Search results
Results from the WOW.Com Content Network
Cells can be up to 10 cm long, and are separated by a small septum. [17] Small holes in the septum allow cytoplasm and cytoplasmic contents to flow from cell to cell. Osmotic pressure gradients occur through the length of the cell to drive this cytoplasmic flow. Flows contribute to growth and the formation of cellular subcompartments. [17] [18]
The cell is the basic structural and functional unit of all forms of life. Every cell consists of cytoplasm enclosed within a membrane; many cells contain organelles, each with a specific function. The term comes from the Latin word cellula meaning 'small room'. Most cells are only visible under a microscope.
Light micrograph of a moss's leaf cells at 400X magnification. The following outline is provided as an overview of and topical guide to cell biology: . Cell biology – A branch of biology that includes study of cells regarding their physiological properties, structure, and function; the organelles they contain; interactions with their environment; and their life cycle, division, and death.
Their functions include establishing a resting membrane potential, [1] shaping action potentials and other electrical signals by gating the flow of ions across the cell membrane, controlling the flow of ions across secretory and epithelial cells, and regulating cell volume. Ion channels are present in the membranes of all cells.
The flow of cytoplasmic components plays an important role in many cellular functions which are dependent on the permeability of the cytoplasm. [8] An example of such function is cell signalling , a process which is dependent on the manner in which signaling molecules are allowed to diffuse across the cell. [ 9 ]
In biology, cell signaling (cell signalling in British English) is the process by which a cell interacts with itself, other cells, and the environment. Cell signaling is a fundamental property of all cellular life in prokaryotes and eukaryotes. Typically, the signaling process involves three components: the signal, the receptor, and the effector.
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.
Regulation of biological processes occurs when any process is modulated in its frequency, rate or extent. Biological processes are regulated by many means; examples include the control of gene expression, protein modification or interaction with a protein or substrate molecule.