Search results
Results From The WOW.Com Content Network
The oxygen cycle is the biogeochemical cycle of oxygen atoms between different oxidation states in ions, oxides, and molecules through redox reactions within and between the spheres/reservoirs of the planet Earth. [ 1] The word oxygen in the literature typically refers to the most common oxygen allotrope, elemental/diatomic oxygen (O 2 ), as it ...
Photosynthesis ( / ˌfoʊtəˈsɪnθəsɪs / FOH-tə-SINTH-ə-sis) [ 1] is a system of biological processes by which photosynthetic organisms, such as most plants, algae, and cyanobacteria, convert light energy, typically from sunlight, into the chemical energy necessary to fuel their metabolism.
Nutrient. A nutrient is a substance used by an organism to survive, grow and reproduce. The requirement for dietary nutrient intake applies to animals, plants, fungi and protists. Nutrients can be incorporated into cells for metabolic purposes or excreted by cells to create non-cellular structures such as hair, scales, feathers, or exoskeletons.
The tables below include tabular lists for selected basic foods, compiled from United States Dept. of Agriculture ( USDA) sources. Included for each food is its weight in grams, its calories, and (also in grams,) the amount of protein, carbohydrates, dietary fiber, fat, and saturated fat. [ 1] As foods vary by brands and stores, the figures ...
Oxygen began building up in the atmosphere at approximately 1.85 Ga. At current rates of primary production, today's concentration of oxygen could be produced by photosynthetic organisms in 2,000 years. [ 4] In the absence of plants, the rate of oxygen production by photosynthesis was slower in the Precambrian, and the concentrations of O 2 ...
In the context of nutrition, a mineral is a chemical element. Some "minerals" are essential for life, but most are not. [ 1][ 2][ 3] Minerals are one of the four groups of essential nutrients; the others are vitamins, essential fatty acids, and essential amino acids. [ 4] The five major minerals in the human body are calcium, phosphorus ...
O. have also been characterized, all short-lived. The longest-lived radioisotope is 15. O. with a half-life of 122.266 (43) s, while the shortest-lived isotope is the unbound 11. O. with a half-life of 198 (12) yoctoseconds, though half-lives have not been measured for the unbound heavy isotopes 27. O. and 28.
Scientists have discovered a new source of oxygen on the planet, originating from metal “batteries” deep beneath the Pacific Ocean. The “dark oxygen” phenomenon was observed at depths of ...