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