Lipids Flashcards
what is the function of lipids?
storing energy (long-term energy storage, more energy/grams vs carbs)
building cell membrane (phospholipids and cholesterol)
chemical signalling molecules
cushioning organs and insulation
what are the categories of lipids
fats, phospholipids, waxes, steroids
what is the difference between one fatty acid and another?
the length of the carbon chain, and the type of bond
what are the properties of a saturated fatty acid?
carbons with single bonds to hydrogen
linear, because of this they can stack together closely and be solid at room temperature
what are the properties of an unsaturated fatty acid
this includes at least one double bond
(if it only has one double bond this would be a monounsaturated fatty acid)
bent, because if this they cannot stack on top of each other nicely and closely together, therefore they would be liquid at room temperature
what does polyunsaturated mean
this means there are many C=C’s, therefore there would be lots of kinks
why are glycerols created?
since carbon chains are too long, they connect in threes to glycerol, this is overall called a triglyceride
how is body fat created?
carbohydrates are converted into fat which is then stored as droplets in the adipose tissue
what is a condensation reaction?
a reaction that results in a covalent bond between two interacting subunits taking away the hydrogen atoms, more specifically one H from a subunit and an H from an OH of another subunit
the bond created is called an ester bond and this process is called an esterification
what is the structure of fatty acids?
contains a carboxyl group at on end attached to a carbon chain (usually 16 to 18 C long)
saturated vs unsaturated vs polyunsaturated
saturated, think the maximum number of hydrogen atoms
unsaturated, think less than the maximum number of hydrogen atoms
polyunsaturated, think many carbon double bonds
how would you describe the formation of fat?
there is always glycerol as a base, and it’s attached to either one, two, three fatty acids which help create their names, monoglyceride, diglycerides, triglyceride
why are carbon chains put into a condensed form?
the condensed form makes it easier to observe
carboxyl vs carbonyl
carbonyl group consist of a carbon double bonded to oxygen whereas a carboxyl group consist of carbons double bonded to oxygen along with a hydroxyl group (hence why its name ends in “xyl”)
what is the structure of phospholipids?
glycerol connected to two fatty acids similar to diglycerides but it has a highly polar phosphate group
in phospholipids what is the difference between the fatty acids and the phosphate group?
the difference is that fatty acids have a hydrophobic head whereas a phosphate group has a hydrophophillic head
what does amphipathic mean?
a structure containing hydrophilic and hydrophobic parts
what does the amphipathic nature of phospholipids allow phospholipids to do?
allows it to form a variety of cellular structures. theses structures can be manipulated for biotechnological purposes or medical purposes
what is a bilayer?
this is a film two molecules thick. its head is hydrophilic and its inner body is hydrophobic
liposome vs micelle
for liposome, its outer surface is composed of a lipid bilayer, and the layer next to that on the interior is called an aqueous internal compartment, with the middle known as the core of the aqueous compartment. micelle outer surface consists of a closed lipid monolayer with a fatty interior and polar outsides of the structure could be the inverse, a polar core and fatty exterior
what do steroids function as in the body?
they function as hormones throughout various locations of the body
also in the structure of some memebranes
what is the structure of a steroid?
17 carbons atoms arranged in four rings attached to several functional groups
what are waxes and how are they structured?
they are the final category of lipids and they are complex molecules containing long-chain fatty acids connected to alcohol or carbon ring. they are hydrophobic and have a firm consistency, this makes them useful for the outer coating of plants
