrophe which resulting from some kind of geological disturbance.

According to this theory, since each catastrophe completely destroyed the existing life, each new creation consisted of life form different from that of previous ones.The scientists like George Cuvier and Orbigney where was the main supporter of this law.
                      And the fourth theorem that is the theory of Panspermia which is also know as the  Cosmozoic theory.According to this theory the scientist Richter found that Life has reached this earth planet from an other heavenly bodies such as meteorites,which is in the form of highly resistance spores of some organisms.This theory was also supported by Arrhenius and other scientists.And this theory does not gain any support because this theory has lack of evidence and this theory was Discarded.

                          The firth theory that is theory of  chemical Evolution which is also know as Physico-chemical theory or Materialistic Theory. In this theory the scientists A.l Oparin a Russian scientist and an English scientist J.B.S Haldane proposed that the Origin of the life on earth is due to the reason of slowly and gradual process of chemical evolution which may be occurred about 3.8 billion years ago.Considering to other theories it is most accepted theory by the scientists and the scientists are still continuing there research for new theories. 

DEFINITIONS

 

                                  It is a challenge for scientists and philosophers to define life in unequivocal terms.This is difficult partly because life is a process, not a pure substance.Any definition must be sufficiently broad to encompass all life with which we are familiar, and must be sufficiently general to include life that may be fundamentally different from life on Earth.Some may even consider that life is not real at all, but a concept instead.

BIOLOGY
                             We all know that the life Since has no unequivocal definition of life,and so the current understanding is only descriptive.The life is considered as the characteristic of something that exhibits all or most of the following traits.  
Homeostasis:The Homeostasis is the Regulation of the internal environment to maintain a constant state.Let us consider the example,that the electrolyte concentration or the sweating to reduce the temperature..
Organization:Organization is structurally composed which has one or more cells has the basic unit of life.
Metabolism: Transformation of energy by converting chemicals and energy into cellular components (anabolism) and decomposing organic matter (catabolism). Living things require energy to maintain internal organization (homeostasis) and to produce the other phenomena associated with life.
Growth: Maintenance of a higher rate of anabolism than catabolism. A growing organism increases in size in all of its parts, rather than simply accumulating matter.
Adaptation: The ability to change over time in response to the environment. This ability is fundamental to the process of evolution and is determined by the organism's heredity, diet, and external factors.
Response to stimuli: A response can take many forms, from the contraction of a unicellular organism to external chemicals, to complex reactions involving all the senses of multicellular organisms. A response is often expressed by motion; for example, the leaves of a plant turning toward the sun (phototropism), and chemotaxis.
Reproduction: The ability to produce new individual organisms, either asexually from a single parent organism, or sexually from two parent organisms.

These complex processes, called physiological functions, have underlying physical and chemical bases, as well as signaling and control mechanisms that are essential to maintaining life.

ORIGIN OF LIFE

   

             Origin of life is a scientific problem which is not yet solved.Actually there are plenty of ideas,but a few are only clear facts.It is generally agreed that life today is formed by common descent from a single primitive lifeforms.No one this world those not know how the life is early formed ,but all the scientists concluded that they are formed by natural process which may be think ed to took palace about 3,900 million years ago.Scientists concluded to this because in accordance with a philosophy which is called as naturalism, that is which is occurred due to natural causes.While we are saying about out origin of life we also must say about spontaneous generation,then what is spontaneous generation is meant about until the 19th early century many scientist and many other peoples believed in the regular spontaneous generation of life from non-living matter.That is called as spontaneous generation,but the Louis Pasteur was disproved it later.Louis Pasteur showed that later that without spores that no bacteria or virus where grew on sterile materials.We also must say that while discussing origin of life we must also say that Joseph Dalton Hooker got a letter on 11th Feb 1871 in that he got that Charles Darwin proposed a natural process for origin of life.

             Charles Darwin suggested that in 1873 that the original spark of life may have begun in a "Warm Little Pond"that must also consist of  with all sort of ammonia,phosphoric salt,light,and heat etc.According to him a Protein compound was then chemically formed ready to undergo still more complex changes.He also doesn't forget to explain present days .He explained about present days such matters would be instantly devoured or absorbed,which was not has been the case before living creatures were formed or originated.

             We must also consider HALDANE and OPARIN according to this no real  progress was made until 1924 when Alexander oparin said that atmospheric oxygen prevent the synthesis of the organic molecules.Synthesis means combination of two or more entities that which together form something new,it also means or refer to the creating of something by artificial means. In evolution of life the organic molecules are too necessary building block or which also is an important factor.According to the Alexander the origin of life he argued that a "primeval soup"which has an no of organic molecules could be created in an oxygen-less atmosphere by the action of sunlight.and he said that these  would combine in ever-more complex fashion until they are formed  as droplets.And these droplets would grows up by the fusion that undergoes with the other droplets,which in turn and reproduce through the action of  fission into daughter droplets,and which have a primitive metabolism in which the factors that promote "cell integrity"survive,and those do not become extinct. In modern theories also the Alexander oparin's idea is taken has a starting point.

