Energy & Green Tech

Power-generating material for organic photovoltaics

Toyobo Co., Ltd. and the French government research institute CEA have succeeded in making trial organic photovoltaic (OPV) small cells on a glass substrate with the world's best conversion efficiency in a dim room. The team ...

Energy & Green Tech

Electrical transients quantify charge loss in solar cells

Solar cells are photovoltaic devices that convert light to electricity. During the photoelectric conversion process, a photovoltaic device internally undergoes multiple charge-carrier dynamics processes. These internal charge-carrier ...

Energy & Green Tech

Image: Bendy, ultra-thin solar cell

ESA has backed the creation of this flexible, ultra-thin solar cell to deliver the best power to mass ratio for space missions.

Energy & Green Tech

New record could usher in new era for solar energy

The future of solar technology is almost reality, with researchers at The Australian National University (ANU) setting a new record for the conversion of sunlight into energy.

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Cell (biology)

The cell is the structural and functional unit of all known living organisms. It is the smallest unit of an organism that is classified as living, and is often called the building block of life. Some organisms, such as most bacteria, are unicellular (consist of a single cell). Other organisms, such as humans, are multicellular. (Humans have an estimated 100 trillion or 1014 cells; a typical cell size is 10 µm; a typical cell mass is 1 nanogram.) The largest known cell is an unfertilized ostrich egg cell.

In 1835 before the final cell theory was developed, a Czech Jan Evangelista Purkyně observed small "granules" while looking at the plant tissue through a microscope. The cell theory, first developed in 1839 by Matthias Jakob Schleiden and Theodor Schwann, states that all organisms are composed of one or more cells. All cells come from preexisting cells. Vital functions of an organism occur within cells, and all cells contain the hereditary information necessary for regulating cell functions and for transmitting information to the next generation of cells.

The word cell comes from the Latin cellula, meaning, a small room. The descriptive name for the smallest living biological structure was chosen by Robert Hooke in a book he published in 1665 when he compared the cork cells he saw through his microscope to the small rooms monks lived in.

This text uses material from Wikipedia, licensed under CC BY-SA