Final Exam - Exam 3 Review Flashcards by Judah Abernathy

Which of the following statements about Purine and Pyrimidine biosynthesis and metabolism is correct (or True)? (Select all that apply)

A: Antifolate drugs and Glutamine analogs block purine nucleotide biosynthesis.
B: PRPP (phosphoribosylpyrophosphate) synthase phosphorylates the anomeric OH group of Ribose 5’-phosphate.
C: cAMP and cGMP feedback regulate their formation from IMP (InosineMonophosphate).
D: Orotic aciduria is a consequence of the inability of severely damaged mitochondria to utilize carbamoyl phosphate.

A: Antifolate drugs and Glutamine analogs block purine nucleotide biosynthesis.
B: PRPP (phosphoribosylpyrophosphate) synthase phosphorylates the anomeric OH group of Ribose 5’-phosphate.
D: Orotic aciduria is a consequence of the inability of severely damaged mitochondria to utilize carbamoyl phosphate.

How well did you know this?

Not at all

Perfectly

Which of the following statements is incorrect (or False)?

A: Thyroid hormones are transported by thyroid binding globulin.
B: Glucocorticoids are transported by corticosteroid binding globulin.
C: Group I hormones are lipophilic.
D: Group II hormones have a long plasma half-life.

D: Group II hormones have a long plasma half-life.

How well did you know this?

Not at all

Perfectly

Which of the following are hormones that bind to cell surface receptors? (Select all that apply)

A: Angiotensin II
B: Glucagon
C: PTH
D: ACTH

How well did you know this?

Not at all

Perfectly

Which of the following hormones bind to intracellular receptors? (Select all that apply)

A: Glucocorticoids
B: Insulin
C: Mineralcorticoids
D: Glucagon

A: Glucocorticoids
C: Mineralcorticoids

How well did you know this?

Not at all

Perfectly

Which of the following statements about Pyrimidine metabolism is correct (or True)? (Select all that apply)

A: Primary amine group in Cytosine is first oxidized to the oxo group to form (or synthesize) dihydrouracil
B: Primary amine group in Cytosine is first oxidized to the oxo group to form (or synthesize) Uracil.
C: The final metabolic product of cytosine metabolism is beta alanine
D: The final metabolic product of Thymine is beta-aminoisobutyrate.

B: Primary amine group in Cytosine is first oxidized to the oxo group to form (or synthesize) Uracil.
C: The final metabolic product of cytosine metabolism is beta alanine
D: The final metabolic product of Thymine is beta-aminoisobutyrate.

How well did you know this?

Not at all

Perfectly

Which of the following statements about purine metabolism is correct (or True)? (Select all that apply)

A: Adenosine deaminase oxidizes the primary amine in adenine to an oxo group.
B: Purine nucleoside phosphorylase hydrolyzes the beta N glycosidic bond to form hypoxanthine.
C: Xanthine is reduced to Uric acid.
D: Hypoxanthine is oxidized to Xanthine.

A: Adenosine deaminase oxidizes the primary amine in adenine to an oxo group.
B: Purine nucleoside phosphorylase hydrolyzes the beta N glycosidic bond to form hypoxanthine.
D: Hypoxanthine is oxidized to Xanthine.

How well did you know this?

Not at all

Perfectly

Which of the following disorders of purine catabolism is correct (or True)? (Select all that apply)

A: Lesch-Nyhan syndrome represents overproduction of hyperuricemia which is characterized by frequent episodes of self mutilation.
B: Purine overproduction and hyperuricemia is found in Von Gierke disease.
C: Hypouricemia and increased excretion of hypoxanthine and xanthine are associated with a deficiency in xanthine oxidase.
D: Adeosine deaminase deficiency is associated with an immunodeficiency disease.

How well did you know this?

Not at all

Perfectly

Xeroderma pigmentosum (XP) is an inherited defect that is related to inability to remove which of the following?

A: TT dimer
B: AT dimer
C: GC dimer
D: AA dimer

A: TT dimer

How well did you know this?

Not at all

Perfectly

Which of the following enzymes will cleave the heterocyclic base from the sugar?

A: DNA ligase
B: Exonuclease
C: Beta N-glycosidase
D: Endonuclease

C: Beta N-glycosidase

How well did you know this?

Not at all

Perfectly

Which of the following statements about the formation of the peptidyl bond in protein formation is True (or Correct)?

A: The alpha amino group of the incoming amino acid at the “A” site carries out a nucleophilic attack on the amide group of the peptidy-tRNA at the “P” site.
B: The alpha amino group of the incoming amino acid at the “A” site carries out a nucleophilic attack on the ester group of the peptidy-tRNA at the “P” site.
C: The alpha carboxyl group of the incoming amino acid at the “A” site carries out a nucleophilic attack on the amide group of the peptidy-tRNA at the “P” site.
D: The alpha carboxyl group of the incoming amino acid at the “A” site carries out a nucleophilic attack on the ester group of the peptidy-tRNA at the “P” site.

B: The alpha amino group of the incoming amino acid at the “A” site carries out a nucleophilic attack on the ester group of the peptidy-tRNA at the “P” site.

How well did you know this?

Not at all

Perfectly

In DNA replication process, the key step in opening up the superstructure is acetylation of an amino acid residue in histones. Which of the following amino acids is acetylated?

