Human Phys 1.1 Flashcards
What is the common structure of all cell membranes?
They are composed as phospholipids
What type of structures are cell membranes?
Dynamic and fluid structures
What can membrane constituents do?
Move about the plane of the membrane
What percentage of proteins encoded in an animal cells genome are membrane proteins?
30%
What is the most predominant type of phospholipids?
Phosphoglycerides
What do phosphoglycerides contain?
Glycerol backbone
2 hydrocarbon tails
Phosphate group attached to glycerol backbone
What is the tail on a phosphoglyceride?
Hydrophobic
What is the head on a phosphoglyceride?
Hydrophilic
Where does the cis double bond (kink) occur?
In one of the hydrocarbon tails
What does the cis double bond (kink) cause?
Width of lipid bilayer to be shorter
More space between lipid bilayer
What does the cis double bond (kink) increase?
Increases membrane fluidity (important for proper physiological function)
What can phospholipids do?
Spontaneously form bilayers (do it on their own with no help)
What do phospholipid bilayers do because of their amphiphilic nature?
Bury their hydrophobic tails in the interior and expose their hydrophilic heads to water
What does a cone shaped lipid molecule form?
Micelle
What does a cylinder shape lipid molecule form?
Lipid bilayer