7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition The water-soluble B vitamins supply important components of numerous *1/1 coenzymes. All of the following are correct. EXCEPT. Mock Board Examination - Biochemistry and Nutrition Riboflavin- is a component of the redox coenzymes FMN and FAD Total points 53/75 Nicotinamide- is a component of redox coenzymes NAD and NADP Pantothenic acid- is a component of the carboxyl terminal prosthetic side chain Complete Name (Last Name, First Name, Middle Name) * Thiamin- participates in the decarboxylation of a-keto acids while folic acid and LEORAG, KIMBERLY ANN, ANTOLIJAO cobamide coenzymes function in one carbon metabolism Medical School * Wernicke encephalopathy results from a deficiency of vitamin B1 . Which *1/1 of the following represents classical symptoms associated with this disorder? UNIVERSITY OF CEBU SCHOOL OF MEDICINE Section * megaloblastic anemia ···/1 nausea, peripheral neuropathy, mental depression, ophthalmoplegia numbness, tingling, weakness, sore smooth tongue, anorexia, diarrhea, pallor of the Einstein skin and mucous membranes Newton weight loss, diarrhea, dementia, and dermatitis Gates Valoris Feedback Aziel Wernicke encephalopathy is most commonly found in chronic alcoholics due to their poor dietetic lifestyles. Wernicke encephalopathy is a syndrome characterized by ataxia, ophthalmoplegia, nystagmus, and confusion. If the disorder is left untreated, it will progress to Wernicke-Korsakoff syndrome which includes impairment of short-term memory, psychosis, coma, and eventually death. Lukans Excelsior Excelsus Eunoia Xavier No correct answers https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvUK… 1/38 https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvUK… 2/38 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition A 60-year-old chronic smoker and alcoholic man suffering from 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition Deficiency in which of the following vitamins is associated with *0/1 *1/1 progressive keratinization of the cornea? odynophagia, insomnia, epigastric discomfort, and recurrent diarrhea presented to the outpatient department. Clinical examination revealed memory disorientation, stomatitis, glossitis, esophagitis, and exfoliative dermatitis with some vesicles on erythematous bases on photoexposed A sites such as his hands shown in the attached image. These signs and symptoms are most likely the result of a deficiency in which of the C following vitamins? D E K Feedback The earliest symptoms of vitamin A deficiency are night blindness. Additional early symptoms include follicular hyperkeratosis, increased susceptibility to infection and cancer, and anemia equivalent to iron deficiency anemia. Prolonged lack of vitamin A leads to deterioration of the eye tissue through progressive keratinization of the cornea, a condition known as xerophthalmia. This enzyme is NOT required for the mobilization of glycogen * biotin cobalamin 1/1 glucose-6-phosphate dehydrogenase niacin glycogen phosphorylase riboflavin debranching enzyme thiamin phosphoglucomutase Correct answer niacin Feedback To mobilizing glycogen, three enzymes are required: glycogen phosphorylase debranching enzyme phosphoglucomutase https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvUK… 3/38 https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvUK… 4/38 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition The attached radiograph shows the typical bowed legs of an infant 7/1/23, 12:51 PM *1/1 Mock Board Examination - Biochemistry and Nutrition The end product of glycogenolysis * 0/1 suffering from a deficiency in which of the following vitamins? Glucose 6-phosphate Alanine Glycogen Lactate Pyruvate Correct answer Glucose 6-phosphate The parents of a 7-month-old infant bring their son to the pediatrician A because they have noticed that their child has a dull response to outside stimuli. In addition, they note that their child exhibits an exaggerated C startle response (sudden extension of arms and legs) to sharp sounds *1/1 and that he seems to be losing previously acquired motor and mental D skills. His pediatrician makes a diagnosis of Tay-Sachs disease. Elevated intracellular levels of which of the following carbohydrate-containing E compounds would provide useful information for confirmation of this K diagnosis? A. abnormal glycogen Feedback B. aldohexoses The main symptom of vitamin D deficiency in children is rickets. Rickets is characterized by improper mineralization during the development of the bones resulting in soft bones, muscle weakness (rickety myopathy or “floppy baby syndrome,”), and increased tendency for fractures (especially greenstick fractures). In toddlers with rickets, a common skeletal deformity is bowed legs as depicted in the radiograph. C. aldoketoses D. gangliosides E. glycosaminoglycans Feedback In Tay-Sachs disease, ganglioside GM2 is not catabolized. As a consequence, the