Energy & Green Tech

Dye-sensitized solar cells that adapt to different light conditions

Solar cells made of semi-transparent photovoltaic (PV) materials typically have a fixed optical transmission, which results in either high transparency or high efficiency, but rarely both. In order to perform optimally when ...

Energy & Green Tech

Researchers advance fuel cell technology

Washington State University researchers have made a key advance in solid oxide fuel cells (SOFCs) that could make the highly energy-efficient and low-polluting technology a more viable alternative to gasoline combustion engines ...

Energy & Green Tech

A cool approach to defect-free solar cells

Chemists regularly use high temperatures to make things happen, but sometimes keeping cool can work better. Researchers at KAUST are discovering that a low-temperature approach can make better single crystals for use in solar ...

Energy & Green Tech

New system for widespread availability of green hydrogen

Hydrogen researchers at Graz University of Technology, together with the Graz-based start-up Rouge H2 Engineering, have developed a cost-effective process for the decentralised production of high-purity hydrogen.

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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