The physiology of the amino acids / by Frank P. Underhill.

  • Frank Pell Underhill
Date:
1915
Catalogue details

Licence: In copyright

Credit: The physiology of the amino acids / by Frank P. Underhill. Source: Wellcome Collection.

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    THE PROTEINS AND THEIR DERIVATIVES— THE AMINO ACIDS The Proteins The presence of nitrogen as a fundamental con- stituent of protoplasm attests the supreme importance of this element for the construction of living matter and the continued existence of organized life. It is well recognized, however, that all forms of nitrogen are not equally available for the maintenance of physiological rhythm. In support of this may be cited the fact that although the animal organism is con- tinually surrounded by an atmosphere rich in nitrogen, little or none of this nitrogen can be utilized by the body for nutritional purposes. The organism pos- sesses discriminating powers and demands nitrogen in a specific form, namely, such as that peculiar to protein and its derivatives. Protein material con- stitutes therefore an essential foodstufif and without it life would be impossible for any considerable period of time. “It is the chemical nucleus or pivot around which revolves a multitude of reactions characteristic of biological phenomena.”