Chp 5—Lipids & Biological Membranes Flashcards
6 biochemical functions of lipids
- structure of plasma membrane
- energy storage
- protection
- cell signalling
- cofactors
- flavor & fragrance
monomer of lipids
fatty acids
2 components of FAs
carboxylic acid
hydrocarbon chain
2 types of FAs
saturared & unsaturated
delta nomenclature
M:N(𝚫^a,b….)
M = number of carbons
N = number of double bonds
a, b…. = position of double bonds
M:N(𝚫^a,b….)
for delta nomenclature, we number from…
the COOH
components of a triglyceride
3 FAs
glycerol backbone
how are FAs joined to glycerol?
esterification rxn
glycerol
function of triglycerides
energy storage in adipose
simple triaglycerol
3 chains are identical
complex triaglycerol
3 side chains are different
components of wax
joined by?
FA
long alcohol chain
esterification rxn
wax
function of wax
protection and moisture retention
mp of waxes
60-100 C
components of soap
joined by?
triglyceride
aqueous alkali (NaOH, KOH)
saponification rxn
micelle
aggregation of soap molecules around dirt
function of eicosanoids
autocrine & short-range signalling molecules
eicosanoid
eicosanoid SM
arachidonic acid
basic eicosanoid structure
5-mem ring with two acid tails, and many possible R groups
components of phospholipid
phospho “head”
1 or 2 FA tails
components of glycerophospholipid
2 FA tails + glycerol + phosphate + R group
components of sphingolipid
1 FA tail + sphingosine backbone, including nitrogen + R groups
glycerophospholipid
sphingolipid
function of sphingolipids
cell recognition and signal transduction
glycolipid
sugar residue + sphingolipid
basic unit of terpenes/terpenoids
isoprene
function of terpenes/terpenoids
fragrance, flavor, color
function of sterols
component of cell membrane; controls consistency
function of steroids
body-wide signalling hormones
basic structure of sterol/steroid
3 6-mem rings + 1 5-mem ring
lipid vitamins
A D E K
5 components of membrane
glycerophospholipids
sphingolipids
sterols
proteins
carbs
membrane held together by…
hydrophobic interactions
4 main points of fluid mosaic model
- phospholipids have free lateral movement, but not transverse movement
- phospholipids can move 2nm/second
- double bonds in phospholipid tails increase fluidity because they decrease steric space
- majority of mass is from mosaic of proteins
2 main types of proteins in membrane
transmembrane/integral proteins
peripheral proteins
3 common types of transmembrane proteins
alpha helices
helical bundles
beta barrels
peripheral proteins may be ____proteins
lipoproteins
lipid raft
stable domain of proteins which must be in proximity to work together, floating as a unit in the membrane
how is a lipid raft held together
sterols in the membrane make tighter associations between unsaturated tails
2 aspects of membrane function
selective barrier
communication within and among cells
4 steps of primary messenger pathway
- bind to surface receptor
- conformational change of receptor
- dimerization/oligomerization event (might be phosphorylation)
- biochemical pathway activated
3 steps of secondary messenger pathway
- amplification—concentration increases following primary messenger
- bind to internal cellular target
- biochemical pathways are regulated
which second messengers are NOT lipid-derived?
cAMP
Ca2+
IP3 (sugar part of a former lipid)