Energy & Green Tech

Capturing carbon with inspiration from battery chemistry

The need for negative emissions technologies to address our climate crisis has become increasingly clear. At the rate that our planet is emitting carbon dioxide—adding about 50 gigatons every year—we will have to remove ...

Energy & Green Tech

A solution to perovskite solar cell scalability problems

Perovskites are hybrid materials made from metal halides and organic compounds. They have attracted a lot of interest in the field of solar energy because of their light-harvesting capacities combined with a low cost of manufacturing, ...

Electronics & Semiconductors

Uncovering the secret of ternary polymer solar cell success

Solar cells will doubtless play a significant part in a sustainable energy future. Polymer solar cells (PSCs) specifically provide an excellent option because they are cheap to produce and can be both flexible and semitransparent. ...

Electronics & Semiconductors

Scientists decide how to prove out perovskite panels for space power

Perovskites, which have shown enormous potential as a new semiconductor for solar cells, are gaining attention as well as a potential next-generation technology to also power spacefaring missions. As scientists around the ...

Energy & Green Tech

Next-generation solar cells reach 24% efficiency

A German research team has developed a tandem solar cell that reaches 24 percent efficiency—measured according to the fraction of photons converted into electricity (i.e., electrons). This sets a new world record as the ...

Automotive

Japanese e-vehicle battery company to build Kentucky plant

A Japanese electric vehicle battery technology company will build a factory in Kentucky, creating 2,000 jobs in a $2 billion investment that reinforces the state's leadership in battery production, Gov. Andy Beshear said ...

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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