R4RIN – MCQs, Mock Tests | Biochemistry Biochemistry MCQS PAPER SET 3

PCR can be used to amplify a specific fragment of DNA from which of the following?"

1. A drop of blood
2. A hair follicle
3. A fragment of skin
4. All of these

✅ Correct Answer: 4

Transformation means

1. formation of a pilus
2. acquiring DNA from the bacterial cell environment
3. plasmid containing a F factor
4. F+ and F- strains of bacteria

✅ Correct Answer: 2

Restriction maps

1. allows comparison between DNA molecules without the need to determine nucleotide sequence
2. allows comparison between DNA molecules but requires to determine nucleotide sequence
3. does not allow comparison between DNA molecules
4. none of the above

✅ Correct Answer: 1

Which of the following is correct?

1. HIV is a retrovirus that kills human helper T cells
2. Causes acquired immune deficiency syndrome (AIDS)
3. Cripples the immunity systems
4. All of the above

✅ Correct Answer: 4

A PCR cycle consists of

1. three steps, denaturation, primer annealing and elongation
2. three steps, denaturation, initiation and elongation
3. three steps, primer annealing, elongation and termination
4. three steps, initiation, elongation and termination

✅ Correct Answer: 1

How many ds DNA molecule can be produced, which comprise precisely the target region in double strand form during 4th cycle of PCR?

1. Two ds DNA molecule
2. Three ds DNA molecule
3. Eight ds DNA molecule
4. Four ds DNA molecule

✅ Correct Answer: 4

PCR can be used in

1. cloning
2. sequencing
3. medical diagnosis and forensic medicine
4. all of the above

✅ Correct Answer: 4

PCR (Polymerase Chain Reaction) can make multiple copies of

1. DNA
2. RNA
3. protein
4. carbohydrate

✅ Correct Answer: 1

PCR is an abbreviation for

1. Protein Change Reaction
2. Polymerase Chain Reaction
3. Positive Charge Reaction:
4. Preliminary Change Rate

✅ Correct Answer: 2

PCR amplifies millions of copies of

1. a short fragment of DNA
2. the entire genome (all the DNA in a sample)
3. both (a) and (b)
4. short chain RNA

✅ Correct Answer: 1

Southern blotting involves

1. electrophoresis of DNA molecules and then blotting the separated DNA bands followed by incubation
2. electrophoresis of DNA molecules and then blotting the separated RNA bands followed by incubation
3. electrophoresis of DNA molecules followed by incubation
4. electrophoresis of RNA molecules and then blotting the separated RNA bands followed by incubation

✅ Correct Answer: 1

Bactriophages absorb to a bacterial surface and inject the phage DNA through the

1. cell wall into cytosol
2. cell wall into plasmamembrane
3. both (a) and (b)
4. cell wall into endoplasmic reticulum

✅ Correct Answer: 1

In a PCR reaction after four cycles, each molecule of a duplex DNA will give rise to

1. 16 single strands of DNA
2. 16 double stranded DNA
3. 18 single strands of DNA
4. 18 double stranded DNA

✅ Correct Answer: 1

Additional mono saccharides are added in Golgi to produce

1. either high mannose type oligosaccharide or a complex type
2. either fructose type monosaccharide or a complex type
3. either high sucrose type polysaccharide or a complex type
4. none of the above

✅ Correct Answer: 1

The PCR, polymerase chain reaction is becoming the method of choice for

1. Alteration of gene
2. screening gene
3. sterilization of gene
4. all of these

✅ Correct Answer: 2

Northern blotting is

1. widely different than southern blotting
2. another name for southern blotting
3. analogous to southern blotting
4. none of the above

✅ Correct Answer: 3

What technique can be used to determine the murderer who left blood with the victim?

