BIOCHEM Flashcards
1
Q
JR, a maritime engineer, Filipino, consulted with a nutritionist for his dietary prescription and meal plan because he wanted to lose weight. He is 5’9” and weighs 95 kg. What is JR’s IBW?
A. 67 kg
B. 68 kg
C. 69 kg
D. 70 kg
A
B
2
Q
If he does light work, what is his PA?
A. 812 calories
B. 814 calories
C. 815 calories
D. 816 calories
A
D
3
Q
If JR’s TER is 2700 calories, what is the nutrient value for carbohydrates?
A. 300 g
B. 330 g
C. 335 g
D. 340 g
A
C
4
Q
On the day of consultation, JR ate the following for breakfast: 2 boiled eggs, 1 cup cow’s milk, and 4 slices of pan Americano. What is the total CHO, CHON, fats, and calories value of what he ate respectively?
A. 36 g – 14 g – 14 g – 322 cal
B. 70 g – 22 g – 18 g – 452 cal
C. 58 g – 22 g – 18 g – 482 cal
D. 30 g – 18 g – 14 g – 220 cal
A
C
5
Q
2 exchanges of cooked horse radish leaves are equivalent to
A. 1⁄2 cup
B. 1 cup
C. 1.5 cups
D. 2 cups
A
D
6
Q
A breastfeeding mother and her 1-week-old baby comes to you for help because of sore nipples. What should be the first thing you will do?
A. Observe how they breastfeed
B. Advise the mother to stop breastfeeding until her nipples heal
C. Give formula milk
D. Prescribe a pain reliever for the mother
A
A
7
Q
A characteristic property of porphyrins is the formation of complexes with metal ions bound to which of the atom of the pyrrole rings?
A. Carbon
B. Hydrogen
C. Nitrogen
D. Oxygen
A
C
8
Q
mother consults you about her 1-month-old baby who is exclusively breastfed and apparently well, but seems to be slow in gaining weight. Which of the following should you do first?
A. Inquire about the duration of feeding and feeding interval
B. Ask about urine and stool output of the baby
C. Evaluate and observe the baby’s latch and swallowing of milk
D. All the choices are correct
E. Only 2 choices are correc
A
D
9
Q
Acholuric jaundice is known as
A. hemolytic jaundice
B. hepatic jaundice
C. post hepatic jaundice
D. mixed hyperbilirubinemia
A
A
10
Q
Because breastmilk is the perfect nutrition for human babies, it is recommended that mothers breastfeed their newborns exclusively for how many months?
A. 4 months
B. 6 months
C. 8 months
D. 10 months
A
B
11
Q
Breastfeeding via direct latching may not be possible when
A. the mother needs to undergo surgery after giving birth
B. the baby is sick and needs antibiotics but is able to suckle
C. both choices are correct
D. neither of the choices are correct
A
C
12
Q
During protein synthesis, which of the following reads information in mRNA & transcribes the amino acid to a growing polypeptide chain?
A. Messenger RNA
B. Transfer RNA
C. Ribosomal RNA
D. Heterogeneous nuclear RNA
A
B
13
Q
Which vitamin is correct paired with the metabolic process and its associated function?
A. Biotin – beta-oxidation
B. Ascorbic acid – lipogenesis
C. Thiamin – pentose phosphate pathway
D. Pantothenic acid - gluconeogenesis
A
C
14
Q
Globin synthesis occurs in the cytoplasm of which of the following cells?
A. Erythroblast and normoblast
B. Normoblast and reticulocyte
C. Erythroblast and reticulocyte
D. Erythroblast and erythrocyte
A
B (chatgpt)
15
Q
How does the mismatch repair system distinguish between the parental (i.e. correct) DNA strand and the newly synthesized strand containing the mismatched base?
A. Guanine in the new strand of the helix is methylated at GATC
B. Thymine in the new strand of the helix is methylated at GATC
C. Guanine in the parental strand of the helix is methylated at GATC
D. Thymine in the parental strand of the helix is methylated at GATC
A
B
16
Q
Impaired glucuronyl transferase activity is observed in all of the following conditions, EXCEPT
A. physiologic jaundice of the newborn
B. Criggler-Najjar syndrome
C. Gilbert syndrome
D. Dubin-Johnson syndrome
A
A
17
Q
Normally, when there is high iron concentration in the blood, which of the following is correct?
A. Iron is stored as ferritin
B. Hepcidin destroys ferroportin
C. Transferrin transports iron in ferrous form
D. Ferroportin releases iron in ferric form
A
B
18
Q
The following are similarities between replication & transcription, EXCEPT
A. same direction of elongation
B. both make use of an RNA primer
C. direction of synthesis are the same
D. phases are similar in terms of initiation and elongation
A
B
19
Q
The highest concentration of immunoglobulins found in colostrum is noted during the first 24 hours after delivery, hence breastfeeding should be initiated as soon as possible after birth. What immunoglobulin is highest in breastmilk?
A. IgG
B. IgM
C. IgA
D. All have the same concentration at any given time
A
C
20
Q
The mother of your 24-hour-old newborn is worried that she doesn’t have breastmilk. What should you do?
