Chap 3 class notes
BILayer structure
[HIGH YIELD]
the bilayer or plasma membrane is intergral to a cell
it's primary functions ; to control what enters / exists the cell + acts as a
barrier between external and internal cellular environemts
primarily consists of ;
phosphilipids that make up the phospholipid bilayer → these consits of
glycerol phosphate heads which are hydrophilic and hence polar, pointing
towards polar mediums → 3 fatty acid tails that are non-polar and hence
hydrophobic. CHO elements present here
cholesterol molecules → regulate fluidity of membrane to uphold fluid
mosaic model → at low temps ; cholesterol molecules act as glue to ensure
that phopholipids do not part, at high temps, act as spacers to esnure that
fatty tails do not join → are present between tails of adjacent phospholipids
carbohydrate chains + glycoproteins → involved in cell-cell communication
channel proteins → typically have a hydprohilic interior and a hydrophobic
exterior to exist between fatty acid tails. Allow for transprotation thru active
or facilitated diffusion of polar/large molecules
Passive transport
Diffusion
[HIGH YIELD]
the passive movmenet of small, hydrophobic molecules through a semi-
permeable membrane with the natrual concentration gradient, from regions
of high concentration to low concentrations.
this occurs passively and hence does NOT require energy ( ATP )
Chap 3 class notes 1
BILayer structure
[HIGH YIELD]
the bilayer or plasma membrane is intergral to a cell
it's primary functions ; to control what enters / exists the cell + acts as a
barrier between external and internal cellular environemts
primarily consists of ;
phosphilipids that make up the phospholipid bilayer → these consits of
glycerol phosphate heads which are hydrophilic and hence polar, pointing
towards polar mediums → 3 fatty acid tails that are non-polar and hence
hydrophobic. CHO elements present here
cholesterol molecules → regulate fluidity of membrane to uphold fluid
mosaic model → at low temps ; cholesterol molecules act as glue to ensure
that phopholipids do not part, at high temps, act as spacers to esnure that
fatty tails do not join → are present between tails of adjacent phospholipids
carbohydrate chains + glycoproteins → involved in cell-cell communication
channel proteins → typically have a hydprohilic interior and a hydrophobic
exterior to exist between fatty acid tails. Allow for transprotation thru active
or facilitated diffusion of polar/large molecules
Passive transport
Diffusion
[HIGH YIELD]
the passive movmenet of small, hydrophobic molecules through a semi-
permeable membrane with the natrual concentration gradient, from regions
of high concentration to low concentrations.
this occurs passively and hence does NOT require energy ( ATP )
Chap 3 class notes 1
