Please enable JavaScript.

Coggle requires JavaScript to display documents.

Lipids and Membranes - Coggle Diagram

- - - - They can dissolve into the lipid bilayer and diffuse down the concentration gradient
  - - - Using carrier proteins
        
        These carrier proteins are specific to a certain chemical
        
        In the presence of this specific molecule, the protein will change shape and transport the molecules across the membrane
      - Using channel proteins
        
        These are channels which are specific to a certain chemical or molecule
        
        They are hydrophilic and allow lipid-insoluble molecules, slightly polar molecules and slightly larger molecules to diffuse through
  - - - The energy (ATP) is used to bind to the carrier protein and cause a conformational change to its structure to allow the molecule to be transported
  - - - endocytosis
        
        The process by which a cell membrane engulfs materials by forming a vesicle around it to move them into the cell
      - exocytosis
        
        The process by which materials are removed from the cell through secretory vesicles binding to the cell surface membrane
- - - - The molecule consists of one glycerol head and three fatty acid tails
      - glycerol
        
        A molecule which consists of three carbon atoms joined to 5 hydrogen atoms and 3 -OH groups
        
        It is an alcohol due to the 3 free -OH groups
      - fatty acids
        
        Molecules with a carboxyl group (-COOH) on one end, attached to a hydrocarbon tail
        
        The hydrocarbon tail is made of only hydrogen and carbon
        
        The carboxyl group ionises into H+ ions and a -COO group meaning that the molecule is an acid
      - ester bonds
        
        These are covalent bonds formed between the -COOH group of the fatty acid and the -OH group of a glycerol
        
        They are formed during condensation reaction so release water when the bond is created
    - - Energy source
        
        They can be broken down and used as a secondary source for energy during respiration
      - Energy store
        
        They re insoluble in water and do not affect the water potential of the cell so can be used as storage
        
        They release a higher proportion of hydrogen and carbon atoms but hardly any oxygen so they release 2x energy than glucose
      - Insulation
        
        The lipids can be stored in tissue and acts as an electrical insulator to keep heat closer to the body’s core
      - Buoyancy
        
        Less dense than water so can be used to help stay afloat (especially by aquatic mammals)
      - Protection
        
        Fat is commonly stored around vital organs to act as a shock absorber and shield layer
  - - - The molecule has the exact same structure as a triglyceride, except for the addition of a phosphate group head
      - phosphate head
        
        This molecule consists of a phosphate molecule, which is bonded to 2 oxygen and two -OH molecules
        
        The phosphate group is hydrophilic meaning it is water loving
- - - - There is very little kinetic energy so there is a decrease in molecule movement
      - The membrane decreases in fluidity so permeability reduces
    - - Increase in kinetic energy leads to an increase in molecule movement
        
        The phospholipids drift (which can be regulated by cholesterol)
      - Embedded proteins reach their optimum temperature and membrane becomes more fluid
    - - An increase in kinetic energy results in an increase in movement of the molecules
      - embedded proteins drift or begin to denature
        
        This results in pores in the membrane
      - The membrane becomes more fluid so permeability increases
    - - The phospholipid bilayer begins to melt and the permeability increases massively
      - The water inside the cell expands which puts pressure on the membrane
      - Channel and carrier proteins deform and denature resulting in the permeability increasing