Related topics: proceedings of the national academy of sciences , cancer , cancer cells , stem cells , immune system



Cell (biology)

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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.

For more information about Cell (biology), read the full article at Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.


News tagged with cells

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Implant-based cancer vaccine is first to eliminate tumors in mice

Implant-based cancer vaccine is first to eliminate tumors in mice

Medicine & Health / Cancer

created Nov 25, 2009 | popularity 4.7 / 5 (31) | comments 7

(PhysOrg.com) -- A cancer vaccine carried into the body on a carefully engineered, fingernail-sized implant is the first to successfully eliminate tumors in mammals, scientists report this week in the journal ...


A mathematical model of a simple circuit in a chicken brain raises fundamental questions about our understanding of neural circu

Mathematical model of a simple circuit in a chicken brain raises fundamental questions

Physics / General Physics

created Dec 01, 2009 | popularity 4.6 / 5 (28) | comments 17

(PhysOrg.com) -- The Web site Neuroanthropology asks visitors to complete this quote, "One of the difficulties in understanding the brain is ...". In addition to the typical facetious remarks, such as "so ...


Innovation puts next-generation solar cells on the horizon

Chemistry / Materials Science

created Dec 01, 2009 | popularity 4.3 / 5 (30) | comments 12

In a world first, a Monash University-led international research team has developed an innovative way to boost the output of the next generation of solar cells.


Researchers show brain waves can 'write' on a computer in early tests

Medicine & Health / Research

created Dec 07, 2009 | popularity 4.9 / 5 (18) | comments 3

Neuroscientists at the Mayo Clinic campus in Jacksonville, Fla., have demonstrated how brain waves can be used to type alphanumerical characters on a computer screen. By merely focusing on the "q" in a matrix of letters, ...


Bigger not necessarily better, when it comes to brains

Bigger not necessarily better, when it comes to brains

Biology / Plants & Animals

created Nov 17, 2009 | popularity 4.5 / 5 (19) | comments 12

(PhysOrg.com) -- Tiny insects could be as intelligent as much bigger animals, despite only having a brain the size of a pinhead, say scientists at Queen Mary, University of London.


Researchers demonstrate that stem cells can be engineered to kill HIV

Medicine & Health / HIV & AIDS

created Dec 08, 2009 | popularity 4.9 / 5 (17) | comments 0

(PhysOrg.com) -- UCLA AIDS Institute researchers have for the first time demonstrated that human blood stem cells can be engineered to target and kill HIV-infected cells.


Tiny magnetic discs could kill cancer cells: study

Nanotechnology / Bio & Medicine

created Nov 29, 2009 | popularity 3.8 / 5 (22) | comments 4

Tiny magnetic discs just a millionth of a metre in diameter could be used to used to kill cancer cells, according to a study published on Sunday.


Measuring Electron Orbitals

Measuring Electron Orbitals

Physics / General Physics

created Nov 16, 2009 | popularity 5 / 5 (8) | comments 0

(PhysOrg.com) -- For the first time, it has been possible to measure electron density in individual molecular states using what is known as the photoelectric effect. Now published in Science, this method repres ...


Two molecules affecting brain plasticity

Medicine & Health / Neuroscience

created Nov 25, 2009 | popularity 4.9 / 5 (8) | comments 1

(PhysOrg.com) -- You wouldn't want a car with no brakes. It turns out that the developing brain needs them, too.


The Future in Two Words: Ionic Liquids

The Future in Two Words: Ionic Liquids

Chemistry / Materials Science

created Nov 13, 2009 | popularity 4.4 / 5 (8) | comments 0

(PhysOrg.com) -- Ionic liquids are molecular solutions that have a wide range of potential applications, including next-generation solar cells, hydrogen fuel cells and lithium batteries.


Beyond genomics, biologists and engineers decode the next frontier

Beyond genomics, biologists and engineers decode the next frontier

Biology / Cell & Microbiology

created Nov 18, 2009 | popularity 5 / 5 (7) | comments 0

(PhysOrg.com) -- A team of Princeton biologists and engineers has dramatically improved the speed and accuracy of measuring an enigmatic set of proteins that influences almost every aspect of how cells and ...


Scientists use virus to kill cancer cells while leaving normal cells intact

Medicine & Health / Cancer

created Dec 03, 2009 | popularity 5 / 5 (7) | comments 3

(PhysOrg.com) -- A virus that in nature infects only rabbits could become a cancer-fighting tool for humans. Myxoma virus kills cancerous blood-precursor cells in human bone marrow while sparing normal blood stem cells, a ...


Study shows new brain connections form rapidly during motor learning

Study shows new brain connections form rapidly during motor learning

Medicine & Health / Neuroscience

created Nov 29, 2009 | popularity 4.9 / 5 (7) | comments 0

(PhysOrg.com) -- New connections begin to form between brain cells almost immediately as animals learn a new task, according to a study published this week in Nature. Led by researchers at the University of Cal ...


Researchers find explanation for rapid maturation of neurons at birth

Medicine & Health / Neuroscience

created Nov 17, 2009 | popularity 4.3 / 5 (7) | comments 2

At the moment a newborn switches from amniotic fluid to breathing air, another profound shift occurs: nerve cells in the brain convert from hyperexcitability to a calm frame against which outside signals can be detected.


Tumor-attacking virus strikes with 'one-two punch'

Medicine & Health / Cancer

created Dec 01, 2009 | popularity 5 / 5 (6) | comments 0

Ohio State University cancer researchers have developed a tumor-attacking virus that both kills brain-tumor cells and blocks the growth of new tumor blood vessels.