Robotics

Microrobots to change the way we work with cellular material

In a new study published in the Proceedings of the National Academy of Sciences, researchers from University of Toronto have demonstrated a novel and non-invasive way to manipulate cells through microrobotics.

Energy & Green Tech

Experiments show dramatic increase in solar cell output

In any conventional silicon-based solar cell, there is an absolute limit on overall efficiency, based partly on the fact that each photon of light can only knock loose a single electron, even if that photon carried twice ...

Robotics

Robot arm tastes with engineered bacteria

A robotic gripping arm that uses engineered bacteria to "taste" for a specific chemical has been developed by engineers at the University of California, Davis, and Carnegie Mellon University. The gripper is a proof-of-concept ...

Telecom

National emergency alerts potentially vulnerable to attack

On October 3, 2018, cell phones across the United States received a text message labeled "Presidential Alert." The message read: "THIS IS A TEST of the National Wireless Emergency Alert System. No action is needed."

Computer Sciences

Spintronic memory cells for neural networks

In recent years, researchers have proposed a wide variety of hardware implementations for feed-forward artificial neural networks. These implementations include three key components: a dot-product engine that can compute ...

Energy & Green Tech

How to speed up the discovery of new solar cell materials

A broad class of materials called perovskites is considered one of the most promising avenues for developing new, more efficient solar cells. But the virtually limitless number of possible combinations of these materials' ...

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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