Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
96 Cards in this Set
- Front
- Back
name the six roles of lipids
|
cofactors, pigments, signaling molecules, hydrophobic anchors for proteins, chaperones, emulsifing agents in the digestive tract
|
|
T or F fatty acids are conjugated
|
false
|
|
where do double bond occur in monounstaturated and polyunsaturatedd fatty acids
|
mono=9-10
ploly=12-15 |
|
name three chemistry facts about fatty acids
|
even number of carbons
usually linear low oxidation state |
|
what influences melting points of fatty acids
|
chain length and degree of unsaturation
CL=longer chains means higher meltingT DOU= less double bonds mean higher melting temp |
|
What is the solubilty of Fatty acids
|
low water solubility
high organic solvent solubilty (benzene) longer the chain length means lower solublity |
|
Saturated and unsaturated fatty acids of C12-C24 are characterized by what at room temp
|
saturated=waxy
unstaturated=oily |
|
how are most fatty acids found in blood plasma
|
as an ester or amide derivative that are less soluble then a FFA
|
|
what is the common name of a 16 carbon saturated fatty acid
|
palmitic acid
|
|
what is the common name of a 18 carbon saturated fatty acid
|
stearic acid
|
|
what is the common name of an 18 carbon unsaturated fatty acid
|
oleic acid
|
|
what is the common name of a 18 carbon polyunsaturated fatty acid (9,12)
|
linoleic acid
|
|
what is the common name of a 18 carbon polyunsaturated fatty acid (9,12,15)
|
alpha linoleic acid
|
|
what is the common name of a 20 carbon polyunsaturated fatty acid
|
arachidonic acid
|
|
what types of fatty acids are found in membranes typically sat/unsat
|
both
|
|
what is the major storage lipid
|
triaclyglycerol
|
|
what is a triacylglycerol
|
three fatty acids joined to a glycerol backbone
|
|
what is the simplest lipid made from fatty acids
|
triacylglycerol
|
|
what is an example of mixed and simple fatty acids
|
mixed=2 or more diff FA
simple=all the same kind of FA |
|
what type of linkage is used in triacylglycerols
|
ester linkages
|
|
what are 3 unique properties of triacylglycerols
|
1. less polar then substituents
2. lower density than water (float) 3. separate as droplets in cells ( E depot) |
|
why are fats not easily retreivable
|
insoluble in water
|
|
what is the main way to separate lipids
|
organic solvent extractions
|
|
what is a good way to analyse the structure of a fatty acid
|
mass spectroscopy
|
|
what are the two components of a biological wax and how are they joined
|
fatty acid chain is joined to a long chain alcohol through ester bonds
|
|
how do waxes and triacylglycerides differ in melting temp
|
waxes are higher about 60-100 higher
|
|
what are waxes used for in nature
|
metabolic fuel (plankton)
water proofing |
|
what are waxes used for in the real world
|
lotions, ointments, polishes and dental molds
|
|
what are the six types of structural lipids in membranes
|
phospholipids
glycolipids choleterol ether lipids chloroplast membrane lipids archaebacterial ...... lipids |
|
what is a plasmalogen
(platlet activating factor) |
similiar to a phospholipid but contains an ether linkage
these are resistant to damage from oxygen free radicals |
|
what are two types of phospholipids
|
glycerolphospholipid
sphengomyelin |
|
in a glycerolphospholipid what is the usual number of carbons of the two fatty acid chains at c1 and c2
|
c1=16-18 (saturated)
c2=18-20 (unsaturated) |
|
what is unique about C2 in glycerolphospholipids
|
it is chiral
|
|
what is a lysophospholipid
|
a glycerolphospholipid missing one fatty acid chain
|
|
what is a diacylglycerol
|
glycerolphospholipid missing the phosphate containing head group
|
|
what is an ether lipid
|
same as a glycerolphospholipid but one of the FA chains is joined be an ether rather than an ester
|
|
what are the names and net charges of the six typical head groups that we studied
|
1. Ethanolamine 0
2. choline 0 3. serine -1 4. glycerol -1 5. inosital 4,5 bisphosphate -4 6. phophotidylglycerol -2 |
|
what is sphingosine
|
a long chain amino alcohol used in the backbone of sphingolipids
|
|
what is cereaminde
|
similiar to diacylglycerol
a sphengolipid missing the phosphate containing head group |
|
what is a sphengomyelin
|
a sphengolipid with a choline as the head group
|
|
what is a ganglioside
|
a sphengolipid with a complex oligosaccaride containing a negetively charged sialic acid
|
|
how are glycolipids and sphingolipids related
|
glycolipids are shingolipids with sugars as the head groups
|
|
what is a cerebroside
|
a glycolipid with only 1 sugar as the head group
|
|
what is a globoside
|
a glycolipid containing a multistranded sugar chain as the head group
|
|
what are the diseases resulting from impaired membrane sphengolipid degradation
|
Tay-Sacs
Sandhoff's Fabry's Goucher's Niemann-Pick |
|
as lipids go from the individual state to clusters to micelles what is the result in entropy terms
|
increases as the lipids become more ordered
|
|
what is a liposome used for
|
for drug delivery
|
|
what are the three non-covalent forces that hold lipid bilayers together
|
van der waals between side chains
electrostatic between polar heads hydrogen binding between polar heads |
|
what are three structural characteristics of a lipid bilayer
|
flexible
self-sealing impermeable to charged molecules |
|
what is another name for transverse diffusion
|
flip flop
|
|
