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  2. Biological roles of the elements - Wikipedia

    en.wikipedia.org/wiki/Biological_roles_of_the...

    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]

  3. Composition of the human body - Wikipedia

    en.wikipedia.org/wiki/Composition_of_the_human_body

    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 ...

  4. Nutrition - Wikipedia

    en.wikipedia.org/wiki/Nutrition

    Human behavior is closely related to human nutrition, making it a subject of social science in addition to biology. Nutrition in humans is balanced with eating for pleasure, and optimal diet may vary depending on the demographics and health concerns of each person. [37] Humans are omnivores that eat a variety of foods.

  5. Biochemistry - Wikipedia

    en.wikipedia.org/wiki/Biochemistry

    Just six elements—carbon, hydrogen, nitrogen, oxygen, calcium and phosphorus—make up almost 99% of the mass of living cells, including those in the human body (see composition of the human body for a complete list). In addition to the six major elements that compose most of the human body, humans require smaller amounts of possibly 18 more ...

  6. Human nutrition - Wikipedia

    en.wikipedia.org/wiki/Human_nutrition

    Vitamins and minerals are essential to the proper functioning and maintenance of the human body. [114] There are 20 trace elements and minerals that are essential in small quantities to body function and overall human health. [114] Iron deficiency is the most common inadequate nutrient worldwide, affecting approximately 2 billion people. [115]

  7. Roles of chemical elements - Wikipedia

    en.wikipedia.org/wiki/Roles_of_chemical_elements

    Element Per. Gr. Role(s) in nature (non-living and living) Role(s) in technology (old and new) 1: H: Hydrogen 1 1: Astronomy: source of power by nuclear fusion (proton–proton chain reaction and CNO cycle) Biology: One of the most common elements in living organisms: Petrochemical industry: hydrodealkylation, hydrodesulfurization

  8. Iron in biology - Wikipedia

    en.wikipedia.org/wiki/Iron_in_biology

    The human body's rate of iron absorption appears to respond to a variety of interdependent factors, including total iron stores, the extent to which the bone marrow is producing new red blood cells, the concentration of hemoglobin in the blood, and the oxygen content of the blood.

  9. CHNOPS - Wikipedia

    en.wikipedia.org/wiki/CHNOPS

    Graphic representation of carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur. CHNOPS and CHON are mnemonic acronyms for the most common elements in living organisms. . "CHON" stands for carbon, hydrogen, oxygen, and nitrogen, which together make up more than 95 percent of the mass of biological system