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  2. Apoptosis - Wikipedia

    en.wikipedia.org/wiki/Apoptosis

    In contrast to necrosis, which is a form of traumatic cell death that results from acute cellular injury, apoptosis is a highly regulated and controlled process that confers advantages during an organism's life cycle. For example, the separation of fingers and toes in a developing human embryo occurs because cells between the digits undergo ...

  3. Programmed cell death - Wikipedia

    en.wikipedia.org/wiki/Programmed_cell_death

    Programmed cell death ( PCD; sometimes referred to as cellular suicide [1]) is the death of a cell as a result of events inside of a cell, such as apoptosis or autophagy. [2] [3] PCD is carried out in a biological process, which usually confers advantage during an organism's lifecycle. For example, the differentiation of fingers and toes in a ...

  4. Product life-cycle theory - Wikipedia

    en.wikipedia.org/wiki/Product_life-cycle_theory

    Product life-cycle theory. The Product Life Cycle Theory is an economic theory that was developed by Raymond Vernon in response to the failure of the Heckscher–Ohlin model to explain the observed pattern of international trade. The theory suggests that early in a product's life-cycle all the parts and labor associated with that product come ...

  5. Identification of cell death - Wikipedia

    en.wikipedia.org/wiki/Identification_of_cell_death

    The role of cell death is the maintenance of tissue and organ homeostasis, for example, the regular loss of skin cells or a more active role seen in involuting tissues like the thymus. Cells die either by accident or design. In fact there are two mechanisms of cell death; necrosis and apoptosis (apoptosis in invertebrates is called cell ...

  6. Cell death - Wikipedia

    en.wikipedia.org/wiki/Cell_death

    Cell death. Cell death is the event of a biological cell ceasing to carry out its functions. This may be the result of the natural process of old cells dying and being replaced by new ones, as in programmed cell death, or may result from factors such as diseases, localized injury, or the death of the organism of which the cells are part.

  7. Positive feedback - Wikipedia

    en.wikipedia.org/wiki/Positive_feedback

    A number of examples of positive feedback systems may be found in physiology. One example is the onset of contractions in childbirth, known as the Ferguson reflex. When a contraction occurs, the hormone oxytocin causes a nerve stimulus, which stimulates the hypothalamus to produce more oxytocin, which increases uterine contractions.

  8. Biological process - Wikipedia

    en.wikipedia.org/wiki/Biological_process

    Biological processes are made of many chemical reactions or other events that are involved in the persistence and transformation of life forms. [1] 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 ...

  9. Biological life cycle - Wikipedia

    en.wikipedia.org/wiki/Biological_life_cycle

    Reproduction completes and perpetuates the cycle. In biology, a biological life cycle (or just life cycle when the biological context is clear) is a series of stages of the life of an organism, that begins as a zygote, often in an egg, and concludes as an adult that reproduces, producing an offspring in the form of a new zygote which then ...