A: Lysine
B: Asparagine
C: Glycine
D: Glutamine

A: Lysine

How well did you know this?

Not at all

Perfectly

The mature m-RNA is capped by which of the following heterocyclic bases (or which of the following heterocyclic bases are present on the cap of a mature m-RNA?

A: 5-methyguanine triphosphate B: 7-methylcytosine triphosphate
C: 7-methylguanine triphosphate
D: 5-methylcytosine triphosphate

C: 7-methylguanine triphosphate

How well did you know this?

Not at all

Perfectly

Which of the following types is a description of Two base alteration of DNA?

A: Depurination
B: UV light induced Pyrimidine dimer
C: Ionizing radiation
D: Deamination of Cytosine to Uracil.

B: UV light induced Pyrimidine dimer

How well did you know this?

Not at all

Perfectly

Which of the following arms of t-RNA is required for recognition of the t-RNA by its proper aminoacyl t-RNA synthetase?

A: D arm
B: T(psi)C arm
C: Acceptor arm
D: Anti-codon arm

A: D arm

How well did you know this?

Not at all

Perfectly

Which of the following reactions listed against each enzyme is incorrect (or False)?

A: DNA ligase catalyzes bonds between DNA molecules
B: Exonuclease III removes nucleotides from the 3’ ends of DNA
C: S1 nuclease degrades double stranded DNA
D: Lambda Exonuclease removes nucleotides from the 5’ ends of DNA

C: S1 nuclease degrades double stranded DNA

How well did you know this?

Not at all

Perfectly

In DNA replication process, the phosphodiester bonds are formed between which two carbons of the adjacent ribose sugars?

A: 3’ and 5’
B: 3’ and 4’
C: 3’ and 2’
D: 3’ and 1’

A: 3’ and 5’

How well did you know this?

Not at all

Perfectly

Which of the following motifs does not exist as dimers?

A: Leucine zipper
B: Helix-turn-helix
C: Zinc finger
D: Thymine-Thymine dimer

C: Zinc finger

How well did you know this?

Not at all

Perfectly

In DNA replication process, which of the following enzymes initiates nicks on one strand to remove supercoils and super twists?

A: DNA topoisomerase I
B: DNA toposiomerase II
C: DNA gyrase
D: Helicase

A: DNA topoisomerase I

How well did you know this?

Not at all

Perfectly

In translation of an mRNA into a protein, the first amino acid that is attached to the start codon is which of the following?

A: Cysteine
B: O-formylmethionine
C: N-formylmethione
D: Serine

C: N-formylmethione

How well did you know this?

Not at all

Perfectly

Which of the following is the action of SnRNA (slurps)?

A: Important in growth and development
B: Knocks out a portion of the gene
C: Splices the introns out of m-RNA
D: Splices out the exons out of m-RNA

C: Splices the introns out of m-RNA

How well did you know this?

Not at all

Perfectly

Pol II is active when its tail is phosphorylated. Which of the following amino acids is present in the tail that gets phosphorylated?

A: Serine
B: Cysteine
C: Tyrosine
D: Tryptophan

A: Serine

How well did you know this?

Not at all

Perfectly

Which of the following descriptions refer to the Leucine Zipper Motif?

A: Consists of three antiparallel beta sheets and three alpha helices.
B: Consists of closely spaced Cysteine-Cysteine residues followed by 12 to 13 amino acids later by histidine- histidine pair.
C: Consists of a beta sheet in which there is a periodic repeat of leucine residues at every 7th position.
D: Consists of an alpha helix in which there is a periodic repeat of leucine residues at every 7th position.

D: Consists of an alpha helix in which there is a periodic repeat of leucine residues at every 7th position.

How well did you know this?

Not at all

Perfectly

Which of the following is an example of an unacceptable missense?

A: Hb A, is converted to Hb M (Boston) where the alpha chain Histidine at #58 is replaced by Tyrosine.
B: HbA is converted to Hb Hikari, where the beta chain Lysine at #61 is replaced by Asparagine.
C: Hb A is converted to Hb S, where the beta chain Glutamate at #6 is replaced by Valine.

A: Hb A, is converted to Hb M (Boston) where the alpha chain Histidine at #58 is replaced by Tyrosine.

How well did you know this?

Not at all

Perfectly

Which of the following statements is incorrect (or False)?

A: The lagging strand is replicated discontinuously in short pieces of 100-250 nucleotides by DNA polymerase in the 3’ to 5’ direction.
B: The DNA replication is initiated at special sites termed Ori’s to generate replication bubbles.
C: Each strand of the double helix is replicated simultaneously by by somewhat different mechanism.
D: A complex of proteins, including DNA polymerase, replicates the leading strand continuously in the 5’ to 3’ direction.

A: The lagging strand is replicated discontinuously in short pieces of 100-250 nucleotides by DNA polymerase in the 3’ to 5’ direction.

How well did you know this?

Not at all

Perfectly

Which of the following statements about AcetylCholine (ACh) is correct (or True)? (Select all that apply) A: Two molecules of ACh bind to the alpha subunits of the heteropentameric receptor (AChR). B: ACh is removed from the receptor by the enzyme acetylcholinesterase. C: When ACh binds to the ACh receptor, it opens up the ion channel where Na+ ions flow in and K+ ions flow out. D: ACh is inhibited reversibly by Phosphonates in nerve gas and some pesticides.

