Introduction to Medical Biochemistry

 1. Introduction to Enzymes Enzymes are biological catalysts that accelerate biochemical reactions without being consumed during the reaction. Most enzymes are proteins, although some RNA molecules, known as ribozymes, also possess catalytic activity. Enzymes are essential for almost all metabolic processes, including digestion, energy production, protein synthesis, and cellular regulation. Major characteristics of enzymes: They increase the rate of biochemical reactions. They lower the activation energy required for a reaction. They are not consumed during the reaction. They exhibit substrate specificity. They function optimally under specific temperature and pH conditions. Many enzyme-catalysed reactions are reversible. 1.1 Enzyme Nomenclature Enzymes are commonly named by adding the suffix -ase to the substrate or type of reaction they catalyse. Examples: Amylase: breaks down starch. Lipase: breaks down lipids. Protease: breaks down proteins. Lactase: breaks down lactose. Urease...

Part I. Carbohydrates 1.1 Definition and general characteristics Carbohydrates are organic compounds containing carbon, hydrogen, and oxygen. They include simple sugars and complex carbohydrate polymers and serve as energy sources, energy reserves, structural components, and participants in cellular recognition. Many carbohydrates have the approximate empirical formula  (CH2O)n , although this formula does not apply to every carbohydrate. Examples: Glucose, fructose, lactose, sucrose, starch, glycogen, and cellulose. Importance of carbohydrates in the human body Provide energy for cellular activities. Maintain blood glucose availability, particularly for the brain and red blood cells. Store energy as glycogen in the liver and skeletal muscles. Form parts of DNA, RNA, ATP, and other biologically important molecules. Contribute to cell-surface recognition through glycoproteins and glycolipids. Participate in the structure of the extrac...