Medical research

First lung map uncovers new insights into asthma

For the first time, researchers have mapped the building blocks of the human lungs and airways, in both asthma patients and normal people. The research from the Wellcome Sanger Institute, University Medical Center Groningen, ...

Neuroscience

Is multiple sclerosis linked to childhood viral infections?

Although the exact causes of multiple sclerosis still remain unknown, it is assumed that the disease is triggered by a combination of genetic and environmental risk factors. But which? In a mouse model of the disease, researchers ...

Oncology & Cancer

Confining cell-killing treatments to tumors

Cytokines, small proteins released by immune cells to communicate with each other, have for some time been investigated as a potential cancer treatment.

Oncology & Cancer

Childhood leukemia cannot hide from the immune system

St. Jude Children's Research Hospital scientists have evidence that children with acute lymphoblastic leukemia mount a robust immune response to their cancer. The findings, which appear today in the journal Science Translational ...

Oncology & Cancer

Scientists discover molecular key to how cancer spreads

Yale researchers have discovered how metastasis, the spread of cancer cells throughout the body, is triggered on the molecular level, and have developed a tool with the potential to detect those triggers in patients with ...

Immunology

Discovery may help kick-start ageing immune system

The thymus is the powerhouse producing the immune system's T cells, which combat infection in our body. Yet this vital organ is one of the first to diminish in function as we age, resulting in a gradual loss of T cell production ...

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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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