Lipids

• what do lipids include

  • triglycerides
  • phospholipids
• what are the 3 elements lipids are made up of

  • carbon
  • hydrogen
  • oxygen
• what makes lipids different from carbohydrates although they are made up of the same elements

  lipids have less oxygen
• what is the chemical formula of lipids

  • COOH(CH2)nCH3
• what does hydrophilic mean

  water loving
• what does hydrophobic mean

  water hating
• what are the 2 main components that make up triglycerides

  • glycerol
  • fatty acids
• why are triglycerides not polymers

  • made up of 2 different types of subunits
  • (glycerol + fatty acids)
  • which have different structures
  • so not identical monomers
• what is glycerol

  • alcohol
  • formula = C3H803
• what are the 6 functions of lipids within living organisms

  • energy storage
  • protection of vital organs
  • buoyancy
  • metabolic water
  • waterproofing
• how does energy store help

  • used in seeds + animals
  • as they release more energy than carbohydrates when used as alternative respiratory substrates
• how does lipids help with protecting organs

  • used as 'shock absorption'
  • prevents physical damage
• how does lipids help with thermal insulation

  • used as thermal insulator
  • eg. blubber in whales
• how does lipids help with buoyancy

  • lipids less dense than water so float
• how does lipids help with metabolic water

  • production of metabolic water when lipids are oxidised by respiration
  • eg. camels who have fat in humps + live in deserts
• how does lipids help with waterproofing

  • waxes are hydrophobic -> covers exoskeleton of insects + cuticle of plant leaves
  • provide waterproofing + reduce water loss