Ch 5: Lipid Structure and Function Flashcards
lipids are soluble in
nonpolar organic solvents
the head group of phospholipids are attached by a ____ and bc it interacts with the environment, determines the function of the phospholipid
phosphodiester linkage
saturated fatty acids are ____ fluid than unsaturated
less
phospholipids that contain a glycerol backbone
glycerophospholipids
_____ contain a sphingosine backbone; many but not all are also phospholipids with a phosphodiester bond; these are called ____
Sphingolipids
Sphingophospholipids
Sphingomyelins
are the major class of sphingophospholipids and contain a phosphatidylcholine or phosphatidylethanolamine head group. they are the major contributer in the myelin sheath
_____ attached to sugar moieties instead of a phosphate group. ____ have one sugar connected to sphingosine; ____ have two or more
glycosphingolipids
cerebrosides
globosides
gangliosides
contain oligosaccharides with at least one terminal N-acetylneuraminic acid (NANA; also called sialic acid)
waxes contain long-chain fatty acids that are ___ to long chain alcohols
esterfied
terpenes
odiferous steroid precursors from isoprene, a five carbon molecule
one terpene unit (a monoterpene) contains
2 isoprene units
terpenoids are derived from terpenes via
oxygenation or backbone rearrangement. they have similar odorous characteristics
Steroids
contain three cyclohexane rings and one cylcopentane ring
oxidation state and functional group may vary
steroid hormones have
high-affinity receptors, work at low concentrations and affect gene expression and metabolism
cholesterol is a
steroid hormone important to membrane fluidity and stability; it serves as a precursor to a host of other molecules
____ are autocrine and paracrine hormones that regulate cAMP levels. they have powerful effects on muscle contraction, body temp, the sleep-wake cycle, and pain
Postaglandins
fat-soluble vitamins include
A,K,E,D
Vit A (carotene) is
metabolized to retinal for vision and retinoic acid for gene expression in epithelial development
carotene - carrots are high in vit A eat to improve vision
Vit D (cholecalciferol) is metabolized to
calcitriol in the kidneys and regulates calcium and phosphorus homeostasis in the intestines (inc ca and phosphate absorption), promoting bone formation. deficiency of this causes rickets
D regulates calcium, remember it is freq added to milk to aid in absorption of calcium
Vit E (tocopherols)
act as biological antioxidants. their aromatic rings destroy free radicals, preventing oxidative damage
Vit K (phylloquinone and menaquinones)
important for formation of prothrombin, a clotting factor. performs posttranslational modifications on a number of proteins, creating calcium binding sites
vit k is for koagulation
preferred method of storing energy for long-term use
they contain one glycerol attached to 3 fatty acids by ester bonds
very hydrophobic so not hydrated by water in body and therefore do not carry extra weight
triacylglycerols (triglycerides)
carbon atoms in ____ are more reduced than ___ , giving twice as much energy per gram during oxidation
lipids
carbohydrates
animal cells specifically used for storage of large triacylglycerol deposits are called
adipocytes
free fatty acids are
unesterfied fatty acids that travel through the bloodstream
salts of free fatty acids are ____ and can be synthesized in saponification
soaps
saponification
is the ester hydrolysis of triacylglycerols using a strong base, like Na or KOH
Micelles can dissolve a ___ in its fatty acid core, and washes away with water bc of its shell of ___ head groups
lipid-soluble molecule
carboxylate