A. Ask the mother to pump milk in between her baby’s feedings
B. Reassure the mother that she has milk and her baby’s stomach capacity is just about 5-7 ml
C. Give formula milk while the mother waits for her milk to “come in”
D. Give IV fluids to prevent dehydration
A
B
21
Q
The mother of your term newborn patient expired due to birth complications. Your first choice for your patient’s nutrition would be
A. donated fresh expressed breastmilk
B. pasteurized breastmilk
C. formula milk
D. all of the choices given
A
A
22
Q
This enzyme is involved in DNA repair
A. Polymerase alpha
B. Polymerase beta
C. Polymerase delta
D. DNA polymerase epsilon
A
B
23
Q
The lipid-insoluble vitamin is not strictly a vitamin since it can be synthesized in the body:
A. Vitamin
B. Vitamin D
C. Niacin
D. Thiamin
A
B
24
Q
Vitamin A deficiency initially presents with
A. night blindness
B. xerophthalmia
C. impaired immune response
D. loss of sensitivity to green light
A
D
25
What is the name of the DNA repair system in E. coli in which dual incisions are made in the damaged part of the double helix, and a 12-13 base segment is removed and replaced with new DNA?
A. Mismatch repair
B. ATP site repair
C. Base-excision repair
D. Nucleotide-excision repair
D
26
What is the primary action of methotrexate, a chemotherapeutic agent?
A. Displaces cells of folate
B. Inhibits synthesis of nucleotides
C. Inhibits cellular kinase activity
D. Inhibits phosphorylation of free bases
B
27
What will you teach to the mother of a 2-month-old patient who will be going back to work and wants to continue breastfeeding her baby every day?
A. She can pump milk while at the office if she feels like to
B. She has to express her breastmilk in their office’s comfort room
C. She can express milk around 40 minutes in an 8- hour shift
D. Store expressed breastmilk in a 2-door ref which lasts for a month
C
28
Which cellular process is inhibited by the toxin of Amanita palloides, a deadly mushroom?
A. Cell division
B. DNA synthesis
C. RNA splicing
D. RNA synthesis
D
29
Which form of vitamin K is endogenous to the human intestine?
A. Menadione
B. Phylloquinone
C. Menaquinone
D. Phytomenadione
C
30
Which of the following BEST describes Okazaki fragments?
A. Fragments of DNA attached to an inhibitor component
B. Fragments of DNA that are copied in direction away from replication fork
C. Fragments of continuous DNA which eventually are joined to form DNA
D. Synthesized from 5’ to 3’ & proceeds in same direction as replication fork
B
31
Which of the following brings about the control of hemoglobin synthesis?
A. Heme
B. ALA synthase
C. Heme synthase
D. Globin
B
32
Which of the following can have a negative effect on the volume of milk a mother can produce if not addressed appropriately?
A. Maternal weight
B. Infant’s birth weight
C. Giving infant formula
D. Maternal caloric intake
C
33
Which of the following directs the polypeptide’s ultimate destination in the cell?
A. Codons
B. Small peptides
C. Molecular chaperones
D. Signal recognition particles
D
34
Which of the following increases iron absorption?
A. Calcium
B. Coffee
C. Vitamin C
D. Gastrectomy
C
35
Which of the following is a ferrireductase found at the apical surface of enterocytes?
A. Ferroportin
B. DCYTB
C. Hepcidin
D. Ceruloplasmin
B
36
Which of the following is included as a step to successful breastfeeding?
A. Train the nurses only in breastfeeding skills necessary to implement the hospital’s breastfeeding policy
B. Help mothers initiate breastfeeding within 24 hours after birth
C. Practice rooming-in
D. Allow the use of artificial teats and pacifiers
C
37
Which of the following is NOT found in transfer RNA?
A. Unique bases
B. Codon
C. Amino acid arm
D. Enzyme recognition site
B
38
Which of the following phrase is correct with the iron state when this is transported through the blood?
A. Iron must be in ferric form always
B. Ferrous iron can also be transported
C. All the choices are correct
D. None of the choices are correct
A
39
Which of the following reactions is required for proofreading (i.e. correcting replication errors) during DNA replication by DNA polymerase III?
A. 3’-5’ exonuclease activity
B. 3’-5’ endonuclease activity
C. 5’-3’ exonuclease activity
D. 5’-3’ endonuclease activity
A
40
Which of the following vitamin, when deficient, may lead to hemolytic anemia?
A. B6
B. B12
C. E
D. K
C
41
Which of these constitute the second level of organization of DNA?
A. Nucleosome
B. Double helix DNA
C. Chromosome
D. Condensed metaphase chromosome
A
42
Which of these is a function of nonsense codons?
A. They base pair with the anticodons
B. They code for non-essential amino acids
C. They may be used in the cell as termination signals
D. They are responsible for degeneracy of the genetic code
C
43
Which of these is NOT a core histone involved in the packing of DNA?
A. H1
B. H2A
C. H3
D. H4
A
44
Which of these minerals can be found in enzymes as a prosthetic group?
A. Iodine
B. Selenium
C. Calcium
D. Magnesium
B
45
Which of these minerals serve/s as prosthetic groups in enzymes?
A. Cobalt and chromium
B. Copper and cobalt
C. Chromium and copper
D. Calcium and chromium
B
46
Which of these statements is true regarding ascorbic acid?
A. Enhances absorption of iron
B. Intake > 100 mg/day causes toxic syndromes
C. Deficiency states include dermatitis and diarrhea
D. Proven to prevent the common cold when given in high doses
A
47
Which phase of protein synthesis does the release of newly synthesized polypeptide take place?
A. Initiation
B. Release
C. Elongation
D. Termination
D
48
Which types of porphyrins are more abundant and are important?
A. Types I and II
B. Types II and III
C. Types I and III
C
49
Which vitamin – deficiency state is correctly paired?
A. Vitamin B6 – impaired wound healing
B. Vitamin D – impaired blood clotting
C. Vitamin B12 – synthesis of coenzyme A
D. Vitamin E – hemolytic anemia
D
50
Which vitamin B is functionally associated with glycogenolysis?
A. B1
B. B2
C. B6
D. B12
C
51
Which of the following are the most abundant free amino acid in plasma?
