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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]
The largest reservoir of chlorine resides in the lithosphere, where 2.2 × 10 22 kg of global chlorine is found in Earth's mantle. [2] Volcanic eruptions will sporadically release high levels of chlorine as HCl into the troposphere , but the majority of the terrestrial chlorine flux comes from seawater sources mixing with the mantle.
The Cl–Cl distance is 198 pm (close to the gaseous Cl–Cl distance of 199 pm) and the Cl···Cl distance between molecules is 332 pm within a layer and 382 pm between layers (compare the van der Waals radius of chlorine, 180 pm). This structure means that chlorine is a very poor conductor of electricity, and indeed its conductivity is so ...
The term chloride refers to a compound or molecule that contains either a chlorine anion (Cl −), which is a negatively charged chlorine atom, or a non-charged chlorine atom covalently bonded to the rest of the molecule by a single bond (−Cl). The pronunciation of the word "chloride" is / ˈ k l ɔːr aɪ d /. [3]
The structure of these channels are not like other known channels. The chloride channel subunits contain between 1 and 12 transmembrane segments. Some chloride channels are activated only by voltage (i.e., voltage-gated), while others are activated by Ca 2+ , other extracellular ligands, or pH.
Choline is a cation with the chemical formula [(CH 3) 3 NCH 2 CH 2 OH] +. [1] [2] [3] Choline forms various salts, such as choline chloride and choline bitartrate.An essential nutrient for animals, it is a structural component of phospholipids and cell membranes.
Structures comparing porphin, chlorin, bacteriochlorin, and isobacteriochlorin. Microbes produce two reduced variants of chlorin, bacteriochlorins and isobacteriochlorins. Bacteriochlorins are found in some bacteriochlorophylls; the ring structure is produced by Chlorophyllide a reductase (COR) reducing a chlorin ring at the C7-8 double boud.