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Parts-per-million cube of relative abundance by mass of elements in an average adult human body down to 1 ppm. About 99% of the mass of the human body is made up of six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus. Only about 0.85% is composed of another five elements: potassium, sulfur, sodium, chlorine, and magnesium ...
A large fraction of the chemical elements that occur naturally on the Earth's surface are essential to the structure and metabolism of living things. Four of these elements (hydrogen, carbon, nitrogen, and oxygen) are essential to every living thing and collectively make up 99% of the mass of protoplasm. [1]
Metabolic water refers to water created inside a living organism through metabolism, by oxidizing energy-containing substances in food and adipose tissue. Animal metabolism produces about 107–110 grams of water per 100 grams of fat , [ 1 ] 41–42 grams of water per 100 g of protein , and 60 grams of water per 100 g of carbohydrate .
Metabolism (/ m ə ˈ t æ b ə l ɪ z ə m /, from Greek: μεταβολή metabolē, "change") is the set of life-sustaining chemical reactions in organisms.The three main functions of metabolism are: the conversion of the energy in food to energy available to run cellular processes; the conversion of food to building blocks of proteins, lipids, nucleic acids, and some carbohydrates; and the ...
Aerobic respiration requires oxygen (O 2) in order to create ATP.Although carbohydrates, fats and proteins are consumed as reactants, aerobic respiration is the preferred method of pyruvate production in glycolysis, and requires pyruvate to the mitochondria in order to be oxidized by the citric acid cycle.
Chemoorganotrophs are organisms which use the chemical energy in organic compounds as their energy source and obtain electrons or hydrogen from the organic compounds, including sugars (i.e. glucose), fats and proteins. [2] Chemoheterotrophs also obtain the carbon atoms that they need for cellular function from these organic compounds.
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. Any successful theory of abiogenesis must explain the origins and ...
Purines are biologically synthesized as nucleotides and in particular as ribotides, i.e. bases attached to ribose 5-phosphate.Both adenine and guanine are derived from the nucleotide inosine monophosphate (IMP), which is the first compound in the pathway to have a completely formed purine ring system.