Diseases, Conditions, Syndromes

Dickkopf-related protein 3 (DKK3) predicts AKI

A new renal biomarker was presented at the ERA-EDTA Congress last year that shows that urinary DKK3 might help to identify patients who are at risk of progressive chronic kidney disease (CKD).

Diseases, Conditions, Syndromes

Sick with the flu? Here's why you feel so bad

"You never forget the flu." This is the title of the Victorian health department's current campaign, which highlights people's recollections of having the flu.

Neuroscience

Scientists develop 'mini-brain' model of human prion disease

National Institutes of Health scientists have used human skin cells to create what they believe is the first cerebral organoid system, or "mini-brain," for studying sporadic Creutzfeldt-Jakob disease (CJD). CJD is a fatal ...

Medical research

Rheumatoid arthritic pain could be caused by antibodies

Antibodies that exist in the joints before the onset of rheumatoid arthritis can cause pain even in the absence of arthritis, researchers from Karolinska Institutet in Sweden report. The researchers believe that the finding, ...

Medical research

Cell-cell signals in developing heart

During late stages of heart development, interactions between the endocardium (the inner layer of cells) and the myocardium (the heart muscle) are known to be crucial. Signaling between these two cell layers during the earliest ...

Alzheimer's disease & dementia

Modified protein can prevent Alzheimer's disease in mice

The amyloid precursor protein has always been vilified as a major cause of Alzheimer's disease. One of its fragments, the amyloid-beta peptide, can break off and accumulate in the brain, giving rise to the puffy white globs ...

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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.

This text uses material from Wikipedia, licensed under CC BY-SA