At pH values between the two pKa values, the zwitterion predominates, but coexists in dynamic equilibrium with small amounts of net negative and net positive ions. At the exact midpoint between the tw ...
The amine and carboxylic acid functional groups found in amino acids allow them to have amphiprotic properties. Carboxylic acid groups (?CO2H) can be deprotonated to become negative carboxylates (?C ...
Of the standard α-amino acids, all but glycine can exist in either of two enantiomers, called L or D amino acids, which are mirror images of each other (see also Chirality). While L-amino acids repre ...
In the structure shown at the top of the page, R represents a side-chain specific to each amino acid. The carbon atom next to the carboxyl group is called the α–carbon and amino acids with a side-ch ...
The first few amino acids were discovered in the early 19th century. In 1806, French chemists Louis-Nicolas Vauquelin and Pierre Jean Robiquet isolated a compound in asparagus that was subsequently na ...
Amino acids (/??mi?no?/, /??ma?no?/, or /??m?no?/) are biologically important organic compounds composed of amine (-NH2) and carboxylic acid (-COOH) functional groups, along with a side-ch ...
Recent studies have shown a tight linkage between living organisms and chemical elements on this planet. This led to the redefinition of minerals as "an element or compound, amorphous or crystalline, ...
Many elements have been suggested as essential, but such claims have usually not been confirmed. Definitive evidence for efficacy comes from the characterization of a biomolecule containing the elemen ...
Dietitians may recommend that dietary elements are best supplied by ingesting specific foods rich with the chemical element(s) of interest. The elements may be naturally present in the food (e.g., cal ...
Dietary elements are present in a healthy human being's blood at certain mass and molar concentrations. The figure below presents the concentrations of each of the dietary elements discussed in this a ...
Some sources state that sixteen chemical elements are required to support human biochemical processes by serving structural and functional roles as well as electrolytes: However, as many as 26 element ...
Dietary elements (commonly known as dietary minerals or mineral nutrients) are the chemical elements required by living organisms, other than the four elements carbon, hydrogen, nitrogen, and oxygen p ...
Other agents purported to have nootropic effects but do not (yet) have attributable mechanisms or clinically significant effects (but may upon refinement of administration) are listed below.Nootropics ...
These are hormones that have activity not necessarily attributable to another specific chemical interaction, but have shown effectiveness. Only specific nootropic effects are stated.Vasopressin—memor ...
Nerves are necessary to the foundation of brain communication and their degeneracy, underperformance, or lacking can have disastrous results on brain functions. Antioxidants may prevent oxidative stre ...
