Lipids and Membranes NOT COMPLETE Flashcards
chain length for naturally occuring fatty acids
12-24 carbons
why are fatty acid hydrocarbon chains usually even?
synthesis involves successive condensation of two-carbon acetyl units
how is the position of C=C bonds given in fatty acid nomenclature
superscribe delta, number is the lower numbered carbon involved in double bond
which bond links fatty acid chains to the glycerol backbone?
ester linkage
note: esterification also important for formationof carbohydrates and proteins
what kind of reaction is the esterification reaction?
condensation
why are triglycerides neutral lipids?
polar hydroxyl groups of glycerol bonded to polar carboxylate groups on fatty acids
resulting molecule is nonpolar
three types of membrane lipids
phospholipids
glycoplipds
cholesterol
which property of membrane lipids describes their hydrophilic and hydrophobic properties
amphiphatic
hydrophilic regions on membrane lipids
phospholipids - phosphate with bound alcohol
glycolipids - phosphate with bound sugar
cholesterol - OH group
hydrophobic regions on membrane lipids
phospholipids and glycolipids - fatty acid tails
cholesterol - sterol nucleus (fused hydrocarbon rings) and hydrocarbon tail
structure of phosphoglyceride
glycerol backbone
two fatty acid tails joined via ester linkage
phosphate group joined via phosphodiester bon
alcohol joined to phosphate
different phosphoglycerides have different alcohols attached
structure of glycolipid
glycerol backbone
two fatty acid tails joined via ester linkage
phosphate group joined via phosphodiester bon
sugar joined to phosphate
structure of cholesterol
steroid nucleus - four fused carbon rings (three six membered, one five membered)
OH group
hydrocarbon tail
structure of biological membranes
phospholipid bilayer with inner and outer leafletmembrane lipid and protein content of leaflet differ - asymmetric
structure held by non-covalent interactions (including hydrophobic interactions)
rapid lateral diffusion of membrane lipids and proteins
