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Proteins and chemical tests GapFill

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Inorganic ions in the cytoplasm of cells and in body fluids play important roles in the body. For example:

  •  nitratephosphatehydrogenammonium ions determine the pH of solutions and are important in photosynthesis and respiration
  •  sodiumhydroxidenitratechloride ions are involved in regulating osmotic pressure, muscle contraction and co-transport of glucose in the intestine
  •  phosphateammoniumhydroxidenitrate ions are important in the nitrogen cycle and are an essential part of nucleic acid
  •  calciumhydrogenchlorideammonium ions have far-reaching roles in regulating haemoglobin's affinity for oxygen, forming acid in the stomach and maintaining water balance

  • Amino acids are the monomers which form proteins. They all have the same basic structure of an amine group and  a phosphatean alcoholan alkenea carboxyl group, but they differ in their R groups, or side chains. Polypeptides are formed by  condensationmultiplicationreductionhydrolysis reactions, where many amino acids form a chain linked by  peptideglycosidichydrogendouble bonds. This sequence of amino acids is known as the primary structure. Interactions between slightly positive H atoms and slightly negative atoms (usually O or N) are called  ionic bondssulfide bondsdiphobic bondshydrogen bonds, and these result in a chain twisting into  a peptide plaita double helixan alpha helixan omega spring or a beta-pleated sheet, which is the secondary structure. Further twisting and folding into the tertiary structure can occur as a result of ionic bonds,  disulfide bondscarbon pathsamino bondscovalent tunnels and hydrophobic or hydrophilic interactions, and sometimes more than one polypeptide chain may come together as the  quaternary structurefourth sequencecombinatory peptide formfinal form of the molecule. For example, insulin is a  anionicglobularhydrophobicfibrous protein consisting of two chains forming a roughly spherical shape.

    The chemical test for  glucosereducing sugarsnucleic acidsproteins is called the biuret test.  Reducing sugarsNon-reducing sugarsLipidsProteins can be identified with a positive result of the emulsion test. Meanwhile, starch can be detected using  iodinecopper (II) sulfateBenedict's reagenthydrochloric acid.

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    Pass Mark
    72%