Biomedical technology

3D lab skin for chemicals testing, research and repair

A model system that recreates full-thickness human skin should allow more effective testing of pharmaceuticals and cosmetics, while avoiding the need for animal tests. The system effectively models the development, cellular ...

Medical research

Putting a protein into overdrive to heal spinal cord injuries

Using genetic engineering, researchers at UT Southwestern and Indiana University have reprogrammed scar-forming cells in mouse spinal cords to create new nerve cells, spurring recovery after spinal cord injury. The findings, ...

Medical research

How bone marrow regenerates after chemotherapy

Chemotherapy has a damaging effect on hematopoietic stem and progenitor cells (HSPCs) in bone marrow. However, once chemotherapy ends, HSPCs regenerate, a process that has remained unknown—until now. In a new study, researchers ...

Diseases, Conditions, Syndromes

COVID-19: Biomarkers linked to severe forms of the disease

Recent studies have shown that immune response plays a central role in the severity of COVID-19. Understanding the immune responses generated as the disease progresses is therefore key to determining which patients are at ...

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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