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Q.1- Name the fused ring system present in cholesterol.

Answer-Cyclo-pentano-per hydro-phenanthrene ring.

Q.2- Which alcohol is generally present in waxes?                  

Answer-Cetyl alcohol.

Q.3- Name the vitamins which act as alcohols to esterify fatty acids.

Answer- Vitamin A and D.

Q.4- Spontaneous oxidation of polyunsaturated fatty acids present in the biological membranes is called —-                                       

Answer- Lipid peroxidation..

Q.5- Which glycolipid is abundantly present in the white matter of brain?

Answer- Galactosyl ceramide

Q.6- Which lipoprotein transports cholesterol from liver to peripheral tissues?

Answer-LDL (Low density Lipoprotein).

Q.7- Which reaction is catalysed by LCAT?                    

Answer-Esterification of cholesterol

Lecithin+ Cholesterol—-Lysolecithin +Ester cholesterol.

 Q.8- Name two tri-enoic fatty acids.                      

Answer-Alpha and gamma Linolenic acids.

 Q.9- Give two biologically significant features of Phospholipase A2

Answer-Required for release of Arachidonic acid for the formation of Eicosanoids and provides fatty acid for the esterification of cholesterol in reverse cholesterol transport.

 Q.10- Low dose of Aspirin promotes the relative increase in the synthesis of prostacyclins, Is it true or false ?

Answer- True

 Q.11-The surface tension of dietary fat droplets in the intestine is decreased by — ?

Answer- Phospholipids and bile salts.

 Q.12- What is the advantage of taking low dose Aspirin?

Answer- Prevents thrombus formation and is recommended to high risk patients or to those who have a family history of IHD.

 Q.13-In which form are the fats stored in the body for long-term storage of energy,

Answer- Triacyl glycerol.

 Q.14- While comparing the potential energy of lipids and carbohydrates on weight basis, is it correct to say that lipids provide considerably more energy than carbohydrates?

Answer- yes, it is correct. Lipids provided 9.5 K. cal/G  energy as compared to 4.0 K. cal/G produced from the complete oxidation of carbohydrates.

 Q.15- A child presented with hyperacusis, regression of milestones and progressive blindness. What could be the possible defect?

Answer-Tay Sach disease-GM2 Gangliosidosis, deficiency of Hexosaminidase A enzyme.

 Q.16- The fluidity of the biological membranes is increased by the increase/ decrease in the degree of unsaturation of the component fatty acids.            

Answer- Fluidity of the biological membranes is increased by increase in the degree of unsaturation of component fatty acids.

 Q.17- What are the uses of Liposomes?      

Answer- They act as drugcarriers for the specific target sites without causing side effects. Also used for gene therapy.

 Q.18- Which phospholipid in a reservoir for second messenger?     


 Q.19- Give two examples of unsaturated fatty acids      

Answer-Oleic. Linoleic,Linolenic acid etc.

 Q.20-What are sulfolipids and where are they present in the body?

Answer-Sulfated Galactosylceramides are sulfolipids and they are present abundantly in the nervous tissue.

 Q.21- What does the notation 18:0 signify?

Answer- Saturated fattyacid with 18 carbon atoms.

 Q.22- What are the components of a Glycero phospholipid?

Answer-Glycerol, two fatty acids, phosphoric acid, a nitrogenous base or other components

 Q.23- What are neutral lipids?

 Answer- Because they are uncharged, Acylglycerols (glycerides), cholesterol, and cholesteryl esters are termed neutral lipids.

 Q.24-What is an alpha carbon in a fatty acid?

 Answer-The carbon atoms adjacent to the carboxyl carbon.

 Q.25-Which fatty acid is present in Oxynervon?  

Answer-Hydroxy Nervonic acid.

 Q.26- What is the difference between Cervonic acid and Cerebronic acid?

Answer- Cervonic acid is polyunsaturated fatty acid while Cerebronic acid is Hydroxy fatty acid.

 Q.27-Which of the following is an animal sterol?

Ergo sterol, Stigma sterol, Sitosterol, Cholesterol               

Answer- Cholesterol.

 Q.28-Which of the following contains a five membered ring-?

Plasmalogen,Glycolipids, Sphingomyelin and Prostaglandins


 Q.29-Prostacyclins increase the concentration of c- AMP, is it true or false?

Answer- It is true.

 Q.30-What is the cause of osmotic diarrhoea after PG( Prostaglandin) administration?

Answer -There is PG induced increase in the volume of pancreatic and Intestinal secretions resulting in osmotic diarrhea.

 Q.31-What are the components of a triacylglycerol?

Answer-Glycerol+ 3 fatty acids.

 Q.32-Name the different kinds of lipases present in the human body ?

Answer- Lingual, gastric, pancreatic and intestinal lipases are digestive lipases for the digestion of triacylglycerols, while there are phospholipases of different kinds besides hormone sensitive lipase present in the adipose tissue and Lipoprotein lipase for the digestion of lipoproteins.

 Q.33-What are the sources of fatty acids?

 Answer- Diet, Endogenous synthesis and derived from adipose tissue by adipolysis.

 Q.34-At which position is the fatty acid attached to the cholesterol ring,?

Answer- 3 rd position (Esterified to OH group present at the 3rdposition).

 Q.35-What is the product of a reaction of a fatty acid with alkali ?

 Answer-  Salt. This property is used for soap formation and for cleaning the chocked drains using an alkali.

 Q.36-Define rancidity.

Answer-The unpleasant taste and odour developed by fats on ageing is called rancidity.

 Q.37-What are the components of Slow releasing/Reacting substance of Anaphylaxis ?

Answer-LTC4, LTD4 and LTE4.

 Q.38-What is the site of cleavage of Sphingomyelinase enzyme?

