Related topics: protein · cancer cells · cancer · stem cells · immune system

Scientists identify first negative regulator of NOX4 translation

Nicotinamide adenine dinucleotide phosphate oxidase 4 (NADPH oxidase 4, NOX4) is an important member of the NADPH oxidase family that is primarily responsible for the production of H2O2. The regulation of NOX4 activity is ...

Implantable batteries can run on the body's own oxygen

From pacemakers to neurostimulators, implantable medical devices rely on batteries to keep the heart on beat and to dampen pain. But batteries eventually run low and require invasive surgeries to replace.

page 1 from 40

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