I. Alanine
II. Glutamine
III. Glycine
IV. Tyrosine
A. I and III
B. II and IV
C. I and II
D. III and IV
A
52
Which of the following statement(s) is/are correct regarding the biosynthesis of triacylglycerols?
I. Both glycerol and fatty acids must be activated by ATP before they can be incorporated into acylglycerols
II. Glycerol kinase catalyzes the activation of glycerol to triacylglycerol-3-phosphate
III. In muscle or adipose tissue, most of the glycerol-3-phosphate is formed from dihydroxyacetone phosphate by glycerol-3-phosphate dehydrogenase
IV. 1,2-diacylglycerol phosphate is considered as the common precursor in the biosynthesis of triacylglycerol and phosphoglycerol
A. I and III only
B. II and IV only
C. I, II, and III
D. I, II, III, and IV
A
53
For this item, arrange the steps of the biosynthesis of cholesterol in the correct order.
(1) Formation of isoprenoid units from mevalonate by loss of CO2
(2) Biosynthesis of mevalonate from acetyl-CoA
(3) Cyclization of squalene gives rise to lanosterol
(4) Condensation of six isoprenoid units forms squalene
A. 4,2,3,1
B. 2,1,4,3
C. 2,4,1,3
D. 3,2,1,4
B
54
End product in the catabolism of serine is
A. alpha-ketoglutarate
B. pyruvate
C. acetyl-CoA
D. glycine
D
55
A 30-year-old woman complains of fatigue, weight gain, and cold intolerance. She is diagnosed to have hypothyroidism (low level of thyroid hormones). Which of the following is a precursor of thyroid hormone?
A. Glutamine
B. Tryptophan
C. Tyrosine
D. Threonine
C
56
A 5-year-old child develops convulsions (seizures). After running some tests, the neurologist determines that he has epilepsy. He is then given benzodiazepine which promotes the activity of GABA. GABA is derived from glutamate by which of the following reactions?
A. Transamination
B. Decarboxylation
C. Deamination
D. Hydroxylation
B
57
A couple of African-American descent gives birth to a boy after an otherwise uneventful pregnancy. The infant is exceptionally fair skinned and has almost white hair. A postnatal screen will most likely reveal a deficiency of
A. tyrosine hydroxylase
B. tyrosinase
C. methionine synthase
D. cystathione-β-synthase
B
58
Among the statements presented, which is FALSE?
A. All products in amino acid catabolic pathway enter the citric acid cycle
B. Pyruvate can be a product of amino acid catabolism
C. Carbon skeletons can be diverted in ketogenesis but not gluconeogenesis
D. Transamination to urea is freely reversible
C
59
Apo E, via LDL receptor and the LRP, mediates
A. receptor-mediated endocytosis of chylomicrons in the liver
B. hydrolysis and metabolism of cholesteryl esters and triacylglycerols
C. both choices are correct
D. neither of the choices are correct
C (chatgpt)
60
In anaerobic conditions, glycolysis can produce a total of how many ATP per mol of glucose?
A. 4
B. 3
C. 2
D. 1
C
61
In mammalian tissue serine can be a biosynthetic precursor for which amino acid?
A. Methionine
B. Glycine
C. Arginine
D. Lysine
B
62
In the liver, what is considered as the most important activator of PFK-2 that controls the flux between the opposing pathways of glycolysis and gluconeogenesis?
A. Fructose-2,6-bisphosphate
B. Bisphosphoglycerate
C. Glucose-6-phosphate
D. Glyceraldehyde-3-phosphate
A
63
Problems with the acidic amino acid transport system which transports glutamic acid and aspartic acid can cause which of the following genetic disease?
A. Joseph syndrome
B. Cystinuria
C. Hartnup disease
D. Dicarboxylic aminoaciduria
D
64
S-adenosyl methionine is required for the synthesis of which of the following compounds?
A. Thyroid hormone
B. Epinephrine
C. Serotonin
D. Bile salts
B
65
The branching enzyme is essentially a
A. transferase
B. lyase
C. ligase
D. hydrolase
A
66
The debranching enzyme functions as which type of enzyme?
A. Transferase and lyase
B. Hydrolase and ligase
C. Transferase and hydrolase
D. Ligase and isomerase
C
67
These unsaturated fatty acids comprise lipoxins:
A. Polyunsaturated
B. Eicosanoids
C. Monounsaturated
D. A and B
B
68
This is the vehicle of uptake of cholesterol and cholesteryl esters into many tissues:
A. Total cholesterol
B. HDL
C. LDL
D. VLDL
C
69
Tissue-specific differences in the allosteric effectors reflect different function of glycolysis in various tissues. In tissues when ATP synthesis is the major function, PFK-1 is inhibited by _____ and activated by _____.
A. ATP; AMP
B. AMP; ATP
C. NADH; NAD
D. NAD; NADH
A
70
Triglycerides are esters of which of the following?
A. Fatty acids and oxygen atom
B. Glycerol and fatty acids
C. Carbon atom and fatty acids
D. Glycerol and cholesterol
B
71
Uridine diphosphate glucose (UDP-Glc) is an active form of glucose wherein its formation is highly favoured due to the activity of which enzyme?
A. Phosphoglucomutase
B. Pyrophosphatese
C. Pyrophosphorylase
D. Phosphorylase
B
72
Von Gierke’s disease causes hyperuricemia due to the accumulation of which of the following products in the glycogenolysis pathway?
A. Limit dextrins
B. UDP-glucose
C. Glucose-5-phosphate (G6P)
D. Glucose
C
73
What is the end product of glycogenolysis in the liver?
