Corpus: Cell
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This text has been translated by an AI and may sound raw. It will be reviewed shortly. Thank you for your patience!
from Latin: cellula - "small chamber"
English:
Definition[Bearbeiten]
The cell is a fundamental biological organisational unit from which almost all known living organisms are built. Cells are the smallest units of life that are capable of autonomous reproduction and self-preservation.
Background[Bearbeiten]
All known cells, with the exception of some specialised cell types, have certain components in common:
- DNA, the genetic information that serves as the blueprint for the other components of the cell
- Proteins, which are structural proteins or enzymes responsible for the construction and biochemical functions of the cell
- Membranes, which seal the cell off from its environment, act as filters, maintain contact with the outside world and divide more complex cells into compartments
Cells also have common basic abilities:
- Reproduction through cell division
- Metabolism, the uptake of raw material, its conversion into new components and energy, and the disposal of waste products
- Protein biosynthesis through transcription of DNA to RNA and its translation to proteins
Cells are subdivided into prokaryotes, eukaryotes and archaea.
Organisation[Bearbeiten]
The most important structures of a eukaryotic cell are:
- Nucleolus
- Cell nucleus (nucleus)
- Ribosomes
- Vesicles
- Rough endoplasmic reticulum (ER)
- Golgi apparatus
- Microtubules
- Smooth endoplasmic reticulum (SER)
- Mitochondria
- Lysosome
- Cytosol
- Peroxisome
- Centrioles
Cell types[Bearbeiten]
The human body consists of around 220 different cell types that combine to form specific tissues. They can be roughly categorised into somatic cells and gametes, which also go through different cell cycles. Examples are:
Body cells[Bearbeiten]
- Muscle cells
- Epithelial cells
- Ciliated epithelial cells
- Squamous epithelial cells
- Connective tissue cells
- Nerve cells
- Cartilage cells
Germ cells[Bearbeiten]
- Sperm cells
- Oocytes
History of the elucidation of cells[Bearbeiten]
- 1665: Robert Hooke discovers cells first in cork, then in living plants, with the help of the first microscopes
- 1839: Theodor Schwann shows that animals and plants are made up of cells.
- Louis Pasteur disproves the theory that cells can form spontaneously "out of nothing" (generatio spontanea)
- Rudolf Virchow shows that every cell arises from another (omni cellula ex cellula)
see also: Cell biology