             And when around the same time J.B.S.Haldane where also suggested that the earth's  pre-bio tic ocean's,which is to be very different that we see from todays ocean,In ocean would have formed a "HOT DILUTE SOUP".In which this soup,that is organic compounds,the building block of life,assumed to be could have been formed.This idea was called as the biopoiesis,the process of living matter evolving from self-replicating but nonliving molecules.This is to be considered as the evolution of life.
             The origin of life from the evidences found that life on the earth existed for at least 3.5 billion years ago.In a National Institutes of Health study, the authors hypothesis that if biological complexity increased exponentially during evolution, life in the universe may have begun nearly 10 billion years ago- billions of years before the Earth existed, suggesting that Earth was seeded by panspermia or directed panspermia. All known life forms share fundamental molecular mechanisms, reflecting their common descent; based on these observations, hypotheses on the origin of life attempt to find a mechanism explaining the formation of a universal common ancestor, from simple organic molecules via pre-cellular life to protocells and metabolism. Models have been divided into "genes-first" and "metabolism-first" categories, but a recent trend is the emergence of hybrid models that combine both categories.This are sentences i have got while reading the origin.Living organisms synthesize proteins, which are polymers of amino acids using instructions encoded by deoxyribonucleic acid (DNA). Protein synthesis entails intermediary ribonucleic acid (RNA) polymers. One possibility for how life began is that genes originated first, followed by proteins; the alternative being that proteins came first and then genes.We know that genes and protein are both required to produce the other,for example consider whether the chicken or egg is firt produced.We know that chickens are produced from the egg that are formed by chickens.Most scientists have adopted the hypothesis that because of this, it is unlikely that genes and proteins arose independently.FRANCIS CRICK was the first one to suggest the first life was based on the RNA,which has got the DNA like properties of information storage and the catalytic property of the some of the proteins.which is know asthe RNA world hypothesis,and which is supported by the  observation that the many of the critical components of cell are composed mostly or entirely of RNA. Also, many critical cofactors are either nucleotides or substances clearly related to them. The catalytic properties of RNA had not yet been demonstrated when the hypothesis was first proposed,but they were confirmed by Thomas Cech in 1986.

Evolution

      

                                                        

What is a Evolution?.The change in the  inherited characteristics of biological population over a a lot successive generation  is the Evolution.The diversity at every level of biological organizations, like species,individual organisms and molecules like proteins and DNA is the evolutionary processes.Approximately 3.8 billion years ago All Life On Earth is descended from a last universal ancestor.By the from shared set of biochemical and morphological traits,or else by the DNA sequences that has been shared from the repeated specification and the divergence of the life can be inferred.Those the homologous traits and sequences are more similar among the species that share a more recent same ancestor,and may be used for tore construct evolutionary histories,by the use of both the fossil record and the existing species .Speciation and by the extinction are been shaped by the existing patterns of biodiversity.A scientific argument for the theory of evolution by the means of natural selection was first made by the Charles Darwin. 

                                                                         In the Darwin's theory of evolution by natural selection through the discipline of population genetics early 20th century,genetic was also integrated with Darwin's theory.It was accepted into other branches of biology because of the importance of natural selections because of the as a cause of evolution.Scientists continue to study various aspects of evolution by forming and testing hypotheses, constructing scientific theories, using observational data, and performing experiments in both the field and the laboratory.The most reliably established facts in science is the descent with modification it was also agreed by the biologists.The discoveries in evolutionary biology have made a significant impact not only one the traditional branches of biology,and also in the other academic disciplines and on society at large.

life

                                                                         LIFE 

What is life?.Have any one of us thought about it. Can any one us knows about it.Is life is what we see today. Life is a characteristic distinguishing objects having signalling and self-sustaining processes from those that do not,either because such functions have ceased (death), or because they lack such functions and are classified as inanimate.This are we word that i have got while checking in Internet.Life is a study concerned with science of biology.An organism is any contiguous living system.Organisms undergo metabolism, maintain homeostasis, can grow, respond to stimuli, reproduce and, through natural selection, adapt to their environment in successive generations. More complex organisms can communicate through alternative means.A diverse array of living organisms can be found in the biosphere of Earth, and the properties common to these organisms—plants, animals, fungi, protests, Archer, and bacteria—are a carbon- and water-based cellular form with complex organisation and heritable genetic information.

The Earth was formed about 4.54 billion years ago. The earliest life on Earth existed at least 3.5 billion years ago,during the Archean Era when sufficient crust had solidified following the molten Ha dean Eon. The earliest physical evidence for life on Earth is bionic graphite in 3.7 billion-year-old meta sedimentary rocks discovered in Western Greenland and microbial mat fossils found in 3.48 billion-year-old sandstone discovered in Western Australia.Nevertheless, several studies suggest that life on Earth may have started even earlier, as early as 4.25 billion years ago according to one study, and even earlier yet, 4.4 billion years ago, according to another study. The mechanism by which life began on Earth is unknown, although many hypotheses have been formulated. Since emerging, life has evolved into a variety of forms, which biologists have classified into a hierarchy of tax's. Life can survive and thrive in a wide range of conditions.Actually this are the words that i have got while researching the information.Ever humans want there life and there families life to be safe they ever doesn't considers other life or even does not think about them.Also life is also a mixture of happy,sadness,sorrow etc.Every humans must also posses this situations in there life.No humans in this world are always happy every person has some sorrow or sadness in life.so life is a mixture of happiness,sadness,sorrow etc.