Shared Flashcard Set

Details

Lipids
68K 12-01 Chem 101 Unit 8
68
Chemistry
Undergraduate 1
12/05/2011

Additional Chemistry Flashcards

 


 

Cards

Term
Lipid
Definition
group of biological molecules of varying composition that are all soluble in non polar solvents.
Term
Fatty Acid
Definition
Long hydrocarbon chains that ends with a carboxylic acid group. (-cooh)
Term
Saturated Fatty Acid
Definition
Long chain monocarboxylic acids. contain only carbon to carbon single bonds and carbon hydrogen bonds. General Formula CH3(CH2)nCOOH
Term
Unsaturated Fatty Acid
Definition
Long chain monocarboxylic acids that contain one or more carbon to carbon double or triple bonds.
Term
Phospholipid
Definition
Combination of a lipid and a phosphate group. Major form of lipid in cells.
Term
Phophogylceride
Definition
Phospholipids derived from a gylcerol.
Term
Steroid
Definition
nautrally occurring family of lipids. Every steroid contains the same 17 carbon skeleton that spans 4 fused rings. Also, two methyl groups.
Term
Cholesterol
Definition
A common fat like sterpid nased alcohol found in animal fats.
Term
Triglyceride (TG)
Definition
three mlecules of fatty acids esterfied to glycerol. Also called triacylglycerols.
Term
Gylcerol
Definition
liquid alcohol often found as a component of fat or triglycerides. structural backbone onto which fatty acids attatch.
Term
Lipoprotein
Definition
Combination of lipid(s) and a protein(s). transportation from of lipids in the bloodstream.
Term
Apolipoprotein
Definition
protein component found in plasma lipoproteins. The wide variety of apolipoproteins give each lipoprotein a unique composition.
Term
Adipose
Definition
fat stored within the body.
Term
Lipase
Definition
enzyme that hydrolyzes the ester linkage between glycerol and the fatty acids of triglycerides.
Term
Glycolipids
Definition
Combination of a lipid and a carbohydrate group. i.e. brain and nervous tissue.
Term
Functions of Steroids
Definition
critical component of membranes, important to maintain membrane fluidity.
serve as hormones
and intergral component of bile acids.
Term
What is the most important steroid in animals? Why?
Definition
Chloesterol, because it is a major component of cell membrane and provides membrane fluidity.
Term
Cortisol
Definition
hormone secreted by the adrenal glad, helps the body deal with stress by raising glucose levels, increasing lipolysis, and depressing the immune system.
Term
anabolic steroids
Definition
resemble testosterone, artificially stimulate the body to increase the amount of muscle mass, stimule the healing of muscle and incress competitive aggressiveness.
Term
Major Lipids of the body
Definition
fatty acid, glycerol, cholesterol, phospholipids, monoglycerides, diglycerides, fat soluble vitamins, steroids.
Term
How much does fat does the average person injest per day?
Definition
60-130g of fat, mostly in the form of triglycerides, human body absorbs nearly 100% of fats injested.
Term
What are lipids found in foods composed of?
Definition
98-99% triglyceride, of which 92-95% is fatty acid, the remainder is glycerol.
Term
Biosynthesized Lipids
Definition
Fatty acids are synthesized in the cytoplasm of the cells of the liver, kidney, brain, lung and adipose tissue.
Term
How are lipoproteins classifed?
Definition
Based upon their distinctly different densitites after high speed ultracentrifugation
Term
Chylomicrons
Definition
largest and least dense of the lipoprotein, formed after ingestion of dietary fat, in the intestinal mucosam, transport dietary lipids to the liver, causes lipemia.
Term
Very Low-Density Lipoproteins (VLDL)
Definition
synthesized in the liver, transport TGs produced in the liver to extrahepatic tissues.
Term
Low-Density Lipoproteins(LDL)
Definition
transport cholesterol and cholesteryl to peripheral tissues and regulate synthesis of cholesterol. "bad cholesterol".
Term
High-Density Lipoproteins (HDL)
Definition
synthesized in the liver, transports cholesterol back to the liver for excretion. smallest and most dense lipoprotein particle. "good cholesterol"
Term
Beta Oxidation Pathway Definition
Definition
series of biochemical reactions whihc fatty acids are completely oxidized in the mitochondrial matrix, resulting in significant amounts of ATP.
Term
Beta Oxidation STEPS
Definition
1)each fatty acid molecule is bound to a CoA molecule.
2)each passage results in the production of a single 2 carbon acetyl CoA and a new fatty acid CoA that has two fewer carbons.
3) the two carbon CoA are consumed in the Krebs Cycle and result in production of ATP.
Term
Other than ATP what is produced in the Beta Oxidation Pathway?
Definition
two high-energy electron carries (1 NADH + 1 FAD2H). They enter the mitochondrial electron transport change and are used to make more ATP
Term
What happens to excess Acetyl-CoA?
Definition
They are converted into molecules called ketone bodies.
Term
Ketone Bodies
Definition
Beta-Hydroxybutyrate, acetone, and acetoacetate. CAn be used as fuel by most tissues, and certain organs.
Term
Ketosis
Definition
Excess levels of ketone bodies in the bloodsream.
Term
CAuses of ketosis
Definition
low carb diet, starvation, uncontrolled diabetes mellitus.
Term
Ketoacidosis
Definition