A. Glucose
B. Glucose-6-phosphate
C. Glucose-1-phosphate
D. Glucagon
A
74
What is the final product of nitrogen catabolism?
A. Ornithine
B. Nitrous oxide
C. Urea
D. Ammonia
C
75
What is the protein involved in the formation of lipid droplets in adipocytes, and inhibits lipolysis in basal conditions by preventing access of the lipase enzymes to the stored TAGs?
A. Ghrelin
B. Leptin
C. Insulin
D. Perilipin
D
76
What kind of reaction is produced when pyruvate dehydrogenase complex catalyzes a reaction to convert pyruvate into acetyl CoA?
A. Oxidative dephosphorylation
B. Oxidative decarboxylation
C. Hydrolysis
D. Phosphorolysis
B
77
What specific phospholipase is found in pancreatic fluid and snake venom as well as in many types of cells?
A. Phospholipase A1
B. Phospholipase A2
C. Phospholipase C
D. Phospholipase D
B
78
What unsaturated fatty acid occurs in oil of evening primrose?
A. Linolenic
B. Linoleic
C. Oleic
D. Timnodonic acid
A
79
When is the nuclear bile acid-binding receptor, farnesoid X receptor (FXR) activated?
A. When the bile acid pool in the enterohepatic circulation increases
B. When a portion of the secondary bile acids in the intestine is subjected by changes through the activity of the intestinal bacteria
C. When it is activated by insulin
D. When it is enhanced by endogenous
A
80
Which among the following is a secondary bile acid?
A. Cholic acid
B. Chenodeoxycholic acid
C. Coprostanol
D. Lithocholic acid
D
81
Which among the following statements is correct regarding glycolipids?
A. Galactosylceramide is the predominant simple glycosphingolipid of extraneural tissues
B. Glucosylceramide contains a number of characteristic C24 fatty acids like cerebronic acid
C. Sulfatide is present in high amounts of myelin
D. Gangliosides are complex glycosphingolipids derived from galactosylceramide that contain one or more glucosylceramide molecules of sialic acid
C
82
Which among the following statements is INCORRECT?
A. Cholesterol is present in tissues and in plasma either as free cholesterol
B. Cholesterol is combined with a long-chain fatty acid as cholesteryl ester, the storage form
C. Cholesterol is an amphiphilic lipid and an essential structural component of membranes
D. Cholesterol occurs in foods of animal origin such as egg yolk, meat, liver, and brain
C
83
Which among the following triacylglycerol and phosphoglycerol is derived from dihydroxyacetone phosphate?
A. Plasmalogen
B. Cardiolipin
C. Phosphatidylinositol
D. Phosphatidylcholine
A
84
Which of the following is indicative of the roles of ATP-binding cassette transporters?
A. These transporters are members of a family of transporter proteins that couple the hydrolysis of ADP to the binding of a substrate, enabling it to be transported across the membrane
B. ABCG1 mediates the transport of cholesterol from cells to HDL
C. ABCA1 preferentially promotes efflux to rich lapidated particles such as pre β-HDL or apo A-1, which are then converted to HDL3 via discoidal HDL
D. Pre β-HDL is the most potent form of HDL inducing cholesterol influx from the tissues
B
85
Which is TRUE among the statements regarding the degradation of specific proteins?
A. Long-lived intracellular proteins are degraded in the cytosol by ATP-dependent processes
B. Degradation of regulatory proteins with short half- lives requires ATP and ubiquitin
C. Degradation of misfolded proteins occurs in the proteasomes
D. Degradation of ubiquitin-tagged proteins takes place in the lysosomes
B
86
Which of the following are factors that enhance the synthesis of TAG and the secretion of VLDL by the liver?
A. Low insulin concentrations and high glucagon levels
B. High levels of circulating free fatty acids
C. The body in a starved state
D. The feeding of diets high in protein
B
87
Which of the following are true regarding the melting points of even-numbered carbon fatty acids?
A. Increase with chain length, decrease according to unsaturation
B. Increase in chain length, increase according to unsaturation
C. Decrease in chain length, decrease according to saturation
D. Decrease in chain length, increase according to saturation
A
88
Which of the following derivatives of phosphatidic acid is correctly paired to its description?
A. Lecithin – mitochondrial membranes
B. Cardiolipin – body store of choline
C. Plasmalogen – promotes atherosclerosis
D. Phosphoinositide – cell signalling
D
89
Which of the following enzymes are deficient in a glycogen storage disease where the juvenile onset variant is characterized by muscle hypotonia, heart failure, and death by age 2?
A. Glucose-6-phosphatase
B. Endoplasmic reticulum glucose-6-phosphate transporter
C. Lysosomal acid maltase
D. Hepatic phosphorylase
C
90
Which of the following enzymes catalyzes the most critical step in the breakdown of the main glucose storage form in liver and muscle tissue?
A. Debranching enzyme
B. Synthase
C. Phosphorylase
D. Phosphatase
C
91
Which of the following enzymes is activated by phosphorylation?
A. Glycogen synthase
B. Pyruvate kinase
C. Glycogen phosphorylase
D. Branching enzyme
C. Glycogen phosphorylase
92
Which of the following glycolytic enzymes do not require ATP to proceed with the reaction?
A. Hexokinase
B. Phosphofructokinase
C. Triose phosphate isomerase
D. Glucokinase
C
93
Which of the following is a co-factor of the enzyme DOPA decarboxylase in the formation of dopamine?
A. Copper
B. Pyridoxal phosphate
C. S-adenosyl methionine
D. Vitamin C
B
94
Which of the following is considered as one of the major functions of the liver in lipid metabolism?
