carbohydrates & lipids

• macromolecules are large molecules made of monomers
• 4 macromolecule classes: carbohydrates, lipids, proteins and nucleic acid
• hydrolysis is the process of breaking down macromolecules into monomers
• hydrolysis is a reverse reaction
• condensation and hydrolysis are reverse processes that can create and breakdown polymers
• carbohydrates contain H and O atoms in a 2:1 ratio (glucose)
• lipids contain less oxygen than carbohydrates (oleic acid)
• monosaccharides = 1 monomer
• disaccharides = 2 monomers joined
• polysaccharides = long chain of monomers (3 or more)
• monosaccharides: glucose, galactose, fructose, ribose
• Maltose = glucose + Glucose
• when 2 monomers link together they become a disaccharide
• disaccharides: maltose, lactose, sucrose
• lactose = glucose + galactose
• sucrose = glucose + fructose
• all monosaccharides are reducing sugars, some disaccharides are reducing sugars
• reducing sugars means they can donate electrons to another chemical
• reducing sugars: glucose, fructose, galactose, maltose, lactose
• non-reducing sugars: sucrose
• if you were to test for reducing sugars, you would need the benedict test by heating and then adding the benedict solution (turns yellow to green)
• 3 important polysaccharides: starch, cellulose and glycogen
• polysaccharides are formed by disaccharides and are used as energy stores
• starch: mixture of amylose and amyloceptin
• 2 types of polysaccharides in starch: amylose (linear chain of glucose) and amylopectin (highly branched chain of glucose)
• starch is the main store in plants
• glycogen- energy storage in animals
• types of lipids: triglycerides, phospholipids and steroids
• lipids are hydrophobic and do not dissolve in water
• lipids are sources of energy storage
• myelin sheat serves for insulation (temp regulation)
• lipids act as hormones
• carbohydrates & lipids: carbon, hydrogen, oxygen
• proteins: carbon, hydrogen, oxygen, nitrogen
• nucleic acids: carbon, hydrogen, oxygen, nitrogen, phosphorus
• triglyceride: glycerol and 3 fatty acids. serves as an energy store, stored as fat for thermal insulation
• phospholipid: glycerol + 2 fatty acids and a phosphate group,

  • part hydrophilic, part hydrophobic (ideal for membranes)
• cholesterol:

  • 4 carbon-based ring structures joined together
  • forms small molecule that fits a lipid bilayer, contributes to strength and stability