Diabetes

New hope for stem cell approach to treating diabetes

Scientists working to develop more effective treatments for diabetes are turning to stem cells. Such cells can be transformed into cells that produce insulin, the hormone that controls blood sugar.

Neuroscience

Study finds the circuits that may help you keep your cool

The big day has come: You are taking your road test to get your driver's license. As you start your mom's car with a stern-faced evaluator in the passenger seat, you know you'll need to be alert but not so excited that you ...

Cancer

Targeted treatment shrinks deadly pediatric brain tumors

Chemotherapy and radiation are effective cancer treatments because they kill rapidly dividing cells, including tumor cells. But for children—whose tiny bodies are still growing—these treatments can cause lifelong damage. ...

Cancer

From microfluidics to metastasis

Circulating tumor cells (CTCs)—an intermediate form of cancer cell between a primary and metastatic tumor cell—carry a treasure trove of information that is critical to treating cancer. Numerous engineering advancements ...

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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.

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