Quiz
Biochemistry Exam 5- 2nd Year-2nd Semester- PMU
Create a free account to finish this quiz
Save your progress and see your final score.
Already have an account? Sign in
Questions in this quiz (45)
1Which of the following is true?
- ATransaminases are specific for only one pair of α-amino and α-keto acids
- BTransaminases co-work with Vitamin B1 (thiamine pyrophosphate) as coenzyme
- CTransaminases co-work with Vitamin B6 (pyridoxal phosphate) as coenzyme
- DTransaminases fix ammonia as amino group in amino acids
- ETransaminases release free ammonia from α-amino acids
2Which of the following a-amino acids is essential?
- AGlycine
- BGlutamate
- CSerine
- DValine
- ELysine
3Which of the following α-amino acids are glycogenic?
- ALysine, Cysteine and Proline
- BGlycine, Alanine and Proline
- CLeucine, lsoleucine and Valine
- DAspartate, Glutamate and Serine
- ELeucine, Phenylalanine and Tyrosine
4Which of the following α-amino acids is ketogenic?
- AGlycine
- BLeucine
- Clsoleucine
- DValine
- EAlanine
5Which of the following mechanisms play role in ammonia detoxification:
- AGlutamine biosynthesis in brain
- BUrea biosynthesis in muscles
- CAlanine biosynthesis in muscles
- DUrea biosynthesis in liver
- ENH4+ formation in kidney
6Which of the following statements about glutamate dehydrogenase are true:
- Athe enzyme is regulated
- Bthe enzyme is associated with the respiratory chain and the formation of energy
- Cthe enzyme uses FAD as cofactor
- Dthe enzyme uses NAD+ as cofactor
7Which of the following statements about the urea cycle are true
- Aurea catabolizes in urea cycle
- Bit does not use cell energy
- Cit has mitochondrial and cytosol phase
- Din urea cycle a toxic product is converted into less toxic product which is excreted
8Which of the following is involved in purine ring formation?
- AAlanine
- BAspartate
- CGlutamate
- DCarbamoyl phosphate
- EGlycine
9Which of the following is involved in pyrimidine ring formation?
- AAlanine
- BAspartate
- CGlutamate
- DCarbamoyl phosphate
- EGlycine
10Which of the following about GOUT is TRUE:
- Ait is characterised by elevated concentration of uric acid in blood
- Bit may be due to overproduction of purine nucleotides or decreased renal excretion of uric acid
- Cmany of the clinical symptoms arise because of the high solubility of uric acid in the aqueous environment
- Dallopurinol is used for the treatment of gout since it inhibits xanthine oxidase
11Which are the end products from pyrimidine degradation
- Auric acid
- Bβ-aminoisobutyrate
- Curea
- Dβ-alanine
- ENH3 and CO2
12Porphyrin biosynthesis occurs in:
- Acytosol
- Bmitochondria
- Cboth cytosol and mitochondria
- Dcytosol, mitochondria and cell nucleus
- Eendoplasmic reticulum
13Which of the following is correct?
- Aheme is synthesized from succinyl-CoA and glycine
- Bheme is synthesized from aspartate and carbamoyl phosphate
- Cheme is an example of iron porphyrins
- Dheme is an example of magnesium porphyrins
- Ethe clinical condition jaundice is due to elevation of bilirubin in blood plasma
14Which of the following is TRUE:
- Ain prehepatic jaundice only the direct bilirubin is increased in serum
- Bin hepatic jaundice only the indirect bilirubin is increased in serum
- Cin posthepatic (obstructive) jaundice urine urobilinogen is absent
- Dthe neonatal physiologic jaundice results from an accelerated hemolysis around the time of birth and an immature hepatic system for the uptake, conjugation and excretion of bilirubin
- EGilbert Syndrome is caused by deficiency in biliverdin reductase
15Which of the following is true?