A. It facilitates the digestion and absorption of lipids by the production of bile, which contains cholesterol and bile salts synthesized within the liver de novo or after uptake of lipoprotein cholesterol
B. It selectively synthesizes and oxidizes fatty acids and also synthesizes triacylglycerols and chylomicrons
C. It converts fatty acids to acetate bodies
D. It plays a supplementary role in the synthesis and metabolism of plasma lipoproteins
A
95
Which of the following is derived from the amino acid tryptophan?
A. Dopamine
B. Melanin
C. Melatonin
D. Tyrosine
C
96
Which of the following is responsible for the formation of the glycogen primer?
A. Glycogen synthase
B. Branching enzyme
C. Glycogenin
D. Debranching enzyme
C
97
Which of the following metabolite is capable of allosterically activating muscle glycogen phosphorylase BUT NOT the hepatic isoenzyme?
A. Glucose-6-phosphate
B. Glucose
C. ATP
D. 5’AMP
D
98
Which of the following statements about glutamate dehydrogenase is CORRECT?
A. Required for transamination reactions
B. Universally present in all cells of the body
C. Can utilize either NAD+ or NADP+
D. Catalyzes the conversion of glutamine to glutamate
C
99
Which of the following statements regarding cysteine is INCORRECT?
A. Carbon skeleton is provided by serine
B. Sulfur group is provided by methionine
C. Forms hippuric acid for detoxification of xenobiotics
D. Required for bile salt formation
C
100
Which saturated fatty acid is the main product of carbohydrate fermentation by rumen organisms?
A. Caproic
B. Stearic
C. Butyric
D. Acetic
D
101
Which of the following compounds transiently binds the substrate or enzyme in an enzyme-catalyzed reaction?
A. Cofactor
B. Coenzyme
C. proenzyme
D. prosthetic
A
102
Enzymes having slightly different molecular structures or physiologic properties but performing identical activity are
A. Proenzymes
B. Isoenzymes
C. Coenzymes
D. Isomers
B
103
Which of the following vitamins is/are essential in the Krebs cycle?
A. Thiamine
B. Pantothenic acid
C. Nicotinamide
D. All of the above
D
104
Which vitamin deficiency will most likely affect activity of the pyruvate dehydrogenase
A. Pantothenic acid
B. Pyridoxine
C. Folic acid
D. Thiamine
D
105
A newly isolated enzyme was being studied for its kinetic properties. When a substrate is bound to the enzyme, a significant conformational change occurred prior to the reaction undergoing completion. Once the product is released, the enzyme returns to its original conformation. Which of the following best summarizes the activity described?
A. Induced fit model of binding
B. Kinetic theory of chemical reactions
C. Proximity and approximately during catalysis
D. Lock and key model of binding
A
106
Which of the following groups of enzymes is present in the glycolytic pathway but not in the tricarboxylic cycle?
A. Oxidoreductase
B. Isomerase
C. Ligase
D. Lyase
B
107
Which of the following groups of enzyme is present in the tricarboxylic cycle but not in the glycolytic pathway:
A. Ligase
B. Oxidoreductase
C. Lyase
D. None of the above
A
108
Which major group of enzymes most likely catalyzes the following reaction (DEHYDRATION)?
A. Ligases
B. Hydrolases
C. Lyases
D. Transferases
E. NOTA
C (shopee)
E. (ENOLASE)
109
Which major groups of enzymes most likely catalyzes the following reaction? (Involves conversion of NAD to NADH)
A. Oxidoreductases
B. Transaminases
C. Lyases
D. Hydrolases
A
110
Which of the following oxidoreductases catalyze the following reaction? (Addition of O2)
A. Dehydrogenases
B. Peroxidase
C. Oxygenases
D. Oxidases
C
111
An enzyme with a Vmax of 20 mmol of product per minute milligram and a Km of 0.75 mM interacts with substrate levels of 0.25 mM during fasting. After feeding, the substrate levels increased to 1.25 mM. The reaction velocity of this process, comparing the feeding state to fasting state is which of the following?
A. 5
B. 2.5
C. 7
D. 12.5
B
112
What type of inhibitor was most likely added to this enzyme catalyzed reaction? (Inhibitor and non inhibitor meets at 0)
A. non-competitive
B. irreversible
C. competitive
D. uncompetitive
C
113
Which of the following is TRUE regarding this enzyme inhibition (does mot meet at 0)? The inhibitor
A. Lowers the Vmax of the enzyme as indicated by point B
B. Irreversibly binds to the active site
C. Binds to the substrate-enzyme complex as indicated by point A
D. Increases the affinity of the substrate to the enzyme
A
114
Which of the following enzymes allows cells to survive anoxic episodes?
A. Aldolase
B. Lactate dehydrogenase
C. Hexokinase
D. Pyruvate kinase
B
115
The three important properties of DNA polymerases are
A. Processivity, proofreading and ligation
B. Elongation, processivity, and proofreading
C. Unwinding, chain initiation and elongation
D. Chain initiation, elongation, and processivity
B
116
Which of the following is responsible for the concerted regulation between purine and pyrimidine nucleotide de novo pathways?
A. The allosteric enzyme control mechanisms in both pathways
B. The ability of the products in both pathways to inhibit the formation of PRPP
C. The involvement of common amino acid precursors and carbon dioxide in both pathways
D.The concerted catalytic activities of the multifunctional catalyst present in both pathways
B
117
The sunlight sensitivity and susceptibility to skin cancer in persons with Xeroderma Pigmentosum is due to the deficient activities of which DNA repair system?