A: Two molecules of ACh bind to the alpha subunits of the heteropentameric receptor (AChR). B: ACh is removed from the receptor by the enzyme acetylcholinesterase. C: When ACh binds to the ACh receptor, it opens up the ion channel where Na+ ions flow in and K+ ions flow out.

Which of the following statements about hormones and neurotransmitters is correct (or True)? (Select all that apply) A: The excitatory neurotransmitters are Glutamate, aspartic acid and cysteine. B: The inhibitory neurotransmitters are glycine, taurine, beta alanine and Gamma aminobutyric acid. C: To stop the action of Catechol amines, Monoamine Oxidases (MAOs) reduce the amine (or quarternary amine) group to to the corresponding aldehyde group. D: Methionine encephalin is a pentapeptide that is present in certain nerve terminals that bind to specific pain receptors.

A: The excitatory neurotransmitters are Glutamate, aspartic acid and cysteine. B: The inhibitory neurotransmitters are glycine, taurine, beta alanine and Gamma aminobutyric acid. C: To stop the action of Catechol amines, Monoamine Oxidases (MAOs) reduce the amine (or quarternary amine) group to to the corresponding aldehyde group.

Which of the following statements about GPCR is correct (or True)? (Select all that apply) A: G-proteins associated with GPCR are heterotrimeric where the gamma subunit is attached to the plasma membrane by an isoprenoid tail. B: The alpha subunit, formed after activation, also has an intrinsic hydroylase (or GTPase) activity. C: GPCR is a seven transmembrane receptor with the N-terminal on the outside of the cell and the C terminal on the inside of the cell. D: Many of the Group I hormones bind to receptors that couple to effectors through a G protein.

A: G-proteins associated with GPCR are heterotrimeric where the gamma subunit is attached to the plasma membrane by an isoprenoid tail. B: The alpha subunit, formed after activation, also has an intrinsic hydroylase (or GTPase) activity. C: GPCR is a seven transmembrane receptor with the N-terminal on the outside of the cell and the C terminal on the inside of the cell.

Which of the following statements about hormones is correct (or True)? (Select all that apply) A: Diacylglycerol (DAG) is capable of activating Protein Kinase C (PKC). B: cAMP dependent protein kinase A (PKA) phosphorylates Glycogen synthase a (active) into glycogen synthase b (inactive). C: Protein kinase G (PKG) phosphorylates several smooth muscle proteins. D: Pyruvate kinase, pyruvate carboxylase, glycogen synthase enzymes are regulated by Ca+2 and or phosphorylation.

A: Diacylglycerol (DAG) is capable of activating Protein Kinase C (PKC). B: cAMP dependent protein kinase A (PKA) phosphorylates Glycogen synthase a (active) into glycogen synthase b (inactive). C: Protein kinase G (PKG) phosphorylates several smooth muscle proteins. D: Pyruvate kinase, pyruvate carboxylase, glycogen synthase enzymes are regulated by Ca+2 and or phosphorylation.

Which of the following statements about hormone action and signal transduction is correct (or True)? (Select all that apply) A: Excessive, deficient, or inappropriate production and release of hormones and other regulatory molecules are major causes of disease. B: Glucocorticoids diffuse through the plasma membrane and bind to the receptor in the cytoplasm before binding to the GRE on DNA, which has no corepressor attached to the GRE. C: Thyroid hormones enter the nucleus and bind to its hormone response element but fails to activate transcription because it exists in complex with a corepressor. D: Water soluble hormones have a transport protein that help them initiate a response by binding to the cell surface receptor.

A: Excessive, deficient, or inappropriate production and release of hormones and other regulatory molecules are major causes of disease. B: Glucocorticoids diffuse through the plasma membrane and bind to the receptor in the cytoplasm before binding to the GRE on DNA, which has no corepressor attached to the GRE. C: Thyroid hormones enter the nucleus and bind to its hormone response element but fails to activate transcription because it exists in complex with a corepressor.

The incorporation of fatty acid into lecithin occurs in three ways. Which one of the following is not one of the ways? (Select all that apply) A: By complete synthesis of the phospholipid. B: By transacylation between cholesteryl ester and lysolecithin C: By direct acylation of lysolecithin by acyl-CoA. D: By phosphorylation of lysolecithin.

D: By phosphorylation of lysolecithin.

Which of the following statement is correct (or True)? (Select all that apply) A: small ncRNA termed miRNA and siRNA typically inhibit gene expression B: The D-arm or D-loop contains pseudo uridine. C: snRNA are significantly involved in rRNA and mRNA processing and gene regulation. D: The acceptor arm in tRNA terminates in the nucleotides CCA.

A: small ncRNA termed miRNA and siRNA typically inhibit gene expression C: snRNA are significantly involved in rRNA and mRNA processing and gene regulation. D: The acceptor arm in tRNA terminates in the nucleotides CCA.

Which of the following statements is correct (or True)? (Select all that apply) A: When proteins bind to nucleotides they usually do not disrupt the base pairing between the DNA molecules. B: Endonucleases cleave internal phosphodiester bonds. C: The cap on the 5' terminal end of mRNA helps prevent attacks by 3' exonucleases. D: The 3' end of tRNA carries the amino acid for protein synthesis.