- ACarbamoyl phosphate synthetase 1 uses glutamine for the synthesis of urea
- BNH3 may be toxic to the brain because ammonia reacts with α-ketoglutarate to form glutamate and this results in depletion of the levels of α-ketoglutarate which impairs the function of the TCA cycle in neurons
- Cclinical symptoms of ammonia intoxication include tremor, slurred speech, blurred vision, coma and ultimately death
- Da high protein diet and starvation result in induction of urea cycle enzymes
16Which of the following human proteins contain porphyrins:
- AMyoglobin
- BCyt. P450
- CCyt. C1
- DCatalase
- EFerritin
17Which of the following is NOT TRUE
- AThymidylate synthase catalyzes the synthesis of dTMP
- BH4 folate derivatives serve as one carbon donor for purine biosynthesis de novo
- Cribonucleotide reductase plays important role in RNA synthesis
- DCTP is produced by amination of UTP by CTP synthetase
18Which of the following amino acids may undergo oxidative deamination followed by energy production:
- AGlycine
- BTrytophan
- CLysine
- DGlutamate
- ECytesine
19Which of the statements about aminotransferases are TRUE
- Athey use thiamine diphosphate as a coenzyme
- Bthey use pyridoxal phosphate as a coenzyme
- Cthe ALAT content increases in cardiac infarction
- Dthe ASAT and ALAT content increases in liver disease (e.g: hepatitis)
20Which of the following compounds can accept NH2-group in transamination
- Apyruvate
- Bacetone
- Cα-ketoglutarate
- Dacetoacetate
- Eoxaloacetate
21Which of the following biogenicamines are neurotransmitters
- Aγ-aminobutyrate (GABA)
- Bserotonin
- Ctyrosine
- Ddopamine
- Eadrenaline
22Which of the following amino acids can not undergo transamination
- Alysine
- Bproline
- Calanine
- Dglutamate
- Ethreonine
23Which of the statements about aminotransferase are TRUE
- Athey use NAD + as a coenzyme
- Bthey use pyridoxal phosphate as a coenzyme
- Cthe ASAT content increases in cardiac infarction
- Dthe ASAT and ALAT content decreases in liver disease (e.g hepatitis)
24Which of the following is TRUE
- Aarginine and glycine are used for the biosynthesis of creatine
- Bcreatine phospate serves a storage form of energy in muscles, heart and brain
- Ccreatine kinase catalyses the reaction creatine phosphate -> creatinine
- Dwhen ATP is utilized as a source of energy for muscular contraction creatine phosphate maintains its concentration
25Which of the following compounds are neurotransmitters
- Aserine
- Bglycine
- Cserotonin
- Ddopamine
- Eacetylcholine
26Which of the following compounds are amino group acceptors in transaminase reactions?
- Aα-ketoglutarate
- Bacetone
- Coxaloacetate
- Dpyruvate
- Eglutamate
27Which are the end products of N-metabolism?
- ACreatine
- BCreatinine
- CUrea
- DAmmonia
- EAmmonium cations
- FUric acids
28Which of the following statements about pyrimidine synthesis are TRUE:
- APyrimidine ring is formed by adding atoms to PRPP
- BPRPP is added to the already formed pyrimidine ring
- CDerivatives of tetrahydrofolate (THF) are necessary for TMP production
- DSAM is necessary for TMP production
29What is the origin of the atoms for "de novo" purine synthesis?
- AN7, C8 and N9 from glycine
- BC4, C5 and N7 from glycine
- CC6 from CO2
- DC8 from CO2
30Which of the following statements about iron metabolism are FALSE:
- Ahemosiderin is the major iron-storage protein
- Bferritin is the major iron-storage protein
- Ctransrefin can bind only ferrous cations ( Fe3+)
- Dtransrefin can bind only ferrous cations ( Fe2+)
- Ethe major regulator of piasma iron concentration is the humoral factor hepcidin
31Which of the following compounds participate in both Krebs cycle and in transaminase reactions?
- Aoxaloacetate
- Bacetoacetate
- Cα-ketoglutarate
- Dpyruvate
- Eisocitrate
- Fmalate
32N-atom in carbamoyl phosphate, used for pyrimidine ring synthesis, derives from
- AAmmonia (NH3)
- BAspartate
- CGlutamate
- DGlutamine
- EGlycine
33Which of the following reactions from urea cycle demand ATP?
- AArginine -> Ornithine + Urea
- BOrnithine + Carbamoyl phosphate -> Citrulline
- CNH3 + CO2 -> Carbamoyl phosphate
- DCitrulline + Aspartate -> Arginosuccinate
- EArgininosuccinate -> Arginine + Fumarate
34Which of the following statements about phenylalanine degradation are TRUE?