what is the enzyme that catalyses transverse diffusion
|
flippase
|
|
what is the enzyme that flips phospolipids to the outside of the membrane to signal apoptosis
|
scramblase
|
|
what types of fatty acid chains favor the paracrystalline state for the lipid bilayer
|
long saturated fatty acid chains
|
|
what types of fatty acid chains favor the fluid state for the lipid bilayer
|
short unsaturated fatty acid chains
|
|
In the lipid bilayer what are the effects of short unsaturated fatty acid chains on viscosity and transition temp
|
they decrease viscosity and decrease transition temp
|
|
T or F cholestrol is amphipathic
|
T
|
|
T or F the nucleus of cholesterol is planar and flexable
|
F planar and rigid
|
|
T or F the alkyl group at C17 of cholesterol is rigid
|
F it is flexable
|
|
where is cholesterol inserted in the lipid bilayer
|
between glycolipids and phosopholipids
|
|
what is the result of having a cholesterol inserted into a lipid bilayer
|
decreases transitional temp increases viscosity and fattens the membrane
|
|
what phospolipid does scramblase act on
|
phosphotidylserine
|
|
what are the three main phospholipids on the outer monolayer of the lipid bilayer
|
phosphotidylethanolamide
phosphotidylcholine sphingomyelin ( glycolipids ) |
|
what serves as a precursor for membrane synthesis with sphingolipid derivitives
|
ceramide
|
|
Why are sphingolipids more concentrated on the outer monolayer
|
the mode of synthesis, the head groups are attached to ceramide in the lumen of the golgi. inside of the golgi ends up on the outer surface
|
|
what defines a plasmologen
|
an ether lined alkene at C1 and a choline at C3
|
|
what are the physiological responses that platelet-activating factor elicits
|
platlet aggregation
inflamation allergic responses |
|
what defines a platlet activating factor
|
similar to plasmologen
C1=ether linked alkane C2=acetyl ester (very water soluble) C3=choline |
|
What is unusual about archeabacteria membranes
|
the lipids involved span the width of the whole membrane and contain ether linkages at both ends that are resistant to hydrolyses at low Ph and high temp
|
|
what is a another scientific name for blood group antigens
|
ceramide based glycolipids
|
|
what are the pathogenic responses the lipopolysaccarides is involved with
|
TSS, sepsis, ARDS, multiple organ failure syndrome
|
|
where are lipopolysaccarides located
|
the outer membrane of gram negative bacteria, good targets for antibodies
|
|
what is about the average protein content for a lipid bilayer
|
about 50%
|
|
what are the agents that can remove a peripheral protein from the membrane
|
high salt
change in Ph chelating agent urea CO32- |
|
what are the agents that can remove a integral protein from the membrane
|
detergent
same as bile salts |
|
how are integral proteins and peripheral proteins connected
|
protein to protein non-covalent interacitions
|
|
How is the oreintation of an integral protien determined
|
by the primary sequence of the amino acid
|
|
what is the purpose of having multiple helices of protein in the plane of the membrane
|
they can have fuctions such as enzymes, transport, or signaling
|
|
what is bacteriorhodopsin
|
7 pass transmembrane protein, typical of the G protein family
|
|
what does a hydropathy plot predict
|
the transmembrane alpha-helical domains (wether or not phobic or philic)
not affective with Beta barrel structures |
|
how many amino acid are required to span the hydrophobic interior of a lipid bilayer
|
about 20
around 23 if cholesterol is involved |
|
what is the function of a Beta barrel
|
they are transmembrane domains
|
|
what is a beta barrel
|
20 or more transmembrane segments form beta sheet to line a cylinder this complex is the beta barrel
|
|
what type of bond anchors protiens to lipids
|
covalent
|
|
when an internal cysteine or ser group of a protien is added to a palmitoyl group is it done posttranslationally or cotranlationally
|
postransitlationally
|
|
when an amino terminal glycine group of a protien is added to a N-Myristoyl group is it done posttranslationally or cotranlationally
|
cotranslationally
|
|
why is carboxyterminal binding of cysteine to farnesyl important in cancer research
|
this complex is important in GTP binding
|
|
In N-linked oligosaccarides what is the molecule that the oligosaccarides are formed on before being added Asn
|
dolichol
|
|
In N-linked Oligo's after the sugars are added to the Asn what is added and what is removed and where does this take place
|
mannose is removed and new sugars and sialic acid is put on. done in the golgi
|
|
how are O-linked oligo's formed and where
|
stepwise directly added to Ser/Thr. all done in the golgi
|
|
what is the main glycoprotein in RBC's
|
glycophorin
|
|
what is a glycophorin
|
single pass transmembrane glygoprotein for RBC's
|
|
where does conventional glycosylation occur
|
the plasma membrane, secretory, lysosomal proteins
|
|
where does complex carbohydrate N and O linked take place
|
N=ER then modified in the golgi
O=Golgi these both end up on the outside of the membrane they join. |
|
what is a proteoglycan
|
a GAG chain attached to Ser of a Gly-X-Gly sequence of core protein by a trisaccharide bridge.
|
|
what is the main site of biological activity in a proteoglycan
|
the GAG chain
this is also the major bulk of the proteoglycan |
|
what is the main component of cartilage and connective tissue
|
proteoglycan
|