Exam 3 Flashcards
functions of a membrane
-phospholipid bilayer
-proteins can be added
-encapsulates cell
-selective permeability
-mobility
-protective barrier
phospholipid bilayer
spontaneous arrangement to protect the hydrophobic tails of a phospholipid
selective permeability
stops/allows certain materials from entering and exiting the cell
phospholipid bilayer is about how thick
50 atoms
phospholipid bilayer is described as
amphiprotic
properties of a phospholipid bilayer
-amphiprotic
-self-sealing
-2 dimensional fluid
-phospholipids can spin on their heads
why is a self sealing bilayer good?
it is energetically favorable, ensures that what is supposed to be in the cell stays in the cell
why is being a 2 dimensional fluid layer good?
allows for lateral movement (diffusion)
why is membrane fushion seamless
bc of phospholipid movement
why is membrane fusion important
it allows for an even number of phospholipids to be divided for diffusion
prokaryotes can do what to their membranes
can change between saturated and unsaturated
the length of a phospholipid tail determines
fluidity
eukaryotes cannot
change between saturated and unsaturated
phospholipid bilayers are (symmetrical or asymetrical)
asymmetrical, bc there is a difference between the cytosolic and extracellular sides
the extracellular layer of a phospholipid bilayer will have
sugars, making it sticky and helps with cell adhesion
