Lipid Structure and Function Flashcards
Structural lipids characteristics
Lipids are insoluble in water and soluble in
nonpolar organic solvents.
Phospholipids
- structure
- bonds
Amphipathic and form the bilayer of membranes.
Contain a hydrophilic (polar) head and hydrophobic
(nonpolar) tails. The head is attached by a
phosphodiester linkage, and determines the
function of the phospholipid
Saturation
Saturation of the fatty acid tails determines the
fluidity of the membrane. Saturated fatty acid =
less fluid.
Single bonds means it is saturated
Glycerophospholipids structure
Phospholipids that contain a glycerol backbone
Sphingolipids structure and bonds
Contain a sphingosine backbone. Many (but not all)
sphingolipid are also phospholipids with a
phosphodiester bond. These are
sphingophospholipids.
Sphingomyelins:
The major class of sphingophospholipids and
contain a phosphatidylcholine or
phohsphatidylethanolamine head group. Part of
the myelin sheath.
Sphingomyelins
The major class of sphingophospholipids and
contain a phosphatidylcholine or
phohsphatidylethanolamine head group. Part of
the myelin sheath
Glycosphingolipids
Attached to sugar moieties instead of a phosphate
group
Glycosphingolipids - Cerebrosides
have 1 sugar connected to
sphingosine
Glycosphingolipids Globosides
Have 2 or more sugars connected to sphingosine
Gangliosides
Contain oligosaccharides with at least 1 terminal Nacetylneuraminic
acid (NANA).
Waxes
Contain long-chain fatty acids esterified to longchain
alcohols. Used as protection against
evaporation and parasites in plants and animals.
Terpenes
Odiferous steroid precursors made from isoprene. One terpene unit (monoterpene) contains 2 isoprene units
Terpenoids
Derived from terpenes via oxygenation or backbone
rearrangement. Odorous characteristics.
Steroids
Contain 3 cyclohexane rings and 1 cyclopentane
Steroid Hormones
Have high-affinity receptors, work at low
concentrations, and affect gene expression and
metabolism.
Cholesterol
A steroid important to membrane fluidity and stability;
and serves as a precursor to many other molecules
Prostaglandins:
Are autocrine and paracrine signaling molecules that
regulate cAMP levels. Affect smooth muscle
contraction, body temp, sleep-wake cycle, fever, pain
Vitamin A:
Carotene, vision
Vitamin D:
Cholecalciferol, bone formation.
Vitamin E:
Tocopherols, antioxidants
Vitamin K:
Phylloquinone & menaquinones. Forms
prothrombin, a clotting factor.
Triacylglycerols:
Storage form of fatty acids. Contain 1 glycerol attached to
3 fatty acids by ester bonds. Very hydrophobic so do not
carry additional water weight.
Adipocytes
Animal cells used specifically for storage of large
triacylglycerol deposits
Free Fatty Acids
Unesterified fatty acids that travel in the bloodstream.
Salts of free fatty acids are soaps
Saponification
The ester hydrolysis of triacylglycerols using a strong base
like sodium or KOH.
Micelle
Can dissolve a lipid-soluble molecule in its fatty acid core,
and washes away with water because of its shell of
carboxylate head groups