ganglioside concentration is elevated. The functionally absent lysosomal enzyme is hexosaminidase A. The elevated GM2 results in irreversible brain damage to infants, who usually die before the age of 3 years. https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvUK… 5/38 https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvUK… 6/38 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition The enzyme deficient in Smith Lemli Opitz Syndrome * 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition Which of the following is associated with increased glucose uptake due 1/1 *1/1 to its ability to prevent phosphorylation of downstream effectors of the insulin-signaling cascade? NADH oxidase 7- Dehydrocholesterol reductase α-lipoic acid Arylsulfatase vitamin A Homogentisate oxidase vitamin D vitamin E vitamin K As the level of visceral fat increases there is a concomitant loss of *0/1 peripheral tissue responses to insulin. Adipose tissue responses to these metabolic changes includes a reduced secretion of which of the following Feedback adipokines? Lipoic acid (LA) is an essential cofactor for the E2 component of α-ketoacid dehydrogenase complexes, exclusively located in mitochondria. These include the PDH, α-ketoglutarate dehydrogenase (KGDH), and branched chain α-ketoacid dehydrogenase (BCKDH) complexes. Extensive evidence suggests that LA may have therapeutic usefulness in lowering blood glucose levels in diabetic conditions and that the intracellular redox status plays a role in the modulation of insulin resistance. Lipoic acid has been shown to stimulate glucose uptake by affecting components of the insulin-signaling pathway. Adiponectin Adipsin Leptin IL-6 Correct answer Adiponectin This glycogen storage disease is characterized by severe postabsorptive *1/1 hypoglycemia, hyperlipedemia, a cherub-like facies and lactic acidosis Andersen's disease Tarui's disease Von Gierke's disease McArdle's disease This glycogen storage disease is characterized by a deficiency in *1/1 phosphofructokinase Von Gierke's disease Andersen's disease McArdle's disease Tarui's disease https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvUK… 7/38 https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvUK… 8/38 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition A 6-year-old girl presented with moderate mental retardation with 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition The first step in the utilization of glucose * *1/1 difficulty with her vision. Physical examination shows a fair complexion and malar erythema and bilateral dislocated lenses. She has long, slender 1/1 Decarboxylation hands and fingers. Blood tests reveal her cystathionine concentration is below normal. Which amino acid is MOST likely to have an increased Phosphorylation urine concentration? Transamination Leucine Oxidation Methionine Arginine Feedback Alanine The first step in glycolysis is the phosphorylation of glucose by the enzyme Hexokinase Feedback This aldose is classified as a pentose * Dx. Homocystinuria- pathway involve conversion of homocysteine and serine to homoserine and cysteine Cysteine is formed from methionine, which is nutritionally essential. Following the connversion of methionine to homocysteine, homocysteine and serine form cystathionine, whose hydrolysis forms cysteine and homoserine. Harper’s p. 284-285 1/1 Glyceraldehyde Ribulose Erythrulose The primary pathway for the oxidation of glucose * Ribose 0/1 Mannose a. Embden Myerhoff pathway b. Sorbitol pathway The rate-limiting enzyme for the Pentose Phosphate Pathway * c. Tricarboxylic acid pathway d. Pentose phosphate pathway 1/1 Glycogen phosphorylase Correct answer Glucose-6-phosphate dehydrogenase a. Embden Myerhoff pathway Hexokinase Phosphofructokinase Rate limiting enzyme and the major regulatory enzyme in glycolysis * 1/1 triose phosphate isomerase glyceride 3-phosphate dehydrogenase phosphofructokinase aldolase https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvUK… 9/38 https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 10/38 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition Enzyme that links glycolysis and the citric acid cycle * 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition Which of the following biochemical pathways occur in both the cytosol 1/1 *1/1 and mitochondira? Pyruvate dehydrogenase I. Heme metabolism Isocitrate dehydrogenase II. Gluconeogenesis Alpha-ketoglutarate dehydrogenase III. Urea cycle Succinate dehydrogenase IV. Glycogen synthesis V. I and III are correct VI. I, II and III are correct Oxidative phosphorylation is carried out by respiratory assembly located *1/1 in a. mitochondrial matrix Feedback b. inner mitochondrial membrane Heme metabolism, urea cycle and gluconeogenesis occur in both the mitochondria and cytosol c. endoplasmic reticulum d. cytosol A patient had recurrent episodes of mild hemolytic anemia. Analysis of The following amino acid is GLYCOGENIC ONLY * *0/1 theses cells shows that they are highly sensitive to oxidative stress likely due to the fact that they contain significantly less glutathione than normal 1/1 erythrocytes, A deficiency in which of the following enzymes is LIKELY in these erythrocytes? aspartate Glutamate dehydrogenase isoleucine G-Glutamylcysteine synthetase leucine Ornithine decarboxylase lysine Cystathione synthetase tyrosine Correct answer G-Glutamylcysteine synthetase The hydrolysis of this disaccharide yields two molecules of glucose * 1/1 Maltose Sucrose Lactose Galactose https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 11/38 https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 12/38 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition The major glycosaminoglycan located in the cornea * 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition In prolonged starvation, how does the body supply the needed energy? * 0/1 1/1 The liver and kidneys significantly produce glucose through gluconeogenesis in Chondroitin sulfate order to supply the brain Heparan sulfate The liver stores of glycogen is degraded to supply glucose in the blood Keratan sulfate The lean muscle mass is degraded to supply the carbon necessary for Hyaluronic acid gluconeogenesis Dermatan sulfate The body produces ketones which become the main source of energy of the brain rather than glucose Heparin Correct answer Feedback Keratan sulfate A polysaccharide of fructose (a fructosan) found in tubers and roots of After the first day of starvation: The dominant metabolic processes are the breakdown of triacylglycerols in adipose tissue (lipolysis) and gluconeogenesis by the liver. The liver obtains energy for its own needs by oxidizing fatty acids released from adipose tissue. Muscle shifts almost entirely from glucose to fatty acids for fuel. - After three days: the brain begins to consume appreciable amounts of acetoacetate in place of glucose. About a third of the energy needs of the brain are met by ketone bodies - After several weeks of starvation, ketone bodies become the major fuel of the brain *1/1 dahlias, artichokes, and dandelions. It is used to determine the glomerular filtration rate Para-amino-hippuric acid (PAH) Which of the following amino acids is the precursor of niacin? * Inulin Glyceraldehyde 1/1 Tryptophan Evan's blue Glutamine Leucine The major glycosaminoglycan located in the mast cells * Tyrosine 1/1 Keratan sulfate Feedback Heparin 60 mg of tryptophan can be converted to 1 mg of niacin Heparan sulfate Chondroitin sulfate Dermatan sulfate Hyaluronic acid https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 13/38 https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 14/38 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition A 45-year-old man, a known alcoholic for at least the past 10 years, 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition What kind of linkage is hydrolyzed by glucosidase as part of its *0/1 *1/1 debranching enzyme role in glycogenolysis? reported to a physician for consultation. He complained of burning of eyes, a sore tongue, reduced appetite, and mild abdominal discomfort. Physical examination revealed cracks on the lips and in the corners of the Option 3 mouth; a red, fissured, and inflamed tongue; dull hair, oily skin, and split nails. A deficiency in which of the following vitamins would best explain Beta-1,6 glycosidic linkage the observed symptoms? Alpha-1,4 glycosidic linkage Alpha-1,6 glycosidic linkage biotin niacin pantothenate Feedback riboflavin The debranching enzyme has two catalytic sites in a single polypeptide chain. One is a glucan transferase that transfers a trisaccharide unit from one branch to the other, exposing the 1,6 branch point. The other is an alpha-1,6 glucosidase that catalyze the hydrolysis of the 1,6 glycoside bond to liberate the free glucose. thiamin Correct answer riboflavin What is the determinant of ABO antigen in blood typing? * Complex carbohydrates containing amino sugars and uronic acids. * 1/1 1/1 Sialic acid Oligosaccharide Phospholipids Sphingolipids Polysaccharides Nucleic acid Glycosaminoglycans Glycolipids Feedback The sequence of oligosaccharides determines whether the antigen is A, B, or O. https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 15/38 https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 16/38 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition A smear of your patients’ blood is shown in the following picture 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition A purine analog which is widely used in the treatment of gout * *1/1 1/1 demonstrating that the person suffers from a form of anemia. A deficiency in which of the following vitamins would lead to the anemia aspirin shown in the slide? azathioprine allopurinol 5-iododeoxyuridine 5-flourouracil Reduced glutathione (GSH) is composed of which of the following amino *1/1 acids EXCEPT? Cysteine B1 (thiamin) Glutamate B6 (pyridoxal phosphate) Glycine B12 (cobalamin) Serine biotin K Feedback Reduced glutathione is made of glutamate, cysteine, and glycine, and the gamma carboxyl group of the glutamate forms a peptide bond with the adjacent cysteine. It can also be called "gamma- glutamyl-cysteinyl-glycine" or gamma-ECG. Feedback Pernicious anemia is a megaloblastic anemia resulting from vitamin B12 deficiency that develops as a result of a lack of intrinsic factor in the stomach, leading to malabsorption of the vitamin. The anemia results from impaired DNA synthesis due to a block in purine and thymidine nucleotide biosynthesis. The block in nucleotide biosynthesis is a consequence of the effect of vitamin B12 on folate metabolism. When vitamin B12 is deficient, essentially all of the folate becomes trapped as the N5 -methyl-THF derivative as a result of the loss of functional methionine synthase. This trapping prevents the synthesis of other THF derivatives required for the purine and thymidine nucleotide biosynthesis pathways. The carbohydrate found in Blood type A * 1/1 Fucose Galactose N-acetyl-D-Galactosamine (GalNAc) D-Galactose https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 17/38 https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 18/38 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition THE INCREASE IN BLOOD GLUCOSE FROM THE INGESTION OF A 7/1/23, 12:51 PM *1/1 Mock Board Examination - Biochemistry and Nutrition A 23-year-old man has been consuming large quantities of raw egg SPECIFIC FOOD IN A GIVEN TIME PERIOD *0/1 whites as part of his current body-building routine. He has developed a rash and severe muscle pain. Blood work indicates he has anemia. His diet prevents intestinal absorption of a vitamin leading to inhibition in the Glycemic response synthesis of which of the following? Glycemic index fatty acid Glycemic allowance RNA Glycemic requirement DNA glycogen This principle states there is a 1:1 ratio of pyrimidine & purine bases *1/1 protein such that the Amount of guanine = cytosine and the Amount of Adenine = Correct answer thymine fatty acid Law of thermodynamics Central Dogma Chargaff's rule This phospholipid plays an essential role in reducing surface tension in *1/1 lung alveoli and preventing lung collapse Anfinssen's dogma Plasmalogen 3-phosphatidylethanolamine A PURINE BASE * 1/1 Cardiolipin Lecithin or phosphatidylcholines cytosine guanine uracil Feedback thymine Dipalmitoyl lecithin is a major constituent of the surfactant preventing adherence, due to surface tension, of the inner surfaces of the lungs. It is decreased in premature newborns and leads to respiratory distress syndrome. https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 19/38 https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 20/38 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition The active hormonal form of vitamin D requires several enzymatic steps. *1/1 The enzyme that catalyzes the breakdown of glycogen to glucose in the The final step in the synthesis of 1,25-dihydroxycholecalciferol occurs in liver and muscle *1/1 which of the following tissues? Glucose 6 phosphate dehydrogenase bone Hexokinase kidney Glycogen phosphorylase intestine Glycogen synthetase liver spleen Carbonic anhydrase requires which metal ion as cofactor * 0/1 Feedback iron Active calcitriol (1,25-dihydroxycholecalciferol) is derived from ergosterol (produced in plants) and from 7-dehydrocholesterol. Upon exposure to ultraviolet (UV) light from the sun and following thermal isomerization, 7-dehydrocholesterol is nonenzymatically converted to pre-vitamin D3 (cholecalciferol) which then enters the bloodstream and is taken up by the liver. In the liver cholecalciferol is hydroxylated at the 25 position by a specific D3 -25-hydroxylase generating 25-hydroxy-D3 [25-(OH)D3 ]. magnesium sodium zinc Conversion of 25-(OH)D3 to its biologically active form, calcitriol, occurs through the activity of a specific D3 -1-hydroxylase present in the proximal convoluted tubules of the kidneys. copper Correct answer zinc Serves as the carrier of genetic information to the site of protein *1/1 synthesis mRNA tRNA rRNA snRNA https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 21/38 https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 22/38 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition As the ER physician you are tending to a 59-year-old female patient who 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition You are tending to a patient in the emergency room (ER) who presents *1/1 has a broken left fibula. Upon physical exam you discover she also has with the following symptoms: nystagmus, organic toxic psychosis, and multiple bruises on her arms, legs, and upper torso. She also complains ataxia. You notice that the patient is dirty and appears not to have bathed of painful gums and significant bleeding whenever she brushes her teeth. in several days or weeks. There is an odor of vomit and