A. Base excision repair system
B. Nucleotide excision repair system
C. Double strand break and repair system
D. Mismatch repair system
B
118
An important feature of the genetic code that may protect the codon in the event of a single base substitution
A. Degeneracy of genetic code
B. Universality of genetic code
C. Commaless of genetic code
D. Unambiguity of genetic code
A
119
True of transcription & translation but not for replication
A. Both are nuclear events
B. Both require DNA as template
C. Both need initiation protein factor
D. Both undergo post-transciptional modification
D
120
The so called "caps" of RNA molecules
A. Allow tRNA to be process
B. Are composed of Poly A
C. Occur at the 3'end of RNA
D. Are unique to eukaryotic mRNA
D
121
DNA polymerase only initiates replication only when this protein laid down molecules which provides 3’OH attachment for new deoxynucleotides
A. SSB
B. DNA A
C. DNA dependent RNA polymerase
D. Helicase
C
122
Termination codon is different from other codon in that they
A. Only recognize single trna
B. Only specify single amino acid
C. Bind to releasing factor instead of trna
D. Are capable of binding to many different trna
C
123
Which posttranslational modification is needed to protect native conformation of protein from denaturation?
A. Addition of prosthetic group
B. Methylation
C. Formation of S-S cross-link
D. Carboxylation
C
124
In lactose operon, which of the following occur?
A. A regulator gene produces an inactive repressor
B. The structural genes are coordinately expressed
C. The inducer binds to repressor protein and activates it
D. The inducer stimulates binding of RNA polymerase to the promoter
B
C (shopee)
125
The importance of TATA box is that it
A. DNA binding protein to this box enhances transcription
B. Promotes fidelity of transcription
C. Represses transcription
D. Dictates frequency of transcription
D
A (shopee)
126
Which of the following enzymes in replication functions as proof reading device?
A. 3' exonucleases
B. 5' exonucleases
C. Polymerase enzyme
D. Aminoacyl tRNA synthetase
A
127
It is involved in translation EXCEPT
A. Releasing factors
B. Holoenzyme
C. Elongation factors
D. Aminoacyl AMP
B
A (shopee)
128
A common characteristic of both replication and transcription
A. Formation of Okazaki Fragments
B. Enzymes act as proofreading device
C. Both strands serve as template simultaneously
D. Adherence to watson-crick base pairing rules
D
129
Phosphoglycerate kinase functions in carbohydrate metabolism to produce ATP by:
A. Oxidative phosphorylation
B. Oxidative decarboxylation
C. Phosphorylation
D. Substrate level phosphorylation
D
130
Which of the ff. oxidized ferric iron to ferrous iron?
A. Duodenal cytochrome B reductase
B. Hephaestin
C. Ceruloplasmin
D. Hepcidin
A
131
Form of iron in liver and macrophage
A. ferrous
B. ferritin
C. ferric
D. ferroportin
B
132
Which of the following best describes hepcidin?
A.Synthesized in the gallbladder
B. Degrades ferroportin
C. Completes with iron transporter
D. Oxidizes iron
B
133
Which of the ff. oxidized ferrous iron to ferric iron?
A. Duodenal cytochrome B reductase
B. Hephaestin
C. Ceruloplasmin
D. Hepcidin
C
134
Which of these is true about heme synthesis in mammalian cells?
A. Succinyl Coa & alanine are immediate substrate of formation of delta-aminolevulinic acid
B. Porphobilinogen is formed from the condensation of 2 molecules of delta-aminolevulinic acid
C. Ferric iron is inserted into protoporphyrin IX
D. Coproporphyrin IV is an intermediate
B
135
Which of the following is true regarding porphobilinogen synthase?
A. It is the control step in heme synthesis
B. It is inhibited by lead
C. It requires B6 phosphate for activity
D. It is mitochondrial enzyme
B
136
Which of the ff enzymes in heme synthesis is found in the cytoplasm?
A. Uroporphyrinogen decarboxylase
B. Protoporphyrinigen oxidase
C. Coproporphyrinogen oxidase
D. Ferrochelatase
A
137
An enzyme inhibitor is noted to result in accumulation of uroporphyrinogen and its derivatives. Toxic levels of these inhibitors will most likely result to, EXCEPT:
A. Pallor
B. Abdominal pain
C. Photosensitivity
D. Neuropsychiatric syndrome
A
If not except: C
138
Which of the following is produced by heme oxygenase
A. CO
B. O2
C. Fe2+
D. H20
A
139
A rise in serum "direct" bilirubin is involved in
A. Hemolytic jaundice
B. Biliary jaundice
C. Absence of glucuronyl transferase
D. Decrease of hepatic uptake of bilirubi
B
140
What is the predominant form of bilirubin seen in obstructive jaundice?
A. Bilirubin monoglucuronide
B. Bilirubin diglucuronide
C. Bilirubin triglucuronide
D. Delta bilirubin
B
141
Which of the following is added to bilirubin for it to become water-soluble?
A. Glucose
B. Glucuronate
C. Glycogen
D. UDP-glucose
B
142
The rate limiting step in bilirubin metabolism occurs in the hepatic:
A. Cytoplasmic membrane
B. Cytoplasm
C. Endoplasmic Reticulum
D. Canaliculi
A
143
The anticoagulant effect of aspirin is due to its ability to:
A. Inhibit von willebrand factor
B. Increase production of PGI2
C. Interfere with the activity of cyclooxygenase
D. All of the above
C
144
The major pathway for the synthesis of bile acids is via hydroxylation of cholesterol by
A. 7- a hydroxylase
B. 7-dehydrocholesterol reductase
C. Sterol 27-hydroxylase
D. Oxysterol 7- a hydroxylase
A
145
Which of the following is the rate-limiting enzyme in cholesterol synthesis?
