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  2. Octet rule - Wikipedia

    en.wikipedia.org/wiki/Octet_rule

    The octet rule is a chemical rule of thumb that reflects the theory that main-group elements tend to bond in such a way that each atom has eight electrons in its valence shell, giving it the same electronic configuration as a noble gas. The rule is especially applicable to carbon, nitrogen, oxygen, and the halogens; although more generally the ...

  3. Biomolecule - Wikipedia

    en.wikipedia.org/wiki/Biomolecule

    A biomolecule or biological molecule is loosely defined as a molecule produced by a living organism and essential to one or more typically biological processes. [1] Biomolecules include large macromolecules such as proteins, carbohydrates, lipids, and nucleic acids, as well as small molecules such as vitamins and hormones.

  4. Adenosine triphosphate - Wikipedia

    en.wikipedia.org/wiki/Adenosine_triphosphate

    Interactive animation of the structure of ATP. Adenosine triphosphate (ATP) is a nucleoside triphosphate [ 2 ] that provides energy to drive and support many processes in living cells, such as muscle contraction, nerve impulse propagation, and chemical synthesis.

  5. Abiogenesis - Wikipedia

    en.wikipedia.org/wiki/Abiogenesis

    Life functions through the specialized chemistry of carbon and water, and builds largely upon four key families of chemicals: lipids for cell membranes, carbohydrates such as sugars, amino acids for protein metabolism, and nucleic acid DNA and RNA for the mechanisms of heredity.

  6. Nicotinamide adenine dinucleotide - Wikipedia

    en.wikipedia.org/wiki/Nicotinamide_adenine_di...

    Found in all living cells, NAD is called a dinucleotide because it consists of two nucleotides joined through their phosphate groups. One nucleotide contains an adenine nucleobase and the other, nicotinamide. NAD exists in two forms: an oxidized and reduced form, abbreviated as NAD+ and NADH (H for hydrogen), respectively.

  7. Terpene - Wikipedia

    en.wikipedia.org/wiki/Terpene

    Terpenes (/ ˈtɜːrpiːn /) are a class of natural products consisting of compounds with the formula (C 5 H 8) n for n ≥ 2. Terpenes are major biosynthetic building blocks. Comprising more than 30,000 compounds, these unsaturated hydrocarbons are produced predominantly by plants, particularly conifers. [1][2][3] In plants, terpenes and ...

  8. Chlorophyll - Wikipedia

    en.wikipedia.org/wiki/Chlorophyll

    Chlorophyll is bound to proteins. Protochlorophyllide, one of the biosynthetic intermediates, occurs mostly in the free form and, under light conditions, acts as a photosensitizer, forming free radicals, which can be toxic to the plant. Hence, plants regulate the amount of this chlorophyll precursor.

  9. One gene–one enzyme hypothesis - Wikipedia

    en.wikipedia.org/wiki/One_gene–one_enzyme...

    [3] The development of the one gene–one enzyme hypothesis is often considered the first significant result in what came to be called molecular biology. [4] Although it has been extremely influential, the hypothesis was recognized soon after its proposal to be an oversimplification. Even the subsequent reformulation of the "one gene–one ...