lecture 8 Flashcards
what is the one defining characteristic of lipids
lipids are insoluble in water but soluble in nonpolar solvents
do lipids form polymeric molecules, what do they form instead
no, but some fatty acids do combine with other molecules to create larger macromolecules or cellular structures
what do many lipids serve as
fuel and building materials
what can fatty acids be used as by some cells
as an energy molecule (energy source) to generate ATP
what are fatty acids building blocks for
larger lipids like fats (triacylglycerides) and phospholipids
fats are what type of moleclue
energy storage molecule (triacyglycerides)
examples of a steroid
cholesterol and phospholipids
what are other types of lipids
pigments (chlorophyll) and waxes (ear wax)
what type of molecule is fatty acids
amphipathic molecules
describe the structure of a fatty acid
hydrophilic carboxylic head and long hydrophobic hydrocarbon tail
what type of molecules of fatty acids form in aqueous environments
films and micelles to allow heads to interact with water and tails to avoid water
what are types of variations in fatty acid tail structure
-lengths of fatty acids vary
-some fatty acids will have one or more double carbon bonds in their structure
-saturated vs unsaturateds
saturated fatty acids
fatty acids with no double bonds
unsaturated fatty acids
have one or more double bonds in hydrocarbon tail
desrcibr the structure of a unsaturated fatty acid
double bond is rigid and causes a kink so it does not hang straight down
monosaturated fatty acid
has one double carbon bond
polyunstaurated fatty acid
has ore than one double carbon bond
saturation impacts ability of fatty acids to do what
to pack and remain close together
what do lors of saturated fatty acid tails stacked together lead to
van der waals interactions
-on less packed fatty acids there are fewer van der waals
What about the fatty acid impacts the behavior of larger molecules that contain fatty acids
saturation
what are fat molecules also known as
triacylglycerides or oils
describe fatty acids in animal
long staright saturated fatty acid moelcule because fat in animals is more solid (like butter)
describe fatty acids in plants
unsaturated because fat in plants is lipid (like oils)i
is more energy needed to dissociate saturated or unsaturated fats
saturated
–animals store excess energy as fat, while plants convert excess glucose into starch
phospholipid is
another type of amphipathic molecule
describe the structure of phospholipid
each phospholipid has two fatty acid tails
-they assemble into bilayers in an aqueous environment
cholin
polar either charged or uncharged
glycerol
attaches to 2 fatty acids and phosphate group
what do phospholipids do in an aqueous environment
form bilayers that vesicles (creates an effective barrier)
steroids are
another class or lipid molecule
what type of surface does chlolestpral have and structure
hydrophobic surface
-has one hydrophilic hydroxyl group
what are the two types of steroid hormones
-estradiol
-testosterone
does saturated or unsaturated have higher melting temps
saturated because it has more van der waals forces holding them together because they are easier to pack together without the double carbon bonds
