All of the following are true EXCEPT
Analyse each option:- Nutritionally non-essential amino acids can be synthesised in the body. So, their absence from the diet in proteins is not deleterious to human health - option a is correct statement. Selenocysteine is present in Thioredoxin reductase, Glutathione peroxidase, 5' deiodinase, Selenoprotein P - option c is correct statement. Oxaloacetate and alpha ketoglutarate are precursors of aspaate and glutamate. 3-phosphoglycerate is the precursor of serine which in turn can produce glycine - option d is also correct. We are left with option b. Tetrahydrobiopterin is needed for tyrosine biosynthesis, not for tryptophan. Moreover, tryptophan cannot be synthesized in human body!
Absence from the diet of ceain amino acids that are present in most proteins is not deleterious to human health
Tetrahydrobiopterin is involved in tryptophan biosynthesis
Selenocysteine is an essential component of several mammalian proteins
Intermediates of the citric acid cycle and of glycolysis acts as precursors of aspaate, asparagine, glutamate, glutamine, glycine, and serine
Classification and metabolism of amino acids