Biology

Bacteria or prokaryotes are the most common living beings on Earth: one spoonful of soil can contain, for instance, up to 10,000 billion bacteria. They are unicellular organisms, i.e. they consist of one cell only. They are very small in size, since a large part of bacterial cells have a diameter of 1 to 10 microns (one micron equals one thousandth of a millimetre), so an orderly row of one thousand bacteria would be just one millimetre long. Bacterial cells, unlike the cells of superior organisms (eukaryotes), do not have organelles enwrapped in membranes (nucleus, Golgi apparatus…) or chromosomes. Chromosomes are structures made of DNA wrapped around proteins, called histones, and their purpose is to make the long DNA molecules contained in the nucleus more compact and orderly.
Chromosomes are essential since they arrange the large amount of genetic material contained in eukaryote cells: if, for instance, the DNA contained in just one human somatic cell were unwrapped, the resulting molecule would be approximately two metres long! In bacteria, instead, the DNA is not contained in a nucleus and is round in shape. Another specific feature of bacteria is their protective structure (the wall) that enwraps and encloses the whole cell. The cellular wall is composed of proteins and sugars and, as well as protecting the micro-organism, it puts the cell in contact with the external environment and the other bacterial cells.

Special reports

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    Bioindicators

    Ecologic research is more and more oriented towards an...

    15 March 2008

    Biodiversity

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    4 March 2010

    Biotechnological cleaners

    In today’s society, more than 80% of human activities are...

  • 10 March 2006

    Environment biotech

    Biotechnology can be defined as the application of microbiology...

    1 October 2005

    Virus

    “Virus” is an ancient Latin word that means poison. It sounds scary for...

    20 September 2005

    Sanitary emergency

    The modality study and the death entity...

  • 1 December 2005

    H5N1

    The term pandemic indicates a disease that affects...

    15 February 2008

    Looking for DNA

    Everyone knows the novel or has seen the film Jurassic Park...

    4 April 2013

    Carbon (14C) dating method

    The radiocarbon dating method...

  • 10 May 2008

    Bioindicators

    Ecologic research is more and more oriented towards an...

    15 March 2008

    Biodiversity

    Much is said about biodiversity and of the need to protect it...

  • 4 March 2010

    Biotechnological cleaners

    In today’s society, more than 80% of human activities are...

    10 March 2006

    Environment biotech

    Biotechnology can be defined as the application of microbiology...

  • 1 October 2005

    Virus

    “Virus” is an ancient Latin word that means poison. It sounds scary for...

    20 September 2005

    Sanitary emergency

    The modality study and the death entity...

  • 10 May 2008

    Bioindicators

    Ecologic research is more and more oriented towards an...

  • 15 March 2008

    Biodiversity

    Much is said about biodiversity and of the need to protect it...

  • 4 March 2010

    Biotechnological cleaners

    In today’s society, more than 80% of human activities are...

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Facts

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    Many sea animals, including a lot of fish and molluscs that live in the dark in the ocean depths...

    Bacteria as detergents

    Enzymes are proteins produced by the cells of all living organisms...

    Bacteria as miners

    The ability of chemoautotrophic bacteria to take energy from...

  • Bacteria as Sherlock Holmes

    A drop of blood, a fragment of skin or a hair found on the scene of a crime can supply…

    Down-pouring bacteria

    It sounds incredible, but recent researches have found that bacteria can cause some atmospheric phenomena...

    High-fashion bacteria

    Some bacteria, the Clostridia, were used to make textile fibres...

  • Let’s eat!

    The economic importance of fungi is increased by the “edible” mushrooms...

    Predator mushroom

    <em>Pleutrotus ostreatus</em> mushroom does not have teeth or claws but it is...

    Decomposing organisms

    The ability to destroy organic matter has been used by man...

  • 13 May 2011

    Bio-luminescence

    Many sea animals, including a lot of fish and molluscs that live in the dark in the ocean depths...

    Bacteria as detergents

    Enzymes are proteins produced by the cells of all living organisms...

  • Bacteria as miners

    The ability of chemoautotrophic bacteria to take energy from...

    Bacteria as Sherlock Holmes

    A drop of blood, a fragment of skin or a hair found on the scene of a crime can supply…

  • Down-pouring bacteria

    It sounds incredible, but recent researches have found that bacteria can cause some atmospheric phenomena...

    High-fashion bacteria

    Some bacteria, the Clostridia, were used to make textile fibres...

  • Bio-luminescence

    Many sea animals, including a lot of fish and molluscs that live in the dark in the ocean depths...

  • Bacteria as detergents

    Enzymes are proteins produced by the cells of all living organisms...

  • Bacteria as miners

    The ability of chemoautotrophic bacteria to take energy from...