Bio 5 MCQ & SEQ PDF

Biochemistry Questions LECTURE (5) - MCQ & SEQ DR. El-Sawy 1  Biochemistry Que...

Biochemistry Questions LECTURE (5) - MCQ & SEQ DR. El-Sawy 1  Biochemistry Questions 1) Which lipid most associated with cell membrane: a. Wax b. Sterol C c. Phospholipid d. Triglyceride 2) Sphingosine base is present in: a. Cerebrosides b. Gangliosides D c. Sphingomyelin d. All of the above 3) Glycerol is used for the synthesis of all except: a. Phosphatidic acid b. Lecithin C c. Glycolipids d. Triacylglycerol 4) Which nitrogenous base of the following is present in Lecithin? a. Choline b. Adenine A c. Ethanolamine d. Any of the above 5) Cephalin consists of: a. Glycerol, fatty acids, phosphoric acid and choline b. Glycerol, fatty acids, phosphoric acid and ethanolamine B c. Glycerol, fatty acids, phosphoric acid and inositol d. Glycerol, fatty acids, phosphoric acid and betaine DR. El-Sawy 2  Biochemistry Questions 6) The importance of phospholipids as constituent of cell membrane because they possess: a. Fatty acids B b. Both polar and non-polar groups c. Glycerol d. Phosphoric acid 7) Gangliosides are complex glycosphingolipids found in a. Liver b. Brain B c. Kidney d. Muscle 8) The nitrogenous base in lecithin is: a. Ethanol amine b. Choline B c. Serine d. Betaine 9) Dipalmitoyl lecithin acts as: a. Platelet activating factor b. Second messenger for hormones C c. Lung surfactant d. Anti-ketogenic compound 10) Cerebrosides contain all the following except: a. Galactose b. Sulphate B c. Sphingosine d. Fatty acid DR. El-Sawy 3  Biochemistry Questions 11) Sphingomyelins is : a. Phospholipids b. Nitrolipids A c. Alcohols d. None of the above 12) The deficiency of lung surfactant, Dipalmitoyl lecithin (DPL) causes Respiratory distress syndrome, DPL is a a. Cerebroside C b. Ganglioside c. Phospholipid d. Lipoprotein 13) Lecithin contains a nitrogenous base named as: a. Ethanolamine b. Choline B c. Inositol d. All the above 14) Lecithin combines with protein to form: a. Phosphoprotein b. Mucoprotein C c. Lipoprotein d. Glycoprotein 15) Sphingomyelins contain a complex amino alcohol named as: a. Serine b. Lysolecithin C c. Sphingosine d. Glycol DR. El-Sawy 4  Biochemistry Questions 16) Glycolipids contain an amino alcohol: a. Sphingosine b. Iso-sphingosine A c. Both (A) and (B) d. None of the above 17) Cerebrosides is classified as: a. Sphingolipids b. Sulpholipids D c. Aminolipids d. Glycolipids 18) Carbohydrate In cerebroside is usually a. Inulin b. Sucrose C c. Galactose d. Maltose 19) Lecithins are composed of: a. Glycerol + Fatty acids + Phosphoric acid +Choline b. Glycerol + Fatly acids + Phosphoric acid +Ethanolamine A c. Glycerol + Fatly acids + Phosphoric acid -t-Serine d. Glycerol + Fatty acids + Phosphoric acid +Betaine 20) Sphingomyelins are composed of fatty acids, phosphoric acid and: a. Sphingosine and choline b. Glycerol and sphingosine A c. Glycerol and Serine d. Glycerol and Choline DR. El-Sawy 5  Biochemistry Questions 21) When choline of Lecithin is replaced by ethanolamine the product is a. Sphingomyelin b. Cephalin B c. Plasmalogens d. Lysolecithin 22) Which one of the following is not a phospholipid? a. Lecithin b. Plasmalogens D c. Lysolecithin d. Gangliosides 23) In cephalin, choline is replaced by: a. Inositol b. Eithanolamine B c. Betaine d. Sphingosine 24) Sphingomyelins on hydrolysis yields: a. Glycerol. Fatty acids, phosphoric acid and choline b. Glycerol, sphingosine, choline and fatty acids D c. Sphingosine, phosphoric acid, Glycerol and inositol d. Sphingosine, fatty acids, phosphoric acid and choline 25) Phosphtidic acid on hydrolysis yields: a. Glycerol, fatty acids, phosphoric acid, choline