A. Lipoprotein lipase
B. Lecithin cholesterol acetyl transferase
C. Hepatic lipase
D. HMG CoA reductase
D
146
Which of the following has an autosomal dominant inheritance?
A. Abetalipoproteinemia
B. Familial hypercholesterolemia
C. Tangier's disease
D. Apoprotein C-II deficiency
B
147
A patient demonstrated steatorrhea and a buildup of intestinal triglycerides. This observation is most likely due to deficiency in the production of which apoprotein?
A. Apo AI
B. Apo E
C. Apo B48
D. Apo B100
C
148
Which if the following is the function of apolipoprotein C II?
A. Lower serum cholesterol
B. Activate Lipoprotein lipase
C. Increase chylomicron production
D. Increase cholesterol uptake in liver cells
B
149
A young housewife has been diagnosed with Type I hyperlipidemia. Which of the following lipoproteins is elevated?
A. LDL
B. VLDL
C. IDL
D. Chylomicrons
D
150
The regulation of cholesterol synthesis primarily occurs in an enzymatic reaction involving beta-3hydroxy-3-methylglutarate CoA _____.
A. Synthase
B. Lyase
C. Reductase
D. Oxidase
C
151
In order for chylomicron remnant to be taken up by the liver, which apoprotein in the remnant must interact first with remnant receptor?
A. Apo A
B. Apo B48
C. Apo B100
D. Apo E
D
152
Site of re-synthesis of triglycerides following intestinal reabsorption:
A. Mitochondria
B. Lymphatic system
C. SER of gastric epithelium
D. SER of intestinal epithelial cells
D
153
Which enzymes of fatty acid synthesis participate in synthase activity?
A. Condensing enzymes & thioesterase
B. Ketoacyl synthase & ketoacyl reductase
C. Ketoacyl reductase & thioesterase
D. Enoyl reductase & ketoacyl reductase
B
154
In alpha-oxidation of fatty acids, which of the following products are released
A. CoA
B. CO2
C. H2O
D. Acetyl CoA
B
155
HMG-CoA is reduced to Mevalonate for the synthesis of cholesterol. The enzyme catalyzing this process is:
A. HMG-CoA reductase
B. HMG-CoA synthase
C. Thiolase
D. Thioesterase
A
156
What is the production of the reaction catalyzed by HMG-CoA reductase?
A. Squalene
B. Lanosterol
C. Cholesterol
D. Mevalonate
D
157
Glucagon and epinephrine stimulate glycogen breakdown to glucose-6-phosphate?
A. Directly by binding to glycogen phosphorylase
B. Indirectly by first stimulating adenylate cyclase to make cAMP
C. Only in the liver
D. Via calcium mediated mechanisms
B
158
The active form of glycogen phosphorylase is phosphorylated, while the dephosphorylation of which enzyme activates it
A. Glycogen synthase
B. Glycogen phosphorylase
C. Glycogen semisynthase
D. Glycogen dehydrogenase
A
159
Which of the following enzymes is involved in glycogenesis?
A. Oxidoreductase
B. Lyase
C. Isomerase
D. Hydrolase
C
160
Which of the following compounds is responsible for the coordinated regulation of gluconeogenesis and glycolysis?
A. NAD+
B. Acetyl CoA
C. Fructose-2,6-bisphosphate
D. NADH
C
161
Which of the following statements is FALSE about gluconeogenesis?
A. From hydrolysis of triacylglycerol, fatty acids can be used as carbon source
B. From breakdown of proteins, ketogenic amino acid must be converted to intermediates of the Kreb’s cycle
C. From vigorous muscle activity, lactate can be used as a carbon source
D. From red blood cells, lactate can be used as a carbon source
B
162
Glucose from the breakdown of glycogen is obtained from:
A. Liver by phosphorolysis
B. Muscle by phosphorylation
C. Muscle by hydrolysis
D. Liver and muscle
D
163
Which of the following enzyme catalyzes the conversion of pyruvate to oxaloacetate
A. Pyruvate Carboxylase
B. Pyruvate Dehydrogenase
C. Pyruvate Kinase
D. Phosphofructokinase-1
A
164
Gluconeogenesis involves conversion of
A. Glucose to pyruvate
B. Pyruvate to glucose
C. Phosphoenolpyruvate to fructose
D. Pyruvate to fructose
B
165
Which of the following processes is true about gluconeogenesis
A. Pyruvate is first converted to pep via pepck
B. Fructose-1,6-bphosphatase converts fructose-1,6-bphate
C. G-6-phosphatase hydrolyzes g-6-phosphate to glucose and is released into the blood
D. G-6-phosphatase hydrolyzes g
-6-phosphate to glucose and is found in liver and muscle
C
166
In the liver, what is considered as the most important activator of PFK-2 that controls the flux between the opposing pathways of glycolysis and gluconeogenesis?
A. Fructose-2,6-bisphosphate
B. Bisphosphoglycerate
C. Glucose-6-phosphate
D. Glyceraldehyde-3-phosphate
A
167
Which of the following is adversely affected when gluconeogenesis is impaired?
A. Liver
B. Muscles
C. Brain
D. Kidney
C
168
Which of the following is involved in pentose phosphate pathway?
A. Oxidoreductase
B. Lyase
C. Ligase
D. Hydrolase
A
169
The pentose phosphate pathway is also known as the hexose monophosphate shunt because.
A. glucose is used to generate non-glycolytic products but recovered later in the form of intermediates of the glycolytic pathway
B. intermediates of the glycolytic pathway are metabolized and recovered at the end
C. most phosphorylated hexoses are utilized in the pathway
D. glucose is broken down and recovered intact at the end of the pathway
A
170
What molecule is produced at the end of the 2nd phase of the pentose phosphate pathway
A. Water
B. Nitrogen
C. Carbon dioxide
D. Sugar
D
171
Which of the following pathways is affected if the second phase of the pentose phosphate pathway is impaired?
