Powered By Blogger

mercoledì 30 maggio 2012

CONSERVAZIONE DELL'ENERGIA MECCANICA

Conservazione dell'energia meccanica. Tabella creata con Excel.

lunedì 14 maggio 2012

Ecologia

Popolazione:
si definisce popolazione un’insieme di individui della stessa specie che vive in un determinato habitat.

lunedì 7 maggio 2012

IL PASSATO DELLA BIOSFERA

The terrestrial environment, where it appeared that life was different from environment where we live today. The first living cell was born 3.5 billion years ago. The first living beings were ''organisimi unicellulari procarioti''. They were very simple. From about 1.2 billion years ago, there was the appearance of organisimi ''unicellulari eucarioti'' equipped with a cell more complex.

700 million years ago: Fossili di ediacara
500 million years ago: Trilobiti
400 million years ago: Ostracodermi and Placodermi (the first fish), Pikaia


the evolution of the human species
 
3 million years ago: Australopithecus afarensis
2,5 million years ago: Homo abilis
1,5 million years ago: Homo erectus
300 thousand years ago: Homo sapiens