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  2. Cell (biology) - Wikipedia

    en.wikipedia.org/wiki/Cell_(biology)

    Structure of a typical prokaryotic cell. Prokaryotes include bacteria and archaea, two of the three domains of life. Prokaryotic cells were the first form of life on Earth, characterized by having vital biological processes including cell signaling. They are simpler and smaller than eukaryotic cells, and lack a nucleus, and other membrane-bound ...

  3. Plant cell - Wikipedia

    en.wikipedia.org/wiki/Plant_cell

    Structure of a plant cell. Plant cells are the cells present in green plants, photosynthetic eukaryotes of the kingdom Plantae.Their distinctive features include primary cell walls containing cellulose, hemicelluloses and pectin, the presence of plastids with the capability to perform photosynthesis and store starch, a large vacuole that regulates turgor pressure, the absence of flagella or ...

  4. Bacterial cell structure - Wikipedia

    en.wikipedia.org/wiki/Bacterial_cell_structure

    Therefore, a typical fully grown 1-liter culture of Escherichia coli (at an optical density of 1.0, corresponding to c. 10 9 cells/ml) yields about 1 g wet cell mass. [2] Small size is extremely important because it allows for a large surface area-to-volume ratio which allows for rapid uptake and intracellular distribution of nutrients and ...

  5. Cell wall - Wikipedia

    en.wikipedia.org/wiki/Cell_wall

    Diagram of the plant cell, with the cell wall in green. Cell walls serve similar purposes in those organisms that possess them. They may give cells rigidity and strength, offering protection against mechanical stress. The chemical composition and mechanical properties of the cell wall are linked with plant cell growth and morphogenesis. [11]

  6. Cell nucleus - Wikipedia

    en.wikipedia.org/wiki/Cell_nucleus

    Diagram of the nucleus showing the ribosome-studded outer nuclear membrane, nuclear pores, DNA (complexed as chromatin), and the nucleolus. The nucleus contains nearly all of the cell's DNA, surrounded by a network of fibrous intermediate filaments called the nuclear matrix, and is enveloped in a double membrane called the nuclear envelope.

  7. Cell cycle - Wikipedia

    en.wikipedia.org/wiki/Cell_cycle

    The eukaryotic cell cycle consists of four distinct phases: G 1 phase, S phase (synthesis), G 2 phase (collectively known as interphase) and M phase (mitosis and cytokinesis). M phase is itself composed of two tightly coupled processes: mitosis, in which the cell's nucleus divides, and cytokinesis, in which the cell's cytoplasm and cell membrane divides forming two daughter cells.

  8. Prokaryote - Wikipedia

    en.wikipedia.org/wiki/Prokaryote

    Diagram of a typical prokaryotic cell. A prokaryote (/ proʊˈkærioʊt, - ət /, less commonly spelled procaryote) [1] is a single-cell organism whose cell lacks a nucleus and other membrane -bound organelles. [2]

  9. Neuron - Wikipedia

    en.wikipedia.org/wiki/Neuron

    Diagram of a typical myelinated vertebrate motor neuron Neurology video. Axons and dendrites in the central nervous system are typically only about one micrometer thick, while some in the peripheral nervous system are much thicker. The soma is usually about 10–25 micrometers in diameter and often is not much larger than the cell nucleus it ...