carbohydrates & lipids depth

• Monomers are individual subunits that can be joined together to form large chains called polymers
• Starch is the storage polymer of plants, consisting of amylose (unbranched) and amylopectin (branched).
• the breaking down of molecules is called hydrolysis
• in hydrolysis, water molecules are used to break down the covalent bonds between the monomers that make a polymer
• condensation is the joining of molecules
• monosaccharides:

  • the same number of C and O atoms
  • white crystalline solids
  • dissolve in water into sweet-tasting solutions
• glucose forms the base unit for many polymers
• Galactose:

  • usually found in milk or cereals
  • less sweet than glucose
• fructose:

  • pentose sugar
  • found in fruits and honey
  • sweetest naturally occurring carbohydrate
• Ribose:

  • pentose sugar
  • forms the backbone of RNA
• When 2 Monosaccharide link together they make a Disaccharide, this is a condensation reaction
• Condensation Reactions involve the formation of a glycosidic bond to join the 2 monosaccharides
• Lactose:

  • Most commonly found in milk
• iodine solution: turns blue-black if starch is present
• Benedict solution: add benedicts to the solution, heat it and wait for a colour change. If sugar is present it turns brick red, if less sugar is present it turns yellow/green
• Biuret: test for proteins, if present the solution turns purple
• Ethanol: add ethanol to the solution and shake, see if there is any colour change. if there is fat present, the solution will turn cloudy
• starch:

  • long chain of a-glucose molecules
  • Insoluble due to its structure
  • main plant storage
  • found in chloroplasts
• glycogen:

  • Found in the liver and muscle cells
  • Insoluble compact store of glucose in animals
  • α-glucose units