Chapter 10 Lipids Flashcards
What are lipids soluble in and NOT soluble in?
Soluble: in non polar solvents
NON soluble: H2O bc its amphipathic
What are some examples of lipids?
fats, oils, waxes, most non protein components of the membranes
What are 3 functions of lipids?
1) Major form of stored energy in biological systems
2) Major components of biological membranes
3) Hormones
Lipids are highly ______
saturated, because of the more protons the more energy can be derived rather than carbohydrates
______ can retain more water, so it has more storage capabilities than lipids
Glycogen
What are the 5 different types of lipids?
1) Fatty Acids: a common fuel
2) Triacylglycerols: storage form of fatty acids
3) Phospholipids: membrane lipids
4) Glycolipids: membrane lipids composed of carbohydrates attached to it
5) Steroids: polycyclic hydrocarbons with a variety of functions
What are the characteristics of fatty acids?
Long, unbranched, saturated (more hydrogens) chain carboxylic acid (AKA the head group)
What are fatty acids derived from?
From the hydrolysis of fats, vegetable oils or phosphodiacylglycerols of biological membranes.
Saturated fatty acid means?
No double bonds present
Unsaturated fatty acid means?
Double bonds are present
How do you number fatty acids?
The first carbon begins at the carboxylic acid end
Systemic naming of fatty acids
Octadecanoate
Means there are 18 C’s present with no double bonds (saturated) and -ate is the acidic part
Systemic naming of fatty acids
Octadecenoate
Means there are 18 C’s presents, with double bonds (Unsaturated) and -ate is the acidic part
Laurate—Saturated or unsaturated? # of C’s?
12 saturated
Myristate—Saturated or unsaturated? # of C’s?
14 saturated
Palmitate—Saturated or unsaturated? # of C’s?
16 saturated
Stearate—Saturated or unsaturated? # of C’s?
18 saturated
Arachidate—Saturated or unsaturated? # of C’s?
20 saturated
Arachidonate—Saturated or unsaturated? # of C’s?
20 UNsaturated
What is the effect of chain length on melting temperature?
Smaller/less compact/less C’s chain length, lower melting temp
Longer/more compact/ more C’s chain length, higher melting temp
What is the effect of unsaturation on melting temperature?
double bonds prevent tight packing, so LOWER temp
What are good fats?
high in cis polyunsaturated fats.
ex: vegetable oils, like olive, canola, sunflower
What are bad fats?
high in saturated fats.
ex: stearic (beef); palm & coconut oils (found in candy)
What are really bad fats?
trans fatty acids, result from partial hydrogenation of vegetable oils. Margarine has trans fatty acids.
This is because it is difficult to metabolism; lead to increased cholesterol
levels in the blood stream
What do omega 3’s do?
They help reduce the physical harm caused by smoking, reduce the risk of advanced prostate cancer, and helps your heart
How do you know if you have an omega 3 or omega 6?
Start counting from opposite side of the carboxylic acid and if the double bond starts on the 3 C from the end then it would be omega 3
What is a triacylglycerol?
It is a stored form of fatty acids and it contains 3 fatty acids + glycerol
Where are triacylglycerol’s located?
Located in adipocytes in adipose tissue
What are triacylglycerol’s function?
Store energy for a later use
Esterfication while making triacylglycerols
COOH reacts with the OH group
Saponification of triacylglycerols
reactions of glyceryl ester with sodium or potassium hydroxide to produce a soap, which is the corresponding salt of the long-chain fatty acid.
What can the backbone of phospholipids be?
Glycerol =glycerophospholipids or phosphoglycerides
Sphingosine= Sphingolipids
What are the four components of phospholipids?
2 fatty acids, glycerol or sphingosine (platform), phosphate group, and an OH group
Phospholipids with a glycerol platform are called _______?
phosphoglycerides or phosphoglycerols.
The major phospholipids are derived from ______?
phosphatidate
What is the most abundant group of lipids?
Phosphoglycerides which are derived from phosphatidic acid- palmitic, stearic and oleic acid
Phospholipids built on a sphingosine platform are called _________?
sphingolipids
Sphingomylein is a common membrane sphingolipid and is especially common in the ______?
myelin sheath of nerve cells
What are the four components of a sphingolipid?
Sphingosine, 1 fatty acid (attached by an amide bond), PO4, and choline
What are glycolipids?
They have a carbohydrate attached to lipids, which are embedded in membrane(lipid) and the carbohydrate is on surface of membrane. They also have a sphingosine backbone and is important with communication
What are glycolipids composed of?
Sphingosine backbone with fatty acid and sugar unit (carbohydrate)
What are steroids?
Hormones, Precursors of cholesterol, and are apart of membrane components
What is cholesterol and its function?
membrane component Precursor of bile Precursor of hormones (in charge of making hormones) Absent in prokaryotes Maintains membrane fluidity AMPHIPATHIC
What is so special about the membrane lipid from the archaeon?
archaeon can live in harsh conditions bc the arrangement of fatty acids are used for insulation.
You have and ether as well as branched molecules of methyl groups which allow to live under extreme pH high temperatures. It is also able to avoid hydrolysis and oxidation of membranes