A: When proteins bind to nucleotides they usually do not disrupt the base pairing between the DNA molecules. B: Endonucleases cleave internal phosphodiester bonds. D: The 3' end of tRNA carries the amino acid for protein synthesis.

What types of lipids are involved in Multiple sclerosis and Lipidosis? (Select all that apply) A: Phospholipids B: Spingolipids C: Glycerolipids D: Glycolipids

A: Phospholipids | B: Spingolipids

Which two molecules begin the acylglycerol biosynthesis of triacylglycerols and phosphoglycerols? (Select all that apply) A: Glycerol-3-phosphate and dihydroxyacetone phosphate. B: Plasmalogen and Platelet activation factors. C: Phosphotidate and diacylglycerol D: Cardiolipin and Phosphatidylinositol

A: Glycerol-3-phosphate and dihydroxyacetone phosphate.

Which of the following statements about hormones and neurotransmitters is correct (True)? (Select all that apply) A: Adrenergic catecholamines, Adrenocorticotropic hormones, glucagon, parathyroid hormones all use cAMP as secondary messenger. B: Atrial natriuretic factor and nitric oxide use cGMP as secondary messenger. C: Angiotension II, Oxytocin uses Ca+2 or PI as secondary messenger. D: Polypeptides, proteins, glycoproteins and catecholamines are considered as Group I hormones.

A: Adrenergic catecholamines, Adrenocorticotropic hormones, glucagon, parathyroid hormones all use cAMP as secondary messenger. B: Atrial natriuretic factor and nitric oxide use cGMP as secondary messenger. C: Angiotension II, Oxytocin uses Ca+2 or PI as secondary messenger.

Which of the following statements about biosynthesis of nutritionally nonessential amino acids is correct (or True)? (Select all that apply) A: Glutamine is formed from glutamate by amidation reaction, using the ammonium ion. B: Transamination of pyruvate forms alanine and transamination of oxaloacetate forms aspartate. C: Aspartate is converted to Asparagine using the ammonium ion provided by Glutamine. D: Phenylalanine hydroxylase converts Tyrosine into Phenylalanine

A: Glutamine is formed from glutamate by amidation reaction, using the ammonium ion. B: Transamination of pyruvate forms alanine and transamination of oxaloacetate forms aspartate. C: Aspartate is converted to Asparagine using the ammonium ion provided by Glutamine.

Which of the following statements about the urea cycle is correct (or True)? (Select all that apply) A: Urea cycle disorders are characterized by hyperammonemia, encephalopathy, and respiratory alkalosis. B: Four of the five metabolic diseases result in accumulation of precursors of urea, principally ammonia and glutamine. C: Carbamoyl phosphate synthase I initiates urea biosynthesis. D: Cleavage of Arginine releases urea and re-forms Citrulline.

A: Urea cycle disorders are characterized by hyperammonemia, encephalopathy, and respiratory alkalosis. B: Four of the five metabolic diseases result in accumulation of precursors of urea, principally ammonia and glutamine. C: Carbamoyl phosphate synthase I initiates urea biosynthesis.

Which of the following statement about protein catabolism is correct (or True)? (Select all that apply) A: Glutamine or Glutamate is converted into alpha ketoglutarate by transamination. B: Tyrosine or phenylalanine is converted into Fumarate by a series of reactions. C: Asparagine or aspartate is converted into Oxaloacetate D: Alanine is converted into AcetoacetylCoA

A: Glutamine or Glutamate is converted into alpha ketoglutarate by transamination. B: Tyrosine or phenylalanine is converted into Fumarate by a series of reactions. C: Asparagine or aspartate is converted into Oxaloacetate

Which of the following is true of Angiotensin derivatives? (Select all that apply) A: Angiotensinogen is a large alpha2 globulin made in the liver. B: Angiotensinogen is converted into Angiotensin using Renin which is produced in the juxtaglomerular cells of the renal afferent arteriole. C: Angiotensin converting enzyme is a glycoprotein that converts Angiotensin I into Angiotensin II by removing two N-terminal amino acids. D: Angiotensins II and Angiotensin III are rapidly inactivated by angiotensinases.

A: Angiotensinogen is a large alpha2 globulin made in the liver. B: Angiotensinogen is converted into Angiotensin using Renin which is produced in the juxtaglomerular cells of the renal afferent arteriole. D: Angiotensins II and Angiotensin III are rapidly inactivated by angiotensinases.

Which of the following statements about Thyroxine and Triidothyronine is correct (or true). (Select all that apply) A: Thyroglobin is the precursor of T3 and T4. B: They are stored in an intracellular reservoir (as colloid) C: There is a peripheral conversion of T3 to T4 D: T3 is the more active form.

A: Thyroglobin is the precursor of T3 and T4. B: They are stored in an intracellular reservoir (as colloid) D: T3 is the more active form.

Which of the following statements is correct (or True)? (Select all that apply) A: Catecholamines are synthesized in final form and stored in secretion granules. B: Tyrosine hydroxylase is rate limiting for catecholamines. C: DOPA decarboxylase is present in all tissues. D: Phenylethanolamine-N-methyl (PNMT) catalyzes the production of Norepinephrine.

A: Catecholamines are synthesized in final form and stored in secretion granules. B: Tyrosine hydroxylase is rate limiting for catecholamines. C: DOPA decarboxylase is present in all tissues.

