Lecture 1 Membrane Structure Flashcards
What are the properties/functions of mammalian plasma membrane?
Maintain separation of environments
Regulate Import/Export of Molecules across membrane
Provide Supportive support(STRUCTURE)
Help w/ Cell movement via expanding and contracting
LO: What are the properties/functions of mammalian plasma membrane?
Maintain separation of environments
Regulate Import/Export of Molecules across membrane
Provide Supportive support(STRUCTURE)
Help w/ Cell movement via expanding and contracting
LO: What properties of phospholipids allow for spontaneous membrane formation and how do they do it?
Phospholipids form in the SER in a cytosolic monolayer and moved to form a bilayer via scramblase
LO: How do plasma membrane formation with flipase and floppase
FLIPPASE: moves to cytosolic side
FLOPPASE: moves to EC/Luminal side
both help to form a bilayer. they are specific and will work immediately. Need Energy to occur.
LO: Describe the structure and function of phospholipids.
(Which is charged, what is this ones functional significance, is it preferential on cytosolic or EC, what is the functional significance of plasma asymmetry
Phosphatidylserine is negatively charges, it prefers to be on Cytosolic side
If it were to switch then flippase comes in and moves back to cytosol side however in cell death flippase becomes inactive and when scramblase moves to EC side then apoptosis occurs
LO: Describe the structure/function of cholesterol and how it maintains optimal fluidity
Cholesterol helps fluidity by providing rigidness w/ its ring
conversely membrane that is too rigid can become more fluid w/ kinks/double bonds and length
LO: Describe the basic structures/Function of glycolipids
Sugars are added via glycosylation in the ER and can interact with lipid rafts.
LO: How do each Affect Membrane fluidity
-Level of phospholipids tail saturation
-Levels of cholesterol
-Phospoliids tail lenght
-Tail saturation(Single bonds) when more single bonds more rigid, and double bonds increase fluidity
-Cholesterol can provide optimal fluidity, Can increase or decrease
-Tail length the longer the more rigid.
LO: what would occur id plasma membrane was unable to maintain optimal fluidity
then the membrane can start to breakdown but the cell can modify phospholipids/cholesterol production/delivery to combat this
LO: Describe the structure/function of lipid rafts
LO: Understand the 8 structure types of protiens
LO: Compare/COntrast the degree to which protiens are attached to membranes. Which have Lateral movement an
Lo: Where glycosylated lipids and protein s are found
cell to cell adhesions
this is because they are formed in the Golgi Lumen which when brought to the membrane moves to the EC side