alcohol on his She reports that she subsists on bouillon soup, tea, plain pasta, and clothing. Given the outward appearance and observed symptoms, your dinner rolls. Blood work indicates that she is mildly anemic with diagnosis is indicative of a deficiency in which of the following vitamins? *1/1 microcytic erythrocytes. Given these signs and symptoms, this patient most likely is suffering from the effects of a deficiency in the activity of biotin which of the following enzymes? folate branched-chain ketoacid dehydrogenase pantothenate lysyl hydroxylase riboflavin methionine synthase thiamin pyruvate dehydrogenase transketolase Feedback The symptoms observed in this patient are typical of Wernicke-Korsakoff syndrome. This disease is most commonly found in chronic alcoholics due to their poor dietetic lifestyles. This is characterized by the symptoms described as well as acute encephalopathy followed by chronic impairment of short-term memory. Persons afflicted with WernickeKorsakoff syndrome appear to have an inborn error of metabolism that is clinically important only when the diet is inadequate in thiamin. Feedback The signs and symptoms exhibited by this patient are indicative of scurvy which results from a deficiency of vitamin C (ascorbate). Vitamin C is a critical co-factor for the enzymes lysyl hydroxylase and prolyl hydroxylase that are required for the correct posttranslational modification of collagen. Loss of collagen processing leads to defective connective tissue synthesis and also results in poor platelet adhesion to exposed sub-endothelial extracellular matrix resulting prolonged bleeding time. Often times vitamin C deficient patients also exhibit mild anemia due to the role of vitamin C in the process of intestinal absorption of Fe2+ iron. This chemotherapeutic drug inhibits the enzyme thymidylate synthase * 1/1 Methotrexate Cytrabine Doxurubicin 5- fluorouracil (5-FU) Feedback 5-FLUOROURACIL INHIBITS THYMIDYLATE SYNTHASE https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 23/38 https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 24/38 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition 7/1/23, 12:51 PM Which of the following amino acids is the key gluconeogenic amino acid *0/1 Mock Board Examination - Biochemistry and Nutrition What is the major lipid found in both chylomicrons and VLDL? * 0/1 responsible for maintaining blood glucose levels during the early stages of fasting? Free fatty acids Cholesterol esters Glutamine Free cholesterol Aspartate Triglycerides Glutamate Correct answer Alanine Triglycerides Correct answer Alanine The purpose of the Cori cycle is to shift the metabolic burden in which of *1/1 the following directions? A 9-month-old child is presented to the emergency room by his parents *1/1 liver to brain who report that he has been vomiting and has severe diarrhea. The episodes of vomiting began when the parents started feeding their child brain to liver cow’s milk. The infant exhibits signs of failure to thrive, weight loss, hepatomegaly, and jaundice. Laboratory tests show elevated blood muscle to liver galactose, hypergalactosuria, and metabolic acidosis with coagulation liver to muscle deficiency. These clinical and laboratory findings are most consistent with a deficiency in which of the following enzymes? cardiac to skeletal muscle glucose-6-phosphate dehydrogenase Feedback fructokinase The Cori cycle represents a link between metabolic processes that occur in skeletal muscle and erythrocytes with those occurring in the liver. During anaerobic glycolysis in muscle the pyruvate is reduced to lactate. This pathway functions exclusively within erythrocytes because they lack mitochondria necessary for oxidation of NADH to NAD+. The lactate leaves these tissues, enters the blood, and is transported to the liver. Within the liver the lactate is oxidized to pyruvate and the pyruvate then serves as a substrate for glucose synthesis. The glucose leaves the liver and can be used by muscle and erythrocytes again. aldolase B fructose-1,6-bisphosphatase UDP-galactose uridyltransferase (GALT) https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 25/38 https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 26/38 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition The chemotherapeutic drug Methotrexate inhibits this enzyme * 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition What vitamin is deficient in a child presenting with craniotabes and bow legs? 1/1 *1/1 Thymidylate synthase Ascorbic acid HGPRTase 1,25 Dihydroxycholecalciferol Xanthine oxidease Alpha tocopherol Dihydrofolate reductase Menaquinone Feedback METHOTREXATE INHIBITS DIHYDROFOLATE REDUCTASE Major buffer in the Extracellular fluid * 1/1 Phosphate Ammonia An X-linked disease due to the absence of HGPRTase. It is characterized *1/1 by frequent episodes of uric acid lithiasis and a bizarre syndrome of self- Bicarbonate mutilation Calcium Alper's syndrome Von