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



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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Skull bone may hold the key to tackling osteoporosis

Medicine & Health / Research

created 10 hours ago | popularity 5 / 5 (2) | comments 0

Scientists at Queen Mary, University of London have uncovered fundamental differences between the bone which makes up the skull and the bones in our limbs, which they believe could hold the key to tackling bone weakness and ...


UAB researchers link calorie intake to cell lifespan, cancer development

Researchers link calorie intake to cell lifespan, cancer development (w/ Video)

Medicine & Health / Research

created Dec 17, 2009 | popularity 4.4 / 5 (11) | comments 7

Researchers from the University of Alabama at Birmingham (UAB) have discovered that restricting consumption of glucose, the most common dietary sugar, can extend the life of healthy human-lung cells and speed ...


Scientists isolate new antifreeze molecule in Alaska beetle

Chemistry / Biochemistry

created Dec 14, 2009 | popularity 5 / 5 (14) | comments 4

Scientists have identified a novel antifreeze molecule in a freeze-tolerant Alaska beetle able to survive temperatures below minus 100 degrees Fahrenheit. Unlike all previously described biological antifreezes that contain ...


Hot electron solar cell

Hot Electrons Could Double Solar Cell Power Efficiency

Nanotechnology / Nanophysics

created Dec 18, 2009 | popularity 4.3 / 5 (10) | comments 2

Scientists have experimentally verified a theory suggesting that hot electrons could double the output of solar cells. The researchers, from Boston College, have built solar cells that successfully use hot ...


Biological catch-22 prevents induction of antibodies that block HIV

Medicine & Health / HIV & AIDS

created Dec 15, 2009 | popularity 4.5 / 5 (2) | comments 2

Scientists seeking to understand how to make an AIDS vaccine have found the cause of a major roadblock. It turns out that the immune system can indeed produce cells with the potential to manufacture powerful HIV-blocking ...


Researchers create new 'smart' nanocapsule delivery system for use in protein therapy

Nanotechnology / Bio & Medicine

created Dec 18, 2009 | popularity 5 / 5 (2) | comments 1

the delivery of healthy proteins directly into human cells to replace malfunctioning proteins — is considered one of the most direct and safe approaches for treating diseases. But its effectiveness has been limited by low ...


How to Find Signs of Life on Mars

How to Find Signs of Life on Mars

Space & Earth / Space Exploration

created Dec 18, 2009 | popularity 3.7 / 5 (3) | comments 1

By studying the signatures of fossil life on Earth, geobiologists can get a clue of what to look for when hunting for extraterrestrial life on Mars.


Study reveals chemo's toxicity to brain, possible treatment

Medicine & Health / Cancer

created Dec 17, 2009 | popularity 5 / 5 (2) | comments 0

Researchers have developed a novel animal model showing that four commonly used chemotherapy drugs disrupt the birth of new brain cells, and that the condition could be partially reversed with the growth factor IGF-1.


Within a cell, actin keeps things moving

Within a cell, actin keeps things moving

Chemistry / Biochemistry

created Dec 17, 2009 | popularity not rated yet | comments 0

(PhysOrg.com) -- Using new technology developed in his University of Oregon lab, chemist Andrew H. Marcus and his doctoral student Eric N. Senning have captured what they describe as well-orchestrated, actin-driven, ...


Pores finding reveals targets for cancer and degenerative disease

Pores finding reveals targets for cancer and degenerative disease

Medicine & Health / Cancer

created Dec 18, 2009 | popularity 5 / 5 (1) | comments 0

Walter and Eliza Hall Institute scientists have identified a key step in the biological process of programmed cell death, also called apoptosis.


Researchers find cells move in mysterious ways

Researchers find cells move in mysterious ways (w/ Video)

Biology / Cell & Microbiology

created Dec 16, 2009 | popularity 4 / 5 (2) | comments 0

Our cells are more like us than we may think. They're sensitive to their environment, poking and prodding deliberately at their surroundings with hand-like feelers and chemical signals as they decide whether ...


Study reveals lack of diversity in embryonic stem cell lines

Biology / Biotechnology

created Dec 16, 2009 | popularity 5 / 5 (1) | comments 0

The most widely used human embryonic stem cell lines lack genetic diversity, a finding that raises social justice questions that must be addressed to ensure that all sectors of society benefit from stem cell advances, according ...


Scientists use DNA sequencing to attack lung cancer

Medicine & Health / Cancer

created Dec 16, 2009 | popularity 5 / 5 (1) | comments 0

Aided by next-generation DNA sequencing technology, an international team of researchers has gained insights into how more than 60 carcinogens associated with cigarette smoke bind to and chemically modify human DNA, ultimately ...


Stem-cell activators switch function, repress mature cells

Medicine & Health / Research

created Dec 16, 2009 | popularity not rated yet | comments 0

In a developing animal, stem cells proliferate and differentiate to form the organs needed for life. A new study shows how a crucial step in this process happens and how a reversal of that step contributes to cancer.


Higher levels of protein hormone associated with lower risk of dementia, Alzheimer's disease

Medicine & Health / Diseases

created Dec 15, 2009 | popularity 5 / 5 (1) | comments 0

Persons with higher levels of leptin, a protein hormone produced by fat cells and involved in the regulation of appetite, may have an associated reduced incidence of Alzheimer disease and dementia, according to a study in ...