Lipids, Beta Oxidation, lipid syntesis (complete) Flashcards
What are some biological functions of lipids
- STORAGE OF ENERGY
- Insulation
- Water repellant
- Buoyancy
- MEMBRANE STRUCTURE
- cofactors for enzymes
- SIGNALING MOLECULES
- Pigments
- Antioxidants
What makes Lipids effecient at storing energy
- they are reduced compounds (lots of available energy)
2. their hydrophobic nature (Good for tight packing)
What role do lipids play in membrane structure
they are the main structure of cell membranes
What signaling molecules are made of lipids
- paracrine hormones
- steroid hormones
- Growth factors
- Vitamins A + D
What determines if a fatty acid is an Omega 3 (or Omega 6) fatty acid
Omega 3 fatty acids are fatty acids that have a double bond that begins on the third Carbon counting from the back of the fatty acid.
(Omega 6 are fatty acids that have a double bond that begins on the 6th carbon from the back)
Do humans Synthesize omega 3 fatty acids
nope
Do humans need omega 3 fatty acids
yes
is omega 3 an essential nutrient
yes
How is the solubility of a fatty acid affected by its chain length
the longer the chain the less soluble it becomes
how is the melting point of a fatty acid affected by its chain length
the longer the chain the higher the melting point
how is the melting point of a fatty acid affected by the number of double bond it has
the more double bonds a fatty acid has the lower the melting point
Which type of fatty acid will be the least soluble
a long one
which type of fatty acid will have the highest melting point
the longest fatty acid with the least number of double bonds
Which type of fatty acid will have the lowest melting point
a short fatty acid with many double bonds
What is a saturated fatty acid
a fatty acid without double bonds
what is an unsaturated fatty acid
a fatty acid with double bonds
What is a monounsaturated fatty acid
a fatty acid with one double bond
what is a polyunsaturated fatty acid
a fatty acid with multiple double bonds
What are the steps in naming a fatty acid
A:B (DeltaC,C,C) D-C- Name
A = Number of carbons in the fatty acid
B = The Number of double bonds in the fatty acid
C = The different Carbon #’s that start a double bond
D = whether the C double bond is cis or trans
18:1 (Delta 9) cis-9- (NAME)
how many carbons does this fatty acid have
18
18:1 (Delta 9) cis-9- (NAME)
how many double bonds does this fatty acid have
1
18:1 (Delta 9) cis-9- (NAME)
where does the double bond of this fatty acid begin
the 9th carbon
18:1 (Delta 9) cis-9- (NAME)
is the double bond in this fatty acid cis or trans
cis
Which type of bond is more common in natural unsaturated fats
Cis
What does the Cis double bond lead to in the fatty acid chain
a kink in the chain
Which fats pack and stack better: unsaturated or saturated fats
saturated fats
why don’t unsaturated fats pack and stack as well as saturated fats
because their double bond puts a kink in the chain
Which type of fatty acids have a higher melting point: saturated or unsaturated fatty acids
saturated fats
why do saturated fats have a higher melting point than unsaturated fats
because saturated fatty acids are straight and stack better, so the have greater van der waal forces between them, making them harder to pull apart.
What is a trans fatty acid
unsaturated fatty acids that are partially dehydrogenated. this gives it a trans double bond instead of a cis double bond
what does a trans double bond do to the fatty acid
makes it more extended (less kinked) which gives it a higher melting point
why are trans fats made
it increases the shelf life
it has a higher melting point (solid at room temp)
What is the problem with trans fats
consuming them increases the risk of cardiovascular disease
What does the basis of lipid classification come from
the structure and function of the lipid
Do all lipids contain fatty acids
nope
What is an example of lipids that don’t have fatty acids
cholesterol
What are the two different classifications of lipids that DO have fatty acids
storage lipids and membrane lipids
What is the name for the type of lipids that are storage lipids
triacylglycerols
What are the different categories of membrane lipids
- phospholipids
- glycolipids
- archaebacterial ether lipids
What is the structure of triacylglcerols
a glycerol bound to three fatty acids
Are triacylglycerols polar or nonpolar
nonpolar
Why do fats carry more energy per carbon than polysaccharides
because they are more reduced
Which is for quick delivery of energy? fatty acids or polysaccharides
polysaccharides
What makes up glycerophospholipids
- Glycerol (3 binding sites)
- Two attached Fatty acids bound to glycerol
- a phosphate that can have an alcohol added to it
What kind of fatty acid is usually added to the C2 of a glycerophospholipid
a UNsaturated fatty acid
A glycerophospholipid usually has two fatty acids (C2 usually has an unsaturated fatty acid), what else is bound to it
a phosphate group
what is usually added to the phosphate group of a glycerophospholipid
an alcohol
What is the name for substituent groups added onto the glycerol that aren’t fatty acids
head groups
Where is phosphatidylcholine used
it is the major component of most eukaryotic cell membranes
What is phosphatidylcholine
a glycerophospholipid with a choline as the head group
What is phosphatidylethanolamine
a glycerophospholipid that has ethanolamine (C2,N,H3) as the head group
Is plasmalogen an ether lipid?
yes
what is the structure of plasmalogen like in comparison to phosphatidylethanolamine
plasmalogen is the vinyl ether analog of phosphatidylethanolamine. The glycerol has an ether attached to one of it’s carbons as opposed to an ester like normal
Where is plasmalogen commonly found
heart tissue of vertebrates
how well is the function of plasmalogen understood
it is not well understood.
how easily is plasmalogen cleaved
not very easily, it is resistant to cleavage by common enzymes, but a few specific lipases can
What MAY be some possible functions of plasmalogen
- increase membrane rigidity
- source of signaling lipids
- antioxidants
What is the difference between sphingolipids and glycerophospholipids
the backbone of sphingolipids isn’t glycerol, its sphingosine
What are the main differences between sphingosine and glycerol
- sphingosine only has two spots where things can bind (it has a long-chain amino alcohol instead of a third space for binding)
- the fatty acid is joined by amide linkage, not ester linkage
What king of fat is sphingomyelin
a sphingolipid
What is the structure of sphingomylin like
- a sphingosine
- amide linked fatty acid
- phosphocholine head group
Where do we find sphingomyelin
in the myelin sheath that surrounds some nerve cells
Why do fats carry less water than polysaccharides
because they are non-polar
When do we use glycogen and glucose as energy sources
in short term energy needs, with a quick delivery
Are fats for long term storage or short
long term
is the delivery of fats into energy fast or slow
it is a slow delivery