Science: Organic Compounds

• Protein
• Most abundant organic compound
• Fundamental structural and functional frameworks of the cell’s protoplasm
• Kinds:
• Structural/Fibrous protein – build and repair body cell tissues
• Globular/Enzymatic protein – biological catalyst in almost every chemical reaction
• Nucleic acid
• DNA and RNA
• Carbohydrates
• Chief energy source
• Backbone of molecules
• When combined with protein, they form glycoproteins and proteoglycans
• Classifications:
• Monosaccharide – simple sugar which serves as building blocks for more complex forms like glucose, fructose, galactose
• Disaccharides – formed by chemical combination of 2 monosaccharides but with removal of water molecules (like maltose, sucrose, lactose)
• Polysaccharide – series of monosaccharides
• Starch – serves as units of glucose
• Glycogen – stored carbohydrates found in animals
• Cellulose – insoluble carbohydrate; abundant in the tough outer wall of plant cells
• Chitin – exoskeleton of animals
• Lipids
• Fats and oils
• Served as the highest source of energy
• Acts as insulator protecting animals from extreme cold
• Contributes to the cell membrane semi-permeability(as phospholipids)
• Building blocks for many steroids
• Classifications:
• Neutral – major fuels for animals; saturated (cholesterol); unsaturated
• Phospholipids – biological component in the plasma membrane
• Sphingolipids – maintain the right shape of organs and tissues
• Waxes – example: polishers, ointments and lubricants
• Steroid – complex units of alcohol
• Cholesterol
• Sex hormones
• Bile salt (emulsifier of fats)