Energy & Green Tech

Photovoltatronics: Smart solar cells that talk to each other

Imagine you're walking through the city on a sunny summer day. You look at the skyscrapers, the shop buildings, lampposts and electric taxis driving tirelessly to and fro. What you can't see is that every single piece of ...

Electronics & Semiconductors

New semiconductor coating may pave way for future green fuels

Hydrogen gas and methanol for fuel cells, or as raw materials for the chemicals industry, for example, could be produced more sustainably using sunlight, a new Uppsala University study shows. In this study, researchers have ...

Engineering

Jet-printing complex circuits using microfluidics

Biomedical applications in life sciences can greatly benefit from microfluidics devices; however, the technology is suboptimal for rapid production and applications in biolabs. For instance, solid opaque walls of conventional ...

Energy & Green Tech

US nuclear lab partnering with utility to produce hydrogen

The U.S. Department of Energy has awarded just under $14 million for an attempt to build a hydrogen-energy production facility at a nuclear power plant in Minnesota with the help of a nuclear research lab in Idaho.

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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