- Aphenylalanine is hydroxylated to tyrosine
- Bphenylalanine hydroxylases uses NADPH + H+ as a cofactor
- Ca deficiency of homogentisate oxidase cause tyrosinemia type 2
- Da deficiency of phenyalanine hydroxylase results in higher concentration of phenylpyruvate, phenylpyruvate, phenyllactate and phenylacetate
- Ephenylalanine hydroxylase uses ascorbic acid as a cofactor
35Which of the following statements about "de novo“ purine synthesis are TRUE?
- APurine ring formed by adding atoms to PRPP
- BPRPP to the already formed purine ring
- CDerivatives Of tetrahydrofolate (THF) are necessary for purine synthesis
- DSAM is necessary for purine synthesis
36What of the following statements about iron metabolism are FALSE?
- Ahephaestin and ceruloplasmln are both ferrireductases, but with different localization
- Bhepcidin decreases serum iron by blocking ferroportin (IREG1)
- Cthe major iron depot is the hemosiderin in liver
- Dtransferrin is a non-heme iron-transport protein
37Which of the following statements are TRUE?
- Anormally urine does not contain urobilinogen
- Bheme oxygenase requires NADH+H+ as a cofactor
- Cin prehepatic jaundice (hemolytic anemia) there is an increase of urine urobilinogen
- Dhepatic (parenchymal) jaundice is characterized by increase only of indirect bilirubin
- Eposthepatic (obstructive) jaundice is characterized by an increase in direct bilirubin and pale feces
38Which of the following amino acids are essential and glucogenic?
- Amethionine
- Bcysteine
- Cphenylalanine
- Dvaline
- Ethreonine
- Ftryptophan
39Which of the following biologically active compounds DO NOT derive from tyrosine?
- ADopamine
- BMelanin
- CMelatonin
- DGABA
- EEpinephrine
40Which of the following statements about heme (haem) synthesis are TRUE:
- Ait is located in the mitochondria
- Bit is located in both the mitochondria and the cytosol
- Cthe main regulatory enzyme is ALA synthase
- Dthe main regulatory enzyme is ALA dehydratase
- Eporphyrias can be caused by a deficiency in ALA syntahse
- Fheme is the major allosteric inhibitor and gene suppresor synthesis
41Which of the listed biologically active compounds derive from essential and semi-essential amino acids?
- ANO
- BGABA
- CHistamine
- DMelanin
- EThyroid hormones
- FMelatonin
42Which of the following statements about purines are FALSE:
- AThe major regulatory enzyme of "de novo" purine synthesis is ALA synthetase
- BThe major regulatory enzyme of ”de novo” purine synthesis is Glutamine-PRPP amidotransferase
- CThere is a cross regulation between adenosine and guanosine nucleotides production
- DPRPP is the major allosteric inhibitor of ”de novo” purine synthesis
- EGout can be caused by decreased activity of PRPP synthetase and increased activity of hypoxanthine-guanine phosphoribosyltransferase (HPGT)
43Which of the following statements are TRUE
- Anormally urine does not contain bilirubin
- Bbilverdin reductase converts the green pigment biliverdin into direct bilirubin using NADPH + H+ as a cofactor
- Cin prehepatic jaundice (hemolytic) there are only traces of urobililinogen in urine
- Dhepatic (parenchymal) jaundice is characterized by an increase in urine urobilinogen
- Eposthepatic (obstructive) jaundice is characterized by an increase in direct bilirubin and dark feces
- Fbilirubin-UDP glucuronosyltransferase is deficient in Gilbert's syndrome
44Which of the following is TRUE
- Acarbamoyl phosphate synthetase 1 is a cytosolic enzyme
- Bcarbamoyl phosphate synthetase 1 is a mitochondrial enzyme
- Ccarbamoyl phosphate synthetase 1 uses glutamine as nitrogen donor
- Dcarbamoyl phosphate synthetase 1 is activated by N-acetyl glutamate
45Which of the following human proteins contain porphyrins
- Athe respiaratory chain cytochromes
- Bcyt P450
- Chemoglobin
- Dcatalase
- Ealbumin
Information
- Description
- Biochemistry Exam 5- 2nd Year- PMU
- Author
- Med Student
- Language
- English
- Views
- 1,001
- Tags
- Rating
- No ratings yet Rate this quiz