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Representative lifetimes of stars as a function of their masses The change in size with time of a Sun-like star Artist's depiction of the life cycle of a Sun-like star, starting as a main-sequence star at lower left then expanding through the subgiant and giant phases, until its outer envelope is expelled to form a planetary nebula at upper right Chart of stellar evolution
Biological life 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 itself goes through the same ...
Cryogenian ice age. Ediacaran biota. Cambrian explosion. Andean glaciation. Earliest tetrapods. Karoo ice age. Earliest apes humans. Quaternary ice age. The timeline of the evolutionary history of life represents the current scientific theory outlining the major events during the development of life on planet Earth.
Enterprise life cycle, the process of changing a business enterprise. Project life cycle. Product lifecycle, the stages in the lifespan of a commercial or consumer product. New product development, the process of bringing a new product to market. Life-cycle assessment, the analysis of the environmental impacts associated with a product.
In astronomy, the main sequence is a classification of stars which appear on plots of stellar color versus brightness as a continuous and distinctive band. Stars on this band are known as main-sequence stars or dwarf stars, and positions of stars on and off the band are believed to indicate their physical properties, as well as their progress ...
Alternation of generations (also known as metagenesis or heterogenesis) [1] is the predominant type of life cycle in plants and algae. In plants both phases are multicellular: the haploid sexual phase – the gametophyte – alternates with a diploid asexual phase – the sporophyte . A mature sporophyte produces haploid spores by meiosis, a ...
It is a relatively short period of the cell cycle. M phase is complex and highly regulated. The sequence of events is divided into phases, corresponding to the completion of one set of activities and the start of the next. These phases are sequentially known as: prophase; prometaphase; metaphase; anaphase; telophase; A diagram of the mitotic phases
Stellar nucleosynthesis. In astrophysics, stellar nucleosynthesis is the creation of chemical elements by nuclear fusion reactions within stars. Stellar nucleosynthesis has occurred since the original creation of hydrogen, helium and lithium during the Big Bang. As a predictive theory, it yields accurate estimates of the observed abundances of ...