Which of the following statements is correct (or True)? (Select all that apply) A: Oxidation of the side chain of cholesterol by CYP450scc results in the formation of progesterone. B: Pregnenolone is converted to Dehydroepideandrosterone using 17 alpha hydroxylase and 17,20 lyase. C: Corticosterone is converted into Aldosterone by oxidation of the C18 methyl group. D: Androstenedione which is formed from dehydroepiandrosterone, has an alpha beta unsaturated ketone in the A ring.

B: Pregnenolone is converted to Dehydroepideandrosterone using 17 alpha hydroxylase and 17,20 lyase. C: Corticosterone is converted into Aldosterone by oxidation of the C18 methyl group. D: Androstenedione which is formed from dehydroepiandrosterone, has an alpha beta unsaturated ketone in the A ring.

Of the receptors listed below, which can conduct a flow of ions across the plasma membrane when bound to their cognate ligand? A: Receptor Tyrosine kinase (RTKs) B: G-protein coupled receptors (GPCR) C: Steroid hormone receptors D: Ligand gated channels

D: Ligand gated channels

Which of the following statements is correct (or True)? (Select all that apply) A: Testosterone is obtained from Androstenedione by oxidation of the C-17 OH group. B: Dihydrotestosterone (DHT) is the reduced product of Testosterone. C: Testostrone can be converted into Estradiol by the action of 5 alpha reductase. D: Hydroxylation of Vitamin D3 at C#25 (or C-25) takes place in the kidney.

B: Dihydrotestosterone (DHT) is the reduced product of Testosterone. D: Hydroxylation of Vitamin D3 at C#25 (or C-25) takes place in the kidney.

What happens to protein kinase A (PKA) following the binding of cAMP? A: The regulatory subunits of PKA dissociate, thereby activating the catalytic subunits. B: PKA catalytic subunits then bind to two regulatory subunits, thereby activating the catalytic subunits. C: Phosphodiesterase binds to the catalytic subunits, which results in enzyme inactivation (or deactivation). D: The stimulatory subunits dissociate from the catalytic subunits, inhibiting the enzyme.

A: The regulatory subunits of PKA dissociate, thereby activating the catalytic subunits.

Which of the following hormones termed “flight-or-fight” hormone is secreted by adrenal medulla? A: Glucagon B: insulin C: Epinephrine D: Oxytocin

C: Epinephrine

Which of the following is not a natural ligand that binds to G protein-coupled receptors? A: Hormones B: Neurotransmitters. C: Opium derivatices D: Steroid hormones.

D: Steroid hormones.

Which of the following statements regarding membrane lipids is false? A: Phosphatidylcholine and phosphatidylethanolamine are located primarily on the outer leaflet of the plasma membrane. B: Adenylyl cyclase is the marker enzyme for plasma membrane. C: Insulin, by recruiting glucose transports to the plasma membrane, increases uptake of glucose in fat cells but not in muscle. D: The major phospholipid by mass in human membrane is generally phosphatidylcholine.

A: Phosphatidylcholine and phosphatidylethanolamine are located primarily on the outer leaflet of the plasma membrane. B: Adenylyl cyclase is the marker enzyme for plasma membrane. C: Insulin, by recruiting glucose transports to the plasma membrane, increases uptake of glucose in fat cells but not in muscle.

Which of the following statements is incorrect (or False)? A: Phospholipases allow degradation and remodeling of phosphoglycerols. B: Lysolecithin can be formed by using Phospholipase A2 on phosphatidylcholine. C: Plasmalogen contains a saturated ether, an acyl group and an phosphoethanolamine on a glycerol molecule. D: PAF contains a saturated ether, an acyl group and a phosphocholine on a glycerol molecule.

C: Plasmalogen contains a saturated ether, an acyl group and an phosphoethanolamine on a glycerol molecule.

Which of the following statements is correct (or False)? A: Triacylglycerols are the major energy storing lipids. B: Glycosphingolipids, sphingomyelins have structural functions in cell membranes. C: Phospholipids and sphingolipids are involved in several disease processes including infant respiratory distress syndrome, multiple sclerosis and sphingolipidosis. D: GlcCer (glucosylceramide) is the major glycosphingolipid of extraneural tissues, whereas GalCer (Galactosylceramide) is the major lipid of myelin.

B: Glycosphingolipids, sphingomyelins have structural functions in cell membranes.

Which of the following statements in the metabolism of acylglycerols and sphingolipids is incorrect (or False)? A: Hydrolysis initiates catabolism of triacylglycerols. B: Diacylglycerol is the common precursor in the biosynthesis of many phosphoglycerols and cardiolipin. C: Triacylglycerols and phosphoglycerols are formed by acylation of triose phosphates. D: Deficiency of lung surfactant causes respiratory distress syndrome.

B: Diacylglycerol is the common precursor in the biosynthesis of many phosphoglycerols and cardiolipin.

Consider the various examples of Sphingolipidoses. Which of the following statements is incorrect (or False)? A: Tay-Sachs disease is due to the deficiency in hexosamindase A B: Fabry's disease is due to the deficiency in alpha Galactosidase. C: Gaucher's disease is due to the deficiency in beta Glucosidase. D: Niemann-Pick disease is due to the deficiency in Ceramidase

D: Niemann-Pick disease is due to the deficiency in Ceramidase

Consider the overview of the acylglycerol biosynthesis. Which of the followings 1/1 statements is incorrect (or False)? A: Phosphatidate is used to make Cardiolipin and Phosphatidylinositol B: Diacylglycerol is used to make Lecithin, Cephalin and Triglycerides. C: Dihydroxyacetone phosphate is used to make Plasmalogens and PAFs. D: Phosphatidate can be converted to diacylglycerol by phosphorylation.