Gierke's disease Which of the following is NOT a plant based protein * Lesch Nyhan syndrome 0/1 Severe combined immunodeficiency (SCID) Tofu ADHD Egg Milk The protein found in raw egg white that inhibits biotin * Quinoa 0/1 Correct answer Casein Milk Albumin Avidin Lactoferrin Correct answer Avidin https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 27/38 https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 28/38 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition A cofactor of an important enzyme of the pentose phosphate pathway, 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition Functions as a cofactor to a carboxylase that acts on glutamate residues *0/1 *1/1 transketolase of clotting factor precursor proteins Biotin Biotin Riboflavin Vitamin A Thiamine Vitamin C Pantothenic acid Vitamiin E Niacin Vitamin K Correct answer Vitamin K A 45-year-old woman presented with a rash encircling her neck, diarrhea *0/1 and memory lapses. What vitamin is most likely deficient in this case? The earliest clinical symptom of Vitamin A deficiency * Thiamine 1/1 Niacin defective night vision Riboflavin Keratomalacia Biotin Xerosis conjunctivae Correct answer xerophtalmia Niacin presence of Bitots spots The most common vitamin deficiency in strict vegetarians * 1/1 The inherent absence of this enzyme prevents muscle glycogenolysis to *0/1 maintain glucose homeostasis Thiamine Folic acid glucose- 1- phosphatase Cyanocobalamin UDP-Glucose pyrophosphorylase Pantothenic acid glycogen phosphorylase glucose-6-phosphatase Correct answer Feedback glucose-6-phosphatase B12 or cyanocobalamin is deficient in strict vegetarians because it comes from meat sources https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 29/38 https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 30/38 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition The Watson-Crick model or the B-form of DNA is typified by * 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition Scurvy is due to a dietary deficiency of which vitamin? * 0/1 two single strands that run in the 5’ 3’ direction A bases located in the interior of the right-handed helix B6 (pyridoxal phosphate) a smaller number of purines than pyrimidines D 12 base pairs per helical turn B12 (cobalamin) 1/1 C Correct answer bases located in the interior of the right-handed helix Feedback DNA is distinguished from RNA by * Deficiency in vitamin C leads to the disease scurvy due to the role of the vitamin in the posttranslational modification of collagens. Scurvy is characterized by easily bruised skin, muscle fatigue, soft swollen gums, decreased wound healing and hemorrhaging, osteoporosis, and anemia. 1/1 its single stranded structure a high content of modified bases A 3-year-old child is diagnosed to have Hurler’s syndrome. The diagnosis *0/1 its component sugar, ribose of Hurler’s syndrome is MOST efficiently made by analyzing the patient’s the presence of thymine instead of uracil DNA for A region of DNA that does not encode RNA. A 6-year-old child was born at term, with no congenital anomalies. She is *0/1 now only 70% of normal body weight, though she shows dependent The entire set of genes in one leukocyte. A nucleotide substitution in the L-Iduronidase gene edema of the lower extremities as well as an enlarged abdomen. Her flaking skin shows irregular areas of depigmentation, hyperpigmentation, Alternative forms of the L-Iduronidase gene. and desquamation. These findings are most suggestive of which of the following nutritional problems? Correct answer Alternative forms of the L-Iduronidase gene. Marasmus Kwashiorkor Niacin deficiency This condition is also known as Mucopolysacharidoses Type I * 1/1 Vitamin A Deficiency Hurler's disease Correct answer Zellwegger disease Kwashiorkor Sanfilippo disease Hunter's disease https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 31/38 https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 32/38 7/1/23, 12:51 PM Mock Board Examination - Biochemistry and Nutrition A patient presented with hypogonadism and cardiomyopathy. Work up *0/1 revealed Juvenile hemochromatosis. This disorder results from a defect in the gene encoding the hemojuvelin protein. The expression of which of the following proteins would likely be unregulated in this patient? Hephaestin Hepcidin Ferroportin Transferrin receptor Correct answer Hepcidin The vitamin involved in biochemical reactions concerned with the transfer *0/1 of methyl, methylene, or formyl groups is a derivative of which of the following vitamins? α-lipoic acid biotin folic acid pyridoxine riboflavin Correct answer folic acid Quilgo Test ID * This question is filled automatically ✋ DO NOT EDIT OR REMOVE LEORAG, KIMBERLY ANN, ANTOLIJAO This content is neither created nor endorsed by Google. - Terms of Service - Privacy Policy Forms https://docs.google.com/forms/d/e/1FAIpQLScmXsVErHrhWB4QD1AWj8thw1QjeLaujb8hBAwXRF4FuCHAvw/viewscore?viewscore=AE0zAgDKvU… 33/38