Answer-Removal of phosphoryl choline from ceramide

 Q.39-Based on the nature of fatty acids present, how many types of Cerebrosides are there in the human system?

Answer- 4 types- Kerasin (Lignoceric acid), Cerebron (Cerebronicacid), Nervon (Nervonic acid) and Oxynervon (Hydroxy derivative of Nervonic acid ).

 Q.40-Which out of the two COX enzymes I and II is inducible?

Answer- It is COX II.

 Q.41- Name a sphingolipid                                            


 Q.42-All are conditions of hypercholesterolemia except

Anemia,Diabetes Mellitus, Hypothyroidism, Nephrotic syndrome

Answer- Anemia, there is low cholesterol level in blood.

 Q.43-Name a selective COX inhibitor                            

Answer- Celecoxib and Rofecoxib.

 Q.44-Name the drugs which can inhibit Prostaglandin synthesis

Answer- Steroids and NSAIDs.

 Q.45-Give the therapeutic uses of PGs

Answer-Termination of pregnancy, Treatment of asthma hypertension etc.

 Q.46-Why do oils float on the surface of water?

Answer-Oils have lesser specific gravity than water.

 Q.47-What is the systematic name of Alpha Linolenic acid

Answer- all cis- octadectrienoic acid-18;∆3, 9,12,15.

 Q.48-What is the main function of HDL?

 Answer- Transportation of cholesterol from peripheral tissues to liver, It is called Good cholesterol.

 Q.49-Butter is rich in short and medium chain fatty acids, Is it True or false?

Answer- It is true.

 Q.50-Name the disease caused due to deficiency of Beta Glucosidase enzyme .

Answer-Gaucher’s disease.

 Q.51-What is the difference between Cerebrosides and Globosides?

Answer-Cerebrosides contain a single monosaccharide while Globosides contain more than one monosaccharide; it may be Lactosyl oroligosaccharide ceramide.

 Q.52-Which phospholipid is present in the mitochondrial membrane?


 Q.53-Which phospholipid has unsaturated long chain alcohol in ether linkage  with the first hydroxyl group of glycerol ?                                         

Answer- Plasmalogen.

 Q.54-What is the basis of removing grease stains with petrol?

Answer-Petrol is an organic solvent, and grease is a wax. Petrol makes a soluble complex with grease.

 Q.55-What are the clinical manifestations in Essential fatty acids deficiency?

 Answer- Growth retardation,dermatitis, fatty liver and impaired vision.

 Q.56-Why are prostaglandins not conventionally used as drugs?

Answer-Short duration of action, rapidly destroyed and non specific in action.

 Q.57- Name the compound lipids.

Answer-Phospholipids, glycolipids, sulfolipids, amino lipids and lipoproteins.

 Q.58-Name any odd chain fatty acid.          

Answer-Propionic acid, Valeric acid.

 Q.59-Why is alkali used for opening the choked drains?

Answer- Alkali causes Saponification of fats forming water soluble soaps resulting in reopening of the blocked drains.

 Q.60-Name the phospholipids which act as lipotropic agents

Answer- All but most importantly, Phosphatidyl choline,Phosphatidyl ethanolamine and Phosphatidyl Inositol.

 Q.61-What is the defect in Niemann pick’s disease?

Answer-Deficiency of Sphingomyelinase enzyme.

 Q.62-What is the diagnostic hall-mark of Gaucher disease ?

Answer-Presence of Gaucher cells in bone marrow aspiration biopsy

 Q.63-Infants placed on low-fat diet due to a variety of reasons generally develop skin rashes and other symptoms. What is the reason for it?  

Answer- Essential fatty acid deficiency.

 Q.64-Which out of the following is an inter mediate both for the synthesis of phospholipids and Triacylglycerols-

Diacylglycerol, Cholesterol, Choline , Inositol               

Answer- Diacyl glycerol.

 Q.65- What is the risk associated with increased levels of serum total cholesterol?     


 Q.66-Why is cyclo-oxygenase enzyme called the suicidal enzyme?

Answer-It catalyzes its self-destruction.

 Q.67-Namea saturated fatty acid with 18 carbon atoms abundantly present in the body tissues.                                                                   

Answer- Stearic acid.

 Q.68-Which   fatty acid should have the least melting point out of the followings?

Stearic acid, Arachidonic acid, Timnodonic acid            

Answer-Timnodonic acid, since it has five double bonds; more the degree of unsaturation, lesser is the melting point.

Q.69- A 3 year child was brought with hepatosplenomegaly and mental retardation. Biopsy revealed accumulation of sphingomyelin. What is the defect?

Answer The child is suffering from -Niemann Pick’s disease.

 Q.70-Name the polar derivative of cholesterol

Answer- Bile salts.

 Q.71-A female patient with 34 weeks of pregnancy has to under go Emergency caesarean section for the delivery of the baby but the L:S ratio of amniotic fluid is 1:1. What is the significance of this ratio and what is recommended to this female?

Answer-   L/S ratio should be >2-5:1 for adequate fetal lung maturity. In the given patient L/S ratio of 1: 1 indicates fetal lung immaturity, Injections of glucocorticoids are recommended for her..

 Q.72- What is meant by Total cholesterol? 

 Answer-Free cholesterol+ Esterified cholesterol.

 Q.73-Why can’t essential fatty acids be synthesized by the human body?

Answer- Humans lacks the enzyme to incorporate double bond between the existing double bond and the methyl end (ω end).

Q.74-Name a fatty acid with 18 carbon atoms and a single double bond in trans configuration                                               

Answer-Elaidic acid.

 Q.75-Why is LDLc called a bad cholesterol?                 

Answer- Since it transports cholesterol from liver to peripheral tissues and excess of LDL can result in atheroma formation increasing the risk for IHD, Stroke or Peripheral vascular disease.

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