D: Phosphatidate can be converted to diacylglycerol by phosphorylation.

Consider the biosynthesis of ceramide. Which of the following statements is incorrect (or False)? A: Ceramide is made by condensing StearoylCoA and Serine. B: In the biosynthesis process, an intermediate: 3-ketosphinganine is oxidized to dihydrosphingosine C: In the final step, dihydroceramide desaturate oxidizes dihydroceramide to ceramide. D: Dihydrosphingosine is a reduced product of 3-ketosphinganine.

A: Ceramide is made by condensing StearoylCoA and Serine.

Which of these statements about ALA synthase is incorrect (or False)? A: ALA synthase is the key regulatory enzyme in hepatic biosynthesis of heme. B: Many drugs increase cytochrome P450 biosynthesis. C: Many drugs induce ALAS1 biosynthesis and this increases heme production. D: ALAS2 is also regulated by heme and also induced by drugs.

D: ALAS2 is also regulated by heme and also induced by drugs.

Which of the following statements about the protoporhyrin ring is correct (or True)? A: It contains a tetrapyrrolidine ring in its structure B: The acetate group in uroporphyrin III is reduced to methyl groups in Coporphyrinogen C: In the metabolism of the heme, biliverdin is a linear chain containing three lactam (2-oxopyrrole) rings. D: In the metabolism of heme, bilirubin is the oxidized form of biliverdin.

A: It contains a tetrapyrrolidine ring in its structure B: The acetate group in uroporphyrin III is reduced to methyl groups in Coporphyrinogen

Which of the following statements about the catabolism of heme is incorrect (or False)? A: Catabolism of heme produces bilirubin. B: Bilirubin is transported to the liver where the degradation takes place in two stages. C: Bilirubin in the liver is picked up (or taken up) by the parenchymal cells. D: Bilirubin conjugates with the acid group of glucoruronic acid.

B: Bilirubin is transported to the liver where the degradation takes place in two stages.

Which of the following statements about hemoproteins is not correct (or False)? A: Cytochrome c is hemoprotein involved in the electron transport chain. B: Cytochrome P450 is also a hemoprotein involved in hydroxylation of xenobiotics. C: Catalase is a hemoprotein involved in the degradation of hydrogen peroxide. D: ALA synthase is a hemoprotein involved in the synthesis of delta aminolevulinate.

D: ALA synthase is a hemoprotein involved in the synthesis of delta

Which of the following statements about Heme biosynthesis and metabolism is incorrect (or False)? A: Catabolism of the heme ring by the mitochondrial enzyme heme oxygenase, produces biliverdin. B: Oxidation of biliverdin produces bilirubin which is transported to the liver bound to serum albumin. C: Most of the bilirubin excreted in bile of mammals is bilirubin diglucouronide. D: Intestinal bacteria reduce conjugated bilirubin to urobilinogen.

B: Oxidation of biliverdin produces bilirubin which is transported to the liver bound to serum albumin.

Which of the following statements about Heme biosynthesis and metabolism is incorrect (or False)? A: There are 4 methyls, 2 propionate and 2 vinyl group groups present in the four pyrrole rings of heme. B: Biosynthesis of heme involves 6 enzyme catalyzed reactions. C: Synthesis of heme commences with the condensation of succinylCoA and Glycine. D: Genetic abnormalities of seven of the eight enzymes of heme biosynthesis result in inherited porphyrias.

B: Biosynthesis of heme involves 6 enzyme catalyzed reactions.

Which of the following statements about disorders of bilirubin metabolism is incorrect (or False)? A: Neonatal physiologic jaundice, also called as the Dubin Johnson syndrome, results from decrease in the hemolysis of bilirubin because of the immature hepatic system for uptake, and conjugation of bilirubin. B: Hyperbilirubinemia causes jaundice. C: If 30% of the bilirubin UDP-glucouronosyl transferase activity is retained, Gilbert syndrome is harmless. D: Obstruction in the biliary tree is the most common cause of conjugated hyperbilirubinemia.

A: Neonatal physiologic jaundice, also called as the Dubin Johnson syndrome, results from decrease in the hemolysis of bilirubin because of the immature hepatic system for uptake, and conjugation of bilirubin.

Which of the following statements about classification of porphyrias is correct (or True)? A: Porphyrias may be termed as erythropoietic or hepatic based on the organ most affected. B: Barbiturates induce production of cytochrome P450 C: Individuals with low ALAS2 develop anemia, not porphyria D: There is no known defect of ALAS1

A: Porphyrias may be termed as erythropoietic or hepatic based on the organ most affected.

Which of the following statements about biosynthesis of heme is incorrect (or False)? A: Synthesis on of heme takes place in the cytosol B: Ferrochelatase enzyme acts on protoporphyrin III in the mitochondria. C: Oxidation of Coporphyrinogen III takes place twice in the mitochondria to form protoporphyrin III. D: Synthesis of coproporphyrinogen III takes place in the cytosol.