b. Glycerol, fatty acids, phosphoric acid B c. Glycerol, fatty acids, phosphoric acid, Glucose d. Sphingol, fatty acids, phosphoric acid DR. El-Sawy 6  Biochemistry Questions 26) Cerebrosides are composed of: a. Sphingosine, fatty acids, glycerol and phosphoric acid b. Sphingosine, fatty acids, galactose B c. Glycerol, fatty acids, galactose d. Glycerol, fatly acids, galactose, sphingol 27) Phospholipid acting as surfactant is a. Cephalin b. Phosphatidyl inositol C c. Lecithin (DPL) d. Phosphatidyl serine 28) Lipoprotein present in cell membrane is by nature: a. Hydrophilic b. Hydrophobic C c. Both (A) and (B) d. None of these 29) Which of the following is NOT a constituent of gangliosides? a. Glycerol b. Oligosaccharide A c. Sphingosine d. Long chain fatty acid 30) Addition of choline to phosphatidic acid produces: a. Lysolecithin b. Phosphatidyl serine D c. Plasmalogen d. Lecithin DR. El-Sawy 7  Biochemistry Questions 31) Hydrolysis of sphingomyelin produces all the following EXCEPT: a. fatty acid b. Serine B c. Sphingosine d. Phosphate 32) Which of the following is lungs surfactant? a. Dipalmitoyl cephalin b. Dipalmitoyl lecithin B c. Plasmalogen d. Cardiolipin e. Ceramide 33) Which of the following is NOT a phospholipid? a. Cerebroside b. Sphingomyelin A c. Cephalin d. Lecithin 34) Hydrolysis of lecithin yields the following products EXCEPT: a. Saturated fatty acid b. Choline D c. Glycerol d. Ethanolamine 35) All the following phospholipids contain choline EXCEPT: a. Lecithin b. Cephalin B c. Plasmalogen d. Sphingomyelin DR. El-Sawy 8  Biochemistry Questions 36) The following conjugated lipids contain glycerol EXCEPT: a. Lecithin b. Cephalin D c. Plasmalogen d. Cerebroside 37) Second messenger for hormonal action is derived from: a. Phosphatidyl Choline b. Phosphatidyl Serine D c. Phosphatidyl Ethanolamine d. Phosphatidyl inositol DR. El-Sawy 9  Biochemistry Questions 1) The major lipid in chylomicrons is: a. Triglycerides b. Phospholipids A c. Cholesterol d. Free fatty acids 2) Endogenously synthesized triacylglycerols are transported from liver to extra hepatic tissues by which of the following lipoproteins? a. Chylomicrons B b. VLDL c. LDL d. HDL 3) The highest phospholipid content is found in: a. Chylomicron b. VLDL D c. LDL d. HDL 4) Free fatty acids are transported in the blood: a. Combined with albumin b. Combined with Fatty acid binding protein A c. Combined with α-lipoprotein d. In unbound Free salts 5) Cholesterol transported from liver to extrahepatic a. Chylomicrons b. VLDL D c. HDL d. LDL DR. El-Sawy 10  Biochemistry Questions 6) Elevated plasma level of following protects against atherosclerosis: a. Chylomicrons b. VLDL C c. HDL d. LDL 7) This lipoprotein removes cholesterol from the body: a. HDL b. VLDL A c. HDL d. Chylomicrons 8) The lipoprotein richest in cholesterol is a. Chylomicrons b. VLDL C c. LDL d. HDL 9) The following are plasma lipoproteins EXCEPT: a. Chylomicrons b. Very low-density lipoproteins (VLDL) D c. Low density lipoproteins (LDL) d. Very high-density lipoproteins (VHDL) e. High density lipoproteins (HDL) 10) Dietary fats are transported as a. Chylomicrons b. Liposomes A c. Lipid globules d. Oil droplets DR. El-Sawy 11  Biochemistry Questions 11) Main lipoprotein transporter of cholesterol from liver to tissues is: a. Chylomicron. b. VLDL. C c. LDL. d. HDL. 12) The main lipoprotein transporter of phospholipids is: a. Chylomicron. b. VLDL. D c. LDL. d. HDL. 13) The protein part of lipoprotein is known as: a. Apoprotein b. Pre-protein A c. Post-protein d. Pseudo protein 14) The class of lipoproteins having a beneficial effect in atherosclerosis is a. Low density of lipoproteins C b. Very low-density lipoproteins c. High density lipoproteins d. Chylomicrons 15) The density of lipoproteins increases as the protein content a. Increases b. Decreases A c. Highly decreases d. Slightly and promptly decreases DR. El-Sawy 12  Biochemistry Questions Define compound lipids and give examples?  