lecture 12 Flashcards
(21 cards)
What are key components of biological membranes that make them versatile?
boundary that defines cells and organelles
use and store energy
must be flexible and allow for self sealing
adaptable
Whats a glycerophospholipid?
building block of biological membrane with polar head and fatty acid chain
Whats a fatty acid?
carboxylic acid with long hydrocarbon chains
linear
can have 0-6 double bonds
always have even number of carbon
Whats the omega carbon?
The final carbon in a fatty acid chain?
Whats the omega carbon?
The final carbon in a fatty acid chain?
What trends pertain to the mp of fatty acids?
As C-H bonds in the tail increase, so do the induced dipoles and the melting temperature
6-10C by each
How do cis fatty acids affect melting point?
Decrease melting point by a lot bc difficult to pack tightly
How do trans fatty acids affect melting point?
decrease mt by a bit but not as much as cis bc no 30C kink
what’s a triacylglycerol?
glycerol headgroup with 3 fatty acid chains
hydrophobic and stored in lipid droplets in adipocytes
What are the characteristics of lipids in the membrane?
soluble in non polar organic solvents
usually insoluble in H2O
What are the three classes of membrane lipids?
glycerophospholipids/phosphoglycerides
sphingolipids
sterols
What happens to mt at room temp depending on membrane composition?
more saturated fatty acids: more solid fat at RT, increase mp
more unsaturated: more liquid at room temp, decrease mp
What is the structure of a glycerophospholipid?
polar head group, phosphate, glycerol, and fatty acid chains
what is a phosphoserine?
a head group common in glycerophospholipids that has a phosphate
What is a cardiolipin?
a diphosphoglyceride that compromises the inner mitochondrial membrane
it is an insulator and stabilizer of protein complexes
Whats a sphingolipid?
serine+palmitate tale to to make ceramics chains
What are the classes of sphingolipids?
sphingomyelins: found in myelin sheath and attach a phosphate containing head group
cerebroside: headgroup is a singular sugar like glucose or galactose
ganglioside: complex oligosaccharide head group with one silica acid
What is a GM! ganglioside?
found in ganglion cells,
complex carb headgroup on outside of plasma membrane that binds specific protein and causes signal transduction for pituitary hormone and cholera
can lead to tay sachs
What are the cholesterol membrane lipids?
What does cholesterol do to a membrane?
decreases membrane fluidity
What is a cholesterol
4 fused non polar rings, 3 6 member and. 5 member
