<prompt> Biuret test is used for detection of:ProteinCholesterolSteroidSugar  <response>: Ans: a Protein Ref: Vasudevan 4th edp.23, 24. 34.Biuret reaction:- Cupric ions chelate with peptide bonds of proteins in alkaline medium to produce a pink or violet colour. This needs a minimum of two peptide bonds and so individual amino acids and dipeptides will not answer this test. Biuret reagent - CuS04, sodium potassium tartarate and potassiumiodide in sodium hydroxide. The intensity of colour is directly proportional to the peptide bonds and is estimated colourimetrically.Other tests:Fouchetstest-Bile pigmentsHays sulphur test- Bile saltsBenedicts test- Blood sugarRotheras test- Ketone bodiesReagentsEhrlichs aldehyde - Porphobilinogen and UrobilinogenFouchets reagent - Bile pigmentBenedicts reagent - GlucoseSodium nitroprusside - Ketones 