Compounds consist of fatty acids + alcohols + other groups. Phosphoric acids Sugars Sulfate Protein Phospholipids Glycolipids Sulfolipids Lipoproteins Structure and types of phospholipids? Structure  Fatty acids, Alcohol, phosphoric acid ± nitrogenous base. Phosphoglycerides Glycerol  (Glycero-phospholipids) Types Sphingomyelin Sphingol (sphingosine)  (Sphingo-phospholipids) Structure and functions of Sphingomyelin 1. Sphingosine base. 3. Phosphoric acid. Structure 2. Unsaturated fatty acid. 4. Choline base. Function  Form myelin sheath which is electric insulator. Explain the value of amphipathic (hydrophilic part + hydrophobic part) ? Formation of lipid bilayer in cell membrane. Help T.G absorption in small intestine (micelle). Help T.G transport in blood (lipoprotein). DR. El-Sawy 13  Biochemistry Questions Compare ( ) Phosphatidic acid Lecithin Cephalin Other Phosphatidyl serine or Phosphatidyl choline name ethanolamine  Glycerol. Phosphatidic acid  2 fatty acid. Phosphatidic acid + Structure  Phosphoric acid. + serine or  No nitrogenous Choline. ethanolamine. base Compare ( ) Phospatidyl Plasmalogens Cardiolipin Inositol Other Diphosphatidyl Lipoinositol name glycerol Lecithin or Cephalin Phosphatedic acid but fatty acid at C1 2 Phosphatidic acid + Structure + of glycerol is Glycerol Inositol. replaced by unsaturated alcohol. How does Di-palmitoyl lecithin (DPL) prevent lung collapse : In pre-mature infant the lung alveoli do not secrete lecithin in sufficient amount  lung collapse ( respiratory distress syndrome ). DR. El-Sawy 14  Biochemistry Questions Enumerate functions of phospholipids? 1. They are amphipathic (hydrophilic part + hydrophobic part ). 2. Phosphatidic acid: intermediate compound in biosynthesis of other phosphoglycerides and triglycerides. 3. Lecithin  is a lipotropic agent that prevent fatty liver. 4. Di-palmitoyl lecithin (DPL) is lung surfactant (prevent lung collapse). 5. Cephalins: have a role in blood coagulation. 6. Plasmalogens: have a role in blood coagulation. 7. Cardiolipin  major lipid in mitochondrial membrane (Key role in mitochondrial structure and function) 8. Phosphatidyl inositol bisphosphate (PIP2)  2nd messenger for hormones. 9. Membrane phospholipids: provide arachidonic acid for synthesis of prostaglandins, leukotrienes. 10. Sphingomyelins: are abundant in the nervous system in the myelin sheath (act as electrical insulator). Compare ( ) Cerberosides Gangliosides 1. Sphingosine base. 2. long chain fatty acid. Types 3. Monosaccharide : 3. Oligosaccharide chain. Galactose (Galacto-cerebrosides) Glucose (Gluco-cerebrosides). Functio 1. Electrical insulator in nervous tissue. ns 2. Receptors for many hormones & cholera toxin. DR. El-Sawy 15  Biochemistry Questions Structure and functions of sulpholipids? Structure as cerberosides + sulphate group at C3 of galactose. Functions Present in brain & Nervous tissue. Functions of lipoprotein? 1. Structure of cell membrane 2. Lipid transport in blood "lipid are water insoluble so they can't Functions be transported alone, so lipids bind to protein make lipoprotein water soluble & can be transported in blood". Structure of lipiporotein? Nonpolar core (hydrophobic): Outer layer (hydrophilic): 1. Triglycerides (TG). 1. Free cholesterol. 2. Cholesterol ester (CE). 2. Phospholipids. 3. Apoproteins. Compare between types of lipoprotein? DR. El-Sawy 16