Computer Sciences

Study explores privacy of prison communications

People serving time in prison or jail in the United States, which has the highest incarceration rate in the world, are almost constantly being monitored. The surveillance even stretches into communications between inmates ...

Energy & Green Tech

Chill out: Advanced solar tech runs cooler and lasts longer

Australian photovoltaics researchers have made a 'cool' discovery: Singlet fission and tandem solar cells—two innovative ways to generate solar power more efficiently—also help to lower operating temperatures and keep ...

Energy & Green Tech

Perovskite solar modules: High efficiency on a large surface area

From cell to module without loss of efficiency: This is one of the main challenges of perovskite photovoltaics. Researchers at Karlsruhe Institute of Technology (KIT) have now managed to produce perovskite solar modules with ...

Energy & Green Tech

Closing in on state-of-the-art semiconductor solar cells

A synthetic approach that improves absorber layers in perovskite solar cells could help them achieve their full potential and draw closer to the performance of leading gallium arsenide devices.

Energy & Green Tech

Electric vehicle batteries: The older they get, the safer they are

Studies at TU Graz show that the older an traction battery of electric vehicles (EV) is, the lower the danger it poses. Now the researchers and industry partners want to define parameters for the subsequent use of discarded ...

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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