lipids and cell membrane
the double bond in the unsaturated fatty acids almost always have the ______ conformation? what does this cause in the hydrocarbon chain?
cis, bend
the main biological functions of lipids include ____ as _____ components of cell membranes and as important signaling molecules?
energy storage, structural
in phospholipids the C1 and C2 positions are ____ with fatty acids to form ____?
esterified, glycerophospholipid
in triacylglycerols the double bond results in the less efficient packing of the hydrocarbon chain, thereby decreasing the ____?
melting point
the more lipids that are clustered they will form ____ ordered shell?
micelles
most frequent diffusion method used in lipid mobility in biological membranes
uncatalyzed lateral diffusion
diffusion between lipid monolayers is difficult and very slow (hours to days)
uncatalyzed transverse diffusion
3 basic mechanisms for transport of substances across biological membranes
uniport, symport, antiport
fatty acids are chemically classified as _____, however have the same affect as saturated fatty acids in the body in that they increase the risk of_____
unsaturated fatty acids, heart disease
virtually all animal cells have a Na+/K+ pump, if the intracellular Na+ level was high what would happen to the cell?
water would rush into the cell and burst it
dynamic nature of membranes is known as the ____?
fluid mosaic model
phospholipids are a major component of biological membranes and they consist of _____?
glycerol-3-phosphate
what 2 things can diffuse laterally in a bilayer?
phospholipids, membrane proteins
biological membranes are bilayers of lipids primarily ____ and ____?
phospholipids, sphingolipids
fatty acids do not occur in _____ and only in small amounts in animals. they are formed in the ____ of vegetable oils
plants, hydrogenation
biological membranes form a bilayer so that the ____groups point out toward the aqueous solvent while the ______ point inward away from the solvent
polar heads, hydrocarbon tails
Triacylglycerols (triglycerides) usually contain how many different fatty acids?
2 or 3
because of the hydrophobic interior of lipid bilayers they are not permeable to ions such as ___ and ____?
Na+ and K+
digitals inhibits the activity of the ______ thereby increasing the intracellular levels of ____ which activates the _____ anti porter in the cardiac muscle
Na+/K+ pump, Na+, Na+/Ca+2
_____ fatty acids can compact and interact with one another, its string and increases the melting temp so solid at room temp
saturated
mixture of ____ and _____fatty acids in the cis configuration, you have bends, it disrupts the linear configuration and decreases the melting temp so its liquid at room temp?
saturated and unsaturated
oleic acid is a _____ fatty acid and a __ octadecanoic acid, how many carbons does it have, double bonds?
unsaturated, cis, 18:2
the Tm of a bilayer increases with increasing _____ and degree of _____ for the same reasons the melting point of fats increase with these parameters
chain length, saturation
a broad group of naturally-occurring molecules which includes fats, waxes, sterols, fat-soluble vitamins: monoglycerides, diglycerides, phospholipids, and others
lipids
the double bonds in polyunsaturated fatty acids occur at every _____and thus are not ____?
third, conjugated
the Na+/K+ ATPase is an example of _____?
antiport active transport
the gradient of the Na+/K+ pump is so important that it is responsible for ____ of the total energy expenditure of humans at rest
25%
membrane proteins can be all ____ or consist of solely ____ strands?
alpha-helical, beta strands
phospholipids are _____ in that they have a non polar (hydrophobic) tail and a polar (hydrophilic) head
amphiphilic
3 biological functions of lipids? 1. components of ______ 2. serve as _____ 3. serve as important _____
biological membranes, energy stores, signaling molecules
fatty acids are ______ with a long hydrocarbon chain?
carboxylic acids
diffusion between lipid monolayers that is fast and is catalyzed by flippase
catalyzed Transverse diffusion
cholesterol does what to membrane fluidity and melting temp?
decreases, increases
natural product isolated from the leaves of the foxglove plant, has been used to treat congestive heart failure since the 1700s
digitals
paracrine hormones meaning that they act on cells near where they are synthesized
eicosanoids
to transport ions and molecules across membranes, proteins are _____?
embedded in the membrane
most polar molecules such as ____ and ____ are not permeable to biological membranes with the exception of ____?
glucose and amino acids, water
example of coupling an antiport system to a symport system
glucose transport in the small intestine
the major driving force for formation of lipid bilayers
hydrophobic interactions
the hydrophobic residues interact with the ____ of the lipid bilayer, while the charged and polar amino acids face ____ away from the ____?
hydrophobic tails, inward, hydrophobic membrane interior
membrane bound proteins mediate transport of ?
ions and polar molecules across membranes
used to form biological membranes, which are the barriers that define the inside and outside of a cell?
lipids
oils which are ____ at room temp contain unsaturated fatty acids
liquids
in the Na+/K+ pump 3 Na+ are pumped ____ while 2 K+ are pumped _____. this creates an _____ across the membrane, which is responsible for the electrical excitability of nerve cells
out, in, electrical gradient
eicosanoids are involved in the production of ____ and ____, regulation of blood pressure, blood ____ and _____?
pain, fever, coagulation, reproduction
chloride-bicarbonate exchanger in erythrocytes
passive antiport
glucose transporter of erythrocytes
passive uniport
4 main types of polar head groups? 1. _____ acid 2. phosphatidylethanolamine 3. _____ 4. ____
phosphatidic phosphatidylcholine phosphatidylserine
linoleic acid is a _____ fatty acid and a __ octadecanoic acid, how many carbons does it have, double bonds?
polyunsaturated, cis cis, 18:2
palmitic acid is a ____ fatty acid and is a hexadecanoic acid, how many carbons does it have?
saturated, 16
fats which are ____ at room temp usually contain saturated fatty acids
solid
____ is abundant in the myelin sheath that surrounds some nerve cells in animals. important for the signal to be transported
sphingomyelin
Derivatives of cyclopentanoperhydrophenanthrene which has 4 fused non polar rings A-D
steroids
when unsaturated fatty acids with the cis configuration in the corn oil are hydrogenated to form the _____ this does what to the melting point?
trans conformation, raises it (liquid to solid)
what are the major classes of lipids? 1. fatty acids 2. _______ 3. phospholipids 4. ______ 5. _______ 6. eicosanoids
triacylaglycerols sphingolipids steroids
animal fats consist of _____ which function as an energy reservoir
triacylglycerols