A: Synthesis on of heme takes place in the cytosol

Which of the following statements about ALA synthase is incorrect (or False)? A: There are two isoenzymes of ALA synthase. B: Heme acts as a positive regulator of the synthesis of ALAS1 C: ALAS2 is expressed in erythrocytes. D: ALAS1 is expressed throughout the body.

B: Heme acts as a positive regulator of the synthesis of ALAS1

Rapid uptake or release of glucose takes place in the liver. Which of the following glucose transporters facilitates the bidirectional transport of glucose? A: GLUT 1 B: GLUT 2 C: GLUT 3 D: GLUT 4

B: GLUT 2

In the transcellular movement of glucose in a intestinal cell, Glucose follows which of the following ions across the luminal epithelial membrane? A: Ca+2 B: K+ C: Na+ D: Cl-

C: Na+

Which of the following statement is not correct (or False)? A: Phospholipids constitute one of the major components of a lipid membrane B: Glycolipids constitute one of the major components of a lipid membrane C: Cholesterol constitutes one of the major components of a lipid membrane D: Triacylglycerols constitute one of the major components of a lipid membrane

D: Triacylglycerols constitute one of the major components of a lipid membrane

Which of the following molecules is transported very easily through the lipid bilayer? A: O2 B: Na+ C: Cl- D: Indole

A: O2

Which of the following membranes has a higher lipid to protein ratio? A: Mitochondrial B: Myelin C: Sarcoplasmic reticulum D: Retinal rods

B: Myelin

Which of the following descriptions represents the stoichiometry of a Na+-K+ ATpase? A: 3 Na+ ions moving in and 1 K+ ions out. B: 3 Na+ ions moving out and 1 K+ ions moving in. C: 3Na+ ions moving out and 2K+ ions moving in. D: 3Na+ ions moving out and 2K+ ions moving out.

C: 3Na+ ions moving out and 2K+ ions moving in.

In the biosynthesis of Pyrimidines, which of the following amino acids combines with CO2 to form carbamoylphosphate? A: Asparagine B: Glutamine C: Lysine D: Aspartate

B: Glutamine

Humans catabolize purines to which of the following metabolized products? A: Arginine B: Xanthine C: Uric acid D: Beta-alanine

C: Uric acid

In the biosynthesis of purines, which of the following is the first amino acid to be incorporated onto the phosphoribosylpyrophosphate molecule? A: Glycine B: Glutamine C: Aspartate D: Asparagine

B: Glutamine

In the biosynthesis of purines, which of the following molecules lost in one of the processes is an intermediate in the TCA cycle? A: Succinate B: Fumarate C: Maleate D: Citrate

B: Fumarate

Which of the following is considered a secondary messenger? A: ATP B: Xanthine C: AcetylCholine D: cAMP

D: cAMP

In the biosynthesis of purines, the N#3 atom is contributed by which amino acid? A: Glycine B: N5,N10-Methenyltetrahydrofolate C: Glutamine D: Aspartate

C: Glutamine

Which of the following nucleotide derivatives act as intermediates for lipid biosynthesis? A: UDP-Glucose B: CDP-Acylglycerol C: cAMP D: ATP

B: CDP-Acylglycerol

In which of the following bases is the amino group (-NH2) at the #2 carbon of the fused heterocyclic ring? A: Adenine B: Guanine C: Cytosine D: Uracil

B: Guanine

In the biosynthesis of purines, the N#1 atom is contributed by which amino acid? A: Glycine B: N5,N10-Methenyltetrahydrofolate C: Glutamine D: Aspartate

D: Aspartate

In the biosynthesis of purines, the N#9 atom is contributed by which amino acid? A: Glycine B: N5,N10-Methenyltetrahydrofolate C: Glutamine D: Aspartate

C: Glutamine

In the biosynthesis of purines. Inosine monophosphate (IMP) is converted to AMP in a two step process using which of the following amino acids? A: Glutamine B: Glutamate C: Arginine D: Aspartate

D: Aspartate

In the biosynthesis of Pyrimidines, which of the following amino acids combines with Carbamoylphosphate? A: Asparagine B: Glutamine C: Lysine D: Aspartate

D: Aspartate

In the biosynthesis of purines, Inosine monophosphate is converted to GMP in a two-step process using which of the following amino acids? A: Glutamine B: Glutamate C: Arginine D: Aspartate

A: Glutamine

Which of the following is one of the intermediates in the biosynthesis of Pyrimidines? A: Beta-Alanine B: Inosine monophosphate C: Orotic acid D: Xanthine

C: Orotic acid

In the biosynthesis of purines, which of the following is the second amino acid to be incorporated onto the phosphoribosylamine molecule? A: Glycine B: Glutamine C: Aspartate D: Alanine

A: Glycine

In the biosynthesis of Pyrimidines, UMP is converted to CTP using which of the following amino acids? A: Asparagine B: Glutamine C: Lysine D: Aspartate

B: Glutamine

Which of the following statements is incorrect (or False)? A: When Mononucleotides linked 3 prime to 5 prime are represented as TGATCA, 5 prime is on the left. B: Synthetic analogs of purines and pyrimidines are used as anticancer drugs. C: Nucleotides participate in metabolic functions, energy metabolism, protein synthesis, regulation of enzyme activity, and signal transduction. D: Adenine contains a 1o amine on carbon number 2

D: Adenine contains a 1o amine on carbon number 2

Which of the following statements is incorrect (or False)? A: Nucleoside triphosphates have a low group transfer potential. B: The Nucleoside triphosphates participate in covalent bond synthesis. C: cAMP and cGMP function as intracellular second messengers. D: All phosphodiester bonds are 3 prime to 5 prime.

