Question | Answer |
Types of lipids | fatty acids and steriods |
types of steroids | cholesterol, bile salts, steroid hormones |
essential fatty acids | linoleic acid, linolenic acid, arachidonic acid |
what is an essential fatty acid? | Polyunsaturated fatty acids that the body cannot synthesize enough of, on its own. |
Boiling point of saturated fatty acids | Higher because the fatty acids fit close together in a regular pattern |
Boiling point of monounsaturated fatty acids... | Lower because the fatty acids have a kink (cis bond) that makes them not fit as closely together. |
Boiling point of polyunsaturated fatty acids... | Lowest because the fatty acids have multiple kinks (cis bonds) that make them not fit as closely together. |
Solubility of saturated fatty acids... | Least soluble because the chains fit together very closely (solids at room temperature) |
Solubility of monounsaturated fatty acids... | More soluble because the chains fit less closely together due to one double bond (liquids at room temperature) |
Solubility of polyunsaturated fatty acids... | Most soluble because the chains don't fit very closely together at all due to multiple double bonds (liquids at room temperature) |
Prostaglandins (Eicosaniods) | Hormone-like substances
Formed from arachidonic acid
Create inflammation and pain, raise or lower blood pressure, stimulate contraction or relaxation of the uterus during child birth |
Prostaglandin E | Has a ketone group on carbon 9, and a hydroxyl group on carbon 11 |
Prostaglandin F | Has 2 hydroxyl groups... one on carbon 9 the other on carbon 11 |
Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) | Block production of prostaglandins from arachidonic acid decreasing pain, fever, and inflammation |
Waxes | ester of a saturated fatty acid and long-chain alcohol (each containing 14-30 carbons)
Used for waterproofing |
Triacylglycerol Function | They are the major form of energy storage for animals |
Fat | A triacylglycerol that is solid at room temperature
Usually comes from animal sources |
Oil | A triacylglycerol that is usually liquid at room temperature.
Obtained from plant sources |
Catalyst for hydrogenation | Nickel catalyst |
Oxidation of fats and oils produces... | Short-chain fatty acids and aldehydes |
Hydrolysis of triacylglycerols produces... | Glycerol and 3 fatty acids |
Catalyst of hydrolysis | HCl, H2SO4, and lipases |
Saponification | fat or oil + strong base ==> glycerol +salts of fatty acids (soaps) |
When NaOH is used in saponification... | A solid soap is produced |
When KOH or polyunsaturated oils are used in saponification... | A softer, liquid soap is produced |
Diester | When a phosphoric acid forms an ester bond between itself and 2 hydroxyl groups of alcohols |
Lecithins | Glycerophopholipids containing choline |
Cephalins | Glycerophospholipids containing ethanolamine |
Glycerophospholipids are found in... | Brain and nerve tissues, egg yolks, wheat germ, and yeast
Most abundant lipids in cell membranes |
Polar "head" (hydrophillic) | Ionized amine and phosphate portion |
Nonpolar "tails" (hydrophobic) | Two fatty acids attached to glycerol |
Ceramide | The -NH2 group of sphingosine is attached by an amide link to a fatty acid |
Sphingomyelins | The -OH of a ceramide forms a phosphate ester of choline |
Function of sphingomyelins | To increase the speed of nerve impulses and to insulate and protect the nerve cells
Found in the white matter of myelin sheaths |
Cerebroside | Sphingolipids that have one monosaccharide forming a B-glycosidic bond with the -OH of the ceramide |
Function of cerebrosides | Present primarily in brain and myelin sheath
Important to cellular recognition and tissue immunity on the surface of cell membranes |
Ganglioside | A cerebroside that contains two to seven monosaccharides |
Function of ganglioside | Found in neurons of the brain and on the surface of cell membranes where they act as receptors for hormones, viruses, and certain drugs |
Steroids | Compounds containing the steroid nucleus (3 cyclohexane rings and rings and one cyclopentane ring) |
Cholesterol | Is a sterol because it contains an oxygen atom as a hydroxy group on carbon 3. |
The liver synthesizes cholesterol from... | Fats, carbohydrates, and proteins
There is no cholesterol in vegetable and plant products |
Bile Salts | Synthesized in the liver from cholesterol and stored in the gallbladder |
Function of bile salts | Breaking apart and emulsifying large globules of fat. Form larger surface areas for digestive enzymes. |
Lipoproteins | Spherical particles with an outer surface of polar proteins and glycerophospholipids that surround hundreds of nonpolar molecules of triacylglycerols and cholesteryl esters |
Function of lipoproteins | Form water-soluble complexes that can transport lipids through the blood stream. |
Very Low Density Lipoproteins (VLDL)
Cylomicrons | Transport triacylglycerols, glycerophospholipids, and cholesterol to tissues for storage or to muscles for energy. |
Low Density Lipoproteins (LDL)
"Bad Cholesterol" | Transport cholesterol to tissues to be used for the synthesis of cell membranes, steroid hormones, and bile salts.
When levels get high LDLs deposit cholesterol in arteries causing plaque build-up. |
High Density Lipoproteins (HDL)
"Good Cholesterol" | Remove excess cholesterol from tissues and carry it to the liver where it's eliminated.
Excess HDL is carried to the liver and eliminated. |
Adrenal Corticosteroids | Aldosterone, Cortisone, Prednisone |
Steroid Hormones | Testosterone, Androsterone, Estrogen, Progeterone |
Most of the glycerophopholipids in the lipid bilayer contain unsaturated fatty acids... | There are kinks because of the cis bonds, making the glycerophospholipids not fit very closely together making cell membranes fluid-like |
Function of cholesterol in cell membranes... | Provide structure and decrease flexibility |
Simple Diffusion | Ions and molecules go from high concentration to low concentration. Examples... O2, H2O, urea |
Facilitated Diffusion | Ions and molecules use integral proteins to go from high concentration to low concentration. Used for speed. Examples... Cl-, glucose |
Active Transport | Ions and molecules go from low concentration to high concentration. Requires energy (ATP). Examples... Na+, K+, Ca++ |
Estrogen | Aids in female sexual characteristics |
Testosterone | Aids in male sexual characteristics |
Progesterone | Prepares the uterus for a fertilized egg |
Norethindrone | Birth control pill |
Recommended cholesterol | Total ==> 200mg/dL. LDL ==> less than 130mg/dL. HDL==> greater than 40mg/dL. |
Omega 6 is found in... | Vegetables |
Omega 3 is found in... | Fish |
Functions of lipids | Structure, energy storage, chemical signals, protection, vitamins and pigments |