sâmbătă, 25 aprilie 2009

Despre viata


Ce inseamna viata asta de fapt?hai sa vedem definitia data de Wikipedia:

Life is a characteristic of organisms that exhibit certain biological processes such as chemical reactions or other events that results in a transformation. Living organisms are capable of growth and reproduction, some can communicate and many can adapt to their environment through changes originating internally.[1] A physical characteristic of life is that it feeds on negative entropy.[2][3] In more detail, according to physicists such as John Bernal, Erwin Schrödinger, Eugene Wigner, and John Avery, life is a member of the class of phenomena which are open or continuous systems able to decrease their internal entropy at the expense of substances or free energy taken in from the environment and subsequently rejected in a degraded form (see: entropy and life).[4][5]

An entity with the above properties is considered to be a living organism, hence, a 'life form'. However, not every definition of life considers all of these properties to be essential. For example, the capacity for evolution is sometimes[citation needed] taken as the only essential property of life; this definition notably includes viruses, which do not qualify under narrower definitions as they are acellular and do not metabolize.

A diverse array of living organisms can be found in the biosphere on Earth. Properties common to these organisms—plants, animals, fungi, protists, archaea and bacteria—are a carbon- and water-based cellular form with complex organization and heritable genetic information. They undergo metabolism, possess a capacity to grow, respond to stimuli, reproduce and, through natural selection, adapt to their environment in successive generations. So far, there is no evidence of extraterrestrial life.

...care va sa zica viata e o caracteristica a organismelor in care au loc procese biologice, se produc reactii chimice si alte procese care conduc la transformari ale acestora...sunt capabile de crestere si reproducere, unele pot comunica si multe se pot adapta la mediu. Potrivit unor fizicieni viata e un sistem deschis sau continuu capabil sa-si scada entropia pe baza unor substante si a energiei luate din mediul inconjurator (entropia in termodinamica fiind o masura a cat de aproape de echilibrul termodinamica este un sistem termodinamic...) ok dpdv fizic am conturat cat de cat o definitie, dar cred ca putini sunt interesati de definitia fizica...

Cea mai importanta mi se pare capacitatea de adaptabilitate care e fundamentala pentru a asigura supravieturirea adica perpetuarea vietii si dovada stau multitudinea de specii animale,vegetale care in timp au disparut au fost insa altele care au supravietuit milioane de ani.Ce le-a asigurat supravieturirea??tocmai capacitatea extraordinara de a se adapta permanent noilor conditii de mediu.Cele mai vechi forme de viata se pare ca sunt buretii marini, substantele descoperite in niste roci din Oman avand o vechime de peste 635 milioane de ani continand un tip de colesterol produs doar de buretii marini.

What about humans?!

Omul e o forma de viata superioara (crede el...) prin ce??prin capacitatea de a vorbi, gandi(unii...), prin mersul biped si degetul opozant care il deosebeste de maimute?maybe...hmm dar oare intre buretii marini si specia umana cine a castigat pana acum batalia pentru supravietuire?!

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