A: Nucleoside triphosphates have a low group transfer potential.

Which of the following statements is incorrect (or False)? A: Carbon 2 on Cytosine contains the oxo group. B: Thymine and Uracil have Oxo groups on 2 and 4. C: Guanine has a 1o amine on carbon 4. D: Cytidine and Uridine have glycosidic bond at carbon number 1

C: Guanine has a 1o amine on carbon 4.

Which of the following statements is incorrect (or False)? A: The ribose or deoxy ribose is linked to N-1 of a purine and N-9 of a pyrimidine. B: The bond formed between the N-1 and N-9 with the purine and pyrimidine is a B-glycosidic bond. C: Purines are considered as heterocycles that are formed by the fusion of pyrimidine and imidazole. D: A prime number indicates the amine to which the phosphoryl group of the sugars mononucleotides is attached.

D: A prime number indicates the amine to which the phosphoryl group of the sugars mononucleotides is attached.

Which of the following hormones uses the receptor that is in complex with a heat shock protein? A: Thyroid hormones B: Glucocorticoid hormones C: Catecholamines D: Parathyroid hormone

A: Thyroid hormones B: Glucocorticoid hormones

Which of the following best fits the description of an inactive G-protein? A: It is heterotrimeric which is bound by GTP B: It is heterodimeric which is bound by GDP C: It is heterotetrameric which is bound by GDP D: It is heterotrimeric which is bound by GDP

D: It is heterotrimeric which is bound by GDP

The production of which of the following is increased by the binding of Atriopeptins, a family of peptides that cause vasodilation in the cardiac muscle? A: cAMP B: cGMP C: AMP D: GTP

B: cGMP

Uric acid is a derivative of which of the following heterocyclic bases? A: Adenine B: Cytosine C: Uracil D: Thymine

A: Adenine

Which of the following is classified as an aminopeptide hormone? A: Pregnenolone B: Dihydrotestosterone C: Calcitriol D: Parathyroid

D: Parathyroid

Which of the following statements about Group I and Group II hormones are incorrect (False)? (Select all that apply) A: Calcitriol are classified as Group II hormones and are Lipophilic in nature. B: Catecholamines are classified as hormones that interact via (or with) intracellular receptors. C: The half life of Group I hormones are very short (minutes) D: Group II hormones use secondary messengers like Ca+2, cAMP, cGMP

A: Calcitriol are classified as Group II hormones and are Lipophilic in nature. B: Catecholamines are classified as hormones that interact via (or with) intracellular receptors. C: The half life of Group I hormones are very short (minutes)

Which of the following statements about the classification of hormones are correct (or True). (Select all that apply) A: Glucocorticoid is an example of a hormone that binds to intracellular receptors. B: Atrial Natriuretic factor uses cAMP as secondary messenger C: Vasopressin (Antidiuretic hormone) uses Ca+2 as a secondary messenger D: Glucagon uses cGMP as secondary messenger

A: Glucocorticoid is an example of a hormone that binds to intracellular receptors. C: Vasopressin (Antidiuretic hormone) uses Ca+2 as a secondary messenger

Which of the following statements about biosynthesis of prohormones are correct (or True) (Select all that apply) A: PTH is an 84 amino acid peptide B: Angiotensin II is an octapeptide from Angiotensinogen (about 400 amino acids). C: Angiotensin Converting Enzyme (ACE), a glycoprotein found in the lungs, endothelial cells and plasma removes 2 amino acids from the decapeptide, Angiotensin I to form Angiotensin II D: Insulin is synthesized as a preprohormone and modified to form the two chains of 21 and 30 amino acids each.

A: PTH is an 84 amino acid peptide B: Angiotensin II is an octapeptide from Angiotensinogen (about 400 amino acids). C: Angiotensin Converting Enzyme (ACE), a glycoprotein found in the lungs, endothelial cells and plasma removes 2 amino acids from the decapeptide, Angiotensin I to form Angiotensin II D: Insulin is synthesized as a preprohormone and modified to form the two chains of 21 and 30 amino acids each.

Which of the following statements about Biosynthesis of various hormones are correct (or True)? (Select all that apply) A: Pregnenolone is synthesized from Cholesterol using P450scc B: Cortisol synthesis requires 3 hydroxylases at C11, C17 and C21 C: The major androgen precursor produced by the adrenal cortex is dehydroepiandosterone (DHEA) D: The most significant metabolic product of testosterone is DHT (Dihydrotesterone) which is obtained from Testosterone using 5 alpha reductase

A: Pregnenolone is synthesized from Cholesterol using P450scc B: Cortisol synthesis requires 3 hydroxylases at C11, C17 and C21 C: The major androgen precursor produced by the adrenal cortex is dehydroepiandosterone (DHEA) D: The most significant metabolic product of testosterone is DHT (Dihydrotesterone) which is obtained from Testosterone using 5 alpha reductase

Angiotensin III is formed from Angiotensin II by which of the following enzymes? A: Renin B: Converting enzyme C: Aminopeptidase D: Angiotensinases

C: Aminopeptidase