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It is easy to imagine that the cells in an organism, which are so different in shape and size, have specialised functions: muscle cells contract, nerve cells transmit nervous impulses, glandular cells secrete, and so on. The shape is directly related to the cell s function.

New observation techniques allow scientists to probe deeper and deeper into the mysteries of life and its structures. We can now plunge into matter, from a 1:1 scale to a molecular scale, using real images obtained by different techniques of electron microscopy. This series of images is then computer-processed to render the impression of smooth, continual motion into the core of living matter.

All life is organised on the level of the cell, which is the smallest autonomous unit.

If the DNA of a human cell were completely unwound it would reach two meters in length! A molecule this size can be contained in a nucleus a few micrometres in diameter because the DNA is coiled up in an extremely compact and organized structure. The hepatitis virus has the smallest known genome (2 micrometres); the amoeba A. dubia contains the largest known genome (400 known genome metres).

The uncoiled DNA from the nucleus of a human cell measures about 2 metres in length. Each DNA molecule is coiled and compacted in several stages through the combined action of different proteins. The more evolved the species, the more its DNA is compressed and packed by structural proteins.

Human DNA acquisition techniques can be applied to different types of cell (skin, white cells, bone Human DNA acquisition techniques can be applied to different types of cell (skin, white cells, bone marrow, foetal cells, etc.). When a blood sample is used, the red cells are Θέμαed to haemolysis. marrow, foetal cells, etc.). When a blood sample is used, the red cells are Θέμαed to haemolysis. They are then centrifuged to obtain a residue of white cells from which the DNA is extracted.

Human DNA acquisition techniques can be applied to different types of cell (skin, white cells, bone Human DNA acquisition techniques can be applied to different types of cell (skin, white cells, bone marrow, foetal cells, etc.). When a blood sample is used, the red cells are Θέμαed to haemolysis. marrow, foetal cells, etc.). When a blood sample is used, the red cells are Θέμαed to haemolysis. They are then centrifuged to obtain a residue of white cells from which the DNA is extracted.

DNA (Deoxyribonucleic Acid) is found in the nuclei of animal and plant cells. It contains all the information that the cell needs to function properly. DNA is made up of two strands coiled in a helix. Each strand consists of a chain of nucleotides which differ in just one of their molecules, called a “base”. There are 4 different bases: adenine (A), thymine (T), guanine (G) and cytosine (C). They hold together the 2 strands of DNA; an A in one strand is always connected to a T in the other strand and C always pairs with G.

The car pollution, such as ozone, carbon dioxide and other pollutants are greenhouse gases

The experiment will show how a complex solution changes color in a circular manner, acting as a chemical clock.

Comets are icy bodies that take their final form when approaching the Sun, as their core evaporates and the solar wind creates the long tail

Large image of the Deep Impact's collision with the comet Tempel 1 and a small picture of comet Wild 2 ( first on the right). The other two images on the right depict the comet NEAT and its long tail

Comets are composed mainly of rock and ice and when they approach the Sun some of the ice in its nucleus turns into gas. Τhe solar wind carries the gas outward forming a long tail

Comets are composed mainly of rock and ice and when they approach the Sun some of the ice in its nucleus turns into gas.Τhe solar wind carries the gas outward forming a long tail

Image of a star like Sun becoming a white dwarf