Easy Biochemistry Notes

Definition - Biomarkers that are indicators of liver dysfunction Tests used for diagnosing & monitoring of liver diseases. Classification -  I.    TESTS BASED ON EXCRETORY FUNCTION 1.SERUM BILIRUBIN-  The main excretory product of liver is bile. It is formed and stored in liver. Normal plasma bilirubin -   Total bilirubin - 0.2–0.8 mg/ dL. Unconjugated Bilirubin is about 0.2–0.6 mg/dL, Conjugated Bilirubin is about 0–0.2 mg/dL . A.Tests to assess serum bilirubin  - VandenBergh Reaction Procedure - Bilirubin reacts with diazo reagent (diazotized sulfanilic acid) to produce colored azo pigment. At pH 5, the pigment is purple in color. Conjugated bilirubin, being water soluble gives the color immediately; hence called Direct reaction. Unconjugated bilirubin is water insoluble. It has to be extracted first with alcohol, and then the reaction becomes positive; hence called Indirect reaction. If both conjugated and unconjugated bilirubin are present in inc...

Steps in the Formation of Collagen - 1.Intracellular Steps 2.Extracellular steps INTRACELLULAR STEPS 1.Translation on Ribosome -  synthesized by fibroblasts Inside the fibroblasts translation of Gly-X-Y repeat sequence occurs at the rough ER  Intracellularly it is secreted as a precursor- Pre-Procollagen POST - TRANSLATIONAL MODIFICATIONS  -   all the next steps are considered as post translational modifications. they convert pre-procollagen into mature collagen. 2.Hydroxylation of Proline & Lysine - Hydroxylation of proline at position 4 & lysine at position 5 with prolyl hydroxylase and lysyl hydroxylase(dioxygenase enzymes) using molecular oxygen. These enzymes contain Fe2+ ion at their active site and require Vitamin C to preserve ion in reduced ferrous state. Vitamin C deficiency leads to poor hydroxylation and is the major defect seen in scurvy. 2.Glycosylation of hydroxylation residues- After hydroxylation there is glycosylation with galactose & gl...

Definition: Compound lipids that contain fatty acid, glycerol, or any other alcohol, phosphoric acid residue, and the nitrogenous base is called Phospholipids. Phospholipids are amphipathic, i.e., they have both hydrophobic and hydrophilic portions in their molecule. Glycerol, Phosphoric Acid, And Choline form the hydrophilic polar head. Hydrocarbon Chains Of Fatty Acids form the hydrophobic non-polar tail. Enzymes hydrolyzing phospholipids are called phospholipases.     Classification: on the type of alcohol present, Phospholipids can be classified into two groups I.Glycerophospholipids: Glycerol is the alcohol Made of glycerol + 2 fatty acids + phosphoric acid + nitrogenous base An ester linkage links the two fatty acids to glycerol– C1 carbon contains saturated fatty acid, and C2 carbon contains unsaturated fatty acid. NITROGEN CONTAINING PHOSPHOLIPIDS a)  1. Phosphatidyl Choline (Lecithin): Made of glycerol+ fatty acids + phosphoric acid + choline(ni...