A. DNA synthesis
B. Lipid synthesis
C. RBC membrane integrity
D. Hepatic detoxification
A
172
Which if the following is a hydrophilic amino acid
A. Tyrosine
B. Tryptophan
C. Leucine
D. Lysine
D
173
Proteins under this classification have an axial ratio greater than 10 and usually serves as structural proteins:
A. Oligomeric
B. Globular
C. Fibrous
D. Quaternary
C
174
Which of the following is not true about protein denaturation?
A. It is the disruption of the conformation of protein
B. Reagents used for protein denaturation such as urea and sodium dodecyl sulfate target peptide bonds
C. Reagents used for protein denaturation disrupt the protein structure except for primary structure
D. AOTA
B
175
All of the following inactive protease is activated by trypsin, except:
A. Chymotrypsinogen
B. Pepsinogen
C. Procarboxypeptidase
D. Proaminopeptidase
B
176
Which amino acid is a major source of glucose carbon in gluconeogenesis?
A. Alanine
B. Glycine
C. Cysteine
D. Threonine
A
177
A defect in the gene that codes for the dibasic amino acid transport system can lead to:
A. Hartnup disease
B. Joseph syndrome
C. Cystinuria
D. Dicarbolxylic aminoaciduria
C
178
Which of the following is most likely consumed during the urea cycle?
A. Ornithine
B. Citruline
C. Asparagine
D. Aspartate
D
179
Which of the following are catabolized to pyruvate and acetyl CoA?
A. Leucine
B. Threonine
C. Tryptophan
D. Proline
B
180
Which of the following amino acids would have succinyl CoA as its product?
A. Leucine
B. Isoleucine
C. Valine
D. Phenylalanine
B, C
181
Which of the following can be inhibited by nicotinic acid derivatives?
A. Kynurenine formylase
B. Kynurenine decarboxylase
C. Kvnureninase
D. Tryptophan oxygenase
D
182
Correct sequence of the first three reactions involving the branched chain amino acids:
A. Transamination - conversion to coenzyme A thioesters - oxidative carboxylation
B. Conversion to coenzyme A thioesters - oxidative carboxylation - transamination
C. Oxidative carboxylation - transamination - conversion to coenzyme A
D. Transamination - oxidative carboxylation - conversion to coenzyme A
D
183
Hyperlysinemia is due to a defect in
A. Reduction of aminoadipate delta-semialdehyde
B. Transamination to a-ketoadipate
C. Activity of the bifunctional enzyme
D. Decarboxylation of glutaryl coA to crotonyl coA
C
184
Which of the following is correct about transamination?
A. It liberates all ammonia from the amino acid
B. Almost all amino acid catabolism is initiated by transamination
C. It is preceded by oxidative deamination
D. The coenzyme in amino acid is pyridoxal phosphate
C
185
Which of the following would result in a positive nitrogen balance?
A. 80 y/o old man brisk walk
B. Pregnant 30 weeks AOG
C. Beggar who hasn't eaten for days
D. Who had surgery sa abdomen
B
186
Which of the following molecules are oxaloacetate’s source of carbon?
A. Acetyl coa, aspartate
B. Arginine, aspartate
C. Arginine, acetyl coa
D. Acetyl coa, asparagine
A
187
Which vitamin play a role in lipogenesis
A. Biotin
B. Folic acid
C. Pantothenic acid
D. Thiamin
C
188
Water-soluble vitamins are once thought to be safe and do not cause any toxicity. Recent studies have shown that this vitamin is associated with increased risk of developing colorectal cancer in patients who have preneoplastic colorectal polyps:
A. Folic acid
B. Nicotinic acid
C. Ascorbic acid
D. Pantothenic acid
A
189
What are the possible conditions when direct latching is not possible?
A. Mother is sick and undergoing surgery
B. Baby is taking antibiotics and undergoing surgery
C. Both A and B
D. None of the above
C
190
Maritess is 16 years old. She wanted to gain weight for her graduation ball. She weighs 60 kg and had a height of 5’9”, What is her DBW?
A. 67
B. 68
C. 69
D. 70
B
191
If her PA is 50%, what is her SDA?
A. 244
B. 245
C. 246
D. 244.8
D
192
What is her TER?
A. 2,699
B. 2,690
C. 2,700
D. 2,800
C
193
What is Maritess’ dietary prescription?
A. 2600 cal - 335g - 110g - 100g
B. 2600 cal - 330g - 105g - 100g
C. 2700 cal - 340g - 110g - 105g
D. 2700 cal - 340g - 100g - 105g
D
194
Maritess eat two cups of cooked rice per meal. She decided to replace rice for breakfast with two exchanges of sliced bread. How much less calories are these for her breakfast?
A. 200
B. 300
C. 400
D. 500
A
195
Enzyme X in a normal saline solution containing molybdenum catalyzed the formation of product P from substrate S at a rate of 90 U/min. The same enzyme X placed in normal saline solution only resulted in the formation of product P at a rate of 2 U/min. Enzyme X is most likely
a. Requires molybdenum as coenzyme
b. A metal-activated enzyme
c. As competitively inhibited by normal saline
d. Is a metalloenzyme
B
196
Which of the following statement is correct about iron metabolism
a. All iron absorbed in the intestine are stored as ferritin
b. Ferrireductase acts on heme iron before it enters the cytoplasm
c. The transporter across the enterocyte are specific only to iron
d. The transporter at the basolateral portion of the enterocyte are ferroportin
D