often accompanies ketosis. Beta-hydroxybutyrate and acetoacetate are strong acids that can alter blood Ph.
Term
What are the steps involed in the anabolism of lipids?
Definition
The precuresor of synthesis is Acetyl-CoA, each molecule is made by the sequential addition of acetyl groups (2 carbons). Fatty acids can ezymatically combine with glycerol to make TGs
Term
Where does synthesis of fatty acids occur?
Definition
Within the cytosol of cells.
Term
Pancreatic Lipase
Definition
removes fatty acids from dietary lipids resulting in more polar compounds with ampipathic properties.
Term
Emulsification
Definition
polar agents cover small fat particles and prevent monoglycerides, free fatty acids and glycerol.
Term
Sources of Lipase within the body
Definition
Pancreas (primary source)
Salivary Galnds (lingual lipase)
Term
Clinical Significance of elevated Lipase
Definition
acute pancreatitis, pancreatic carcinoma.
Term
Test methodolgy of Lipase
Definition
Measures the fatty acid that is produced by the catalysis of Lipase.
Term
Chylomicron Remnant
Definition
remainder of chylomicrons after exposure to LPL
Term
about 95% of Bile acids are?
Definition
reabsorbed and reused by the liver to support bile production.
Term
Steps in the metabolism of Dietary Lipoproteins
Definition
1) new chylomicrons are secreted into the lymphatic ducts and enter the blood.
2) LPL hydrolyzes triglycerides in chylomicrons.
3) resulting fatty acids and glycerol are taken up by cells and used as energy.
4) excess fatty acids are re-esterfied into triglycerides for long-term storage.
Term
Steps in metabolism of lipoproteins of hepatic origin
Definition
1)VLDL is syntheszied in the liver and secreted into circulation where they undergo lipolysis.
2) VLDL loses core lipids causing dissociation and transfer of lipoproteins and phospholipids.
3) VLDL remnants are further transformed into LDL in the liver.
4) Once LDL is bound to receptors they are endocytosed and transported to the lysosome.
5) triglycerides in LDL are converted into free fatty acids and glycerol.
6) fatty acids are metabolized for energy.
7) free cholesterol is used for membrane biosynthesis.
Term
Reverse Cholesterol Pathway
Definition
mediated by HDL maintains cholesterol equilibrium.
excess cholesterol is transported back to the liver by HDL, where it is excreted into bile as free cholesterol, or excreted after being converted to bile acids.
Term
3 forms of Hyperlipidemia
Definition
Hypertriglyceridemia, Hypercholeserolemia, Hyperlipoproteinemia.
Term
Hypertriglyceridemia
Definition
elevated levels of TGs. Results from abnormal lipid metabolism or abormal forms of VLDL. Serum TG >500mg/dL
Term
Hypercholesterolemia
Definition
increased level of cholesterol. contributor to atherosclerosis and CAD. abnormally high serum LDL. Common inherited disorder caused by defective or absent LDL receptors.
Term
Hyperlipoproteinemia
Definition
increased level of specific lipoproteins. acquired or inherited. caused by underlying diseases, medications, genetic mutations, or poor diet.
Term
Hypolipoproteinemia
Definition
very rare condition caused by a decreased level of lipoprotein.
Term
Atherosclerosis
Definition
Deposition of lipids, especially cholesterol, in arterial walls.
Term
Atherosclerosis - Disease Process
Definition
1)lipid deposition starts with fatty streaks.
2) blood traveling causes small injuries that signal macrophage and platelets.
3) LDL brings cholesterol and a fibrous plaque develops.
4) LDL that has been modified is taken up by macrophages and transform into foam cells.
5) continuous injurt and repair leads to additonal narrowing and increased pressure causing disease.
Term
Coronary Artery Disease
Definition
major fibrous plaque develops in the artiers of the heart. (Heart Attack)
Term
Peripheral Vascular Disease
Definition
major fibrous plaque develops in the arteries of the arms or legs.
Term
Cerebrovascular disease
Definition
majorfibrous plaque develops in the vessels of the brain. (Stroke)
Term
What is the most common type of heart disease?
Definition
Coronary Artery Disease, it is the leading cause of death in both men and women in the US.
Term
What are the possible effects of reduced or cut-off blood supply to the heart?
Definition
Angina, HEart Attack aslo known as Acute Myocardial Infarction, HEart Failure, Arythmias.
Term
Elevated LDL and Triglyceride
Definition
high risk of cardiac disease.
Term
High HDL concentration
Definition
decreased risk of cardiac disease.
Term
Low HDL concentrations
Definition
increased risk of cardiac disease.
Term
Elevated Triglyceride
Definition
contributor to cardiac disease.
Term
Total Cholesterol - Enzymatic Method
Definition
quantitation of all the colesterol and colesterol esters present.
Term
PRinciple of Total Cholesterol
Definition
hydrolysis of cholesterol esters yiel cholesterol and free fatty acids. Oxidation of total cholesterol yields Hydrogen peroxide,which is oxidatively coupled to 4-aminoantipyrine. When peroxidase is added it forms a product that absorbs light at 500nm.
Term
Friedewald Formula Part 1:
Definition
VLDL cholesterol = Triglyceride / 5
Term
Friedewald Formula Part 2
Definition
LDL cholesterol = Total Cholesterol - (VLDL Cholesterol + HDL cholesterol.
Supporting users have an ad free experience!