1. DNA sequencing
2. PCR amplification
3. Western blot
4. RFLP mapping

✅ Correct Answer: 2

DNA fragments in a restriction digest can be separated by electrophoresis in

1. poly acrylamide
2. agarose gel
3. both (a) and (b)
4. none of these

✅ Correct Answer: 3

Glycolytic pathway regulation involves

1. allosteric stimulation by ADP
2. allosteric inhibition by ATP
3. feedback, or product, inhibition by ATP
4. all of the above

✅ Correct Answer: 4

During catabolism, only about 40% of the energy available from oxidizing glucose is used to synthesize ATP. Remaining 60%

1. is lost as heat
2. is used to reduce NADP
3. remains in the products of metabolism
4. is stored as fat.

✅ Correct Answer: 1

Why does the glycolytic pathway continue in the direction of glucose catabolism?

1. There are essentially three irreversible reactions that act as the driving force for the pathway
2. High levels of ATP keep the pathway going in a forward direction
3. The enzymes of glycolysis only function in one direction
4. Glycolysis occurs in either direction

✅ Correct Answer: 1

The released energy obtained by oxidation of glucose is stored as

1. a concentration gradient across a membrane
2. ADP
3. ATP
4. NAD+

✅ Correct Answer: 3

A kinase is an enzyme that

1. removes phosphate groups of substrates
2. uses ATP to add a phosphate group to the substrate
3. uses NADH to change the oxidation state of the substrate
4. removes water from a double bond

✅ Correct Answer: 2

During catabolism, only about 40% of the energy available from oxidizing glucose is used to synthesize ATP. Remaining 60%

1. is lost as heat
2. is used to reduce NADP
3. remains in the products of metabolism
4. is stored as fat.

✅ Correct Answer: 1

Why does the glycolytic pathway continue in the direction of glucose catabolism?

1. There are essentially three irreversible reactions that act as the driving force for the pathway
2. High levels of ATP keep the pathway going in a forward direction
3. The enzymes of glycolysis only function in one direction
4. Glycolysis occurs in either direction

✅ Correct Answer: 1

For every one molecule of sugar glucose which is oxidized __________ molecule of pyruvic acid are produced.

1. 1
2. 2
3. 3
4. 4

✅ Correct Answer: 2

In the glycogen synthase reaction, the precursor to glycogen is

1. glucose-6-P
2. UTP-glucose
3. UDP-glucose
4. glucose-1-P

✅ Correct Answer: 3

The active form of glycogen phosphorylase is phosphorylated, while the dephosphorylation of which active form occurs?

1. Glycogen synthase
2. Glycogen semisynthase
3. Glycogen hydrolase
4. Glycogen dehydrogenase

✅ Correct Answer: 1

The amount of energy received from one ATP is

1. 76 kcal
2. 7.3 kcal
3. 760 kcal
4. 1000 kcal

✅ Correct Answer: 2

The enzymes of glycolysis in a eukaryotic cell are located in the

1. intermembrane space
2. plasma membrane
3. cytosol
4. mitochondrial matrix

✅ Correct Answer: 3

When concentration of the reactants is higher than the equilibrium concentration then

1. the gibbs free energy will be positive
2. the gibbs free energy will be negative
3. more products will be formed
4. Both (b) and (c)

✅ Correct Answer: 4

Which of the following is not true of glycolysis?

1. ADP is phosphorylated to ATP via substrate level phosphorylation
2. The pathway does not require oxygen
3. The pathway oxidizes two moles of NADH to NAD+ for each mole of glucose that enters
4. The pathway requires two moles of ATP to get started catabo-lizing each mole of glucose

✅ Correct Answer: 3

In glycolysis, ATP is formed by the transfer of a high-energy phosphate from 1,3-bisphosphoglycerate to ADR No such high-energy phosphate donor has ever been isolated in mitochondria because

1. the techniques for isolating the phosphate donor are not refined enough
2. no such phosphate donor exists
3. the high-energy phosphate donor is very short-lived and difficult to isolate
4. None of the above

✅ Correct Answer: 2

ATP is from which general category of molecules?

1. Polysaccharides
2. Proteins
3. Nucleotides
4. Amino acids

✅ Correct Answer: 3

The glycolytic pathway (glucose → 2 pyruvate) is found

1. in all living organisms
2. primarily in animals excluding particles
3. only in eukaryotes
4. only in yeast

✅ Correct Answer: 1

Which of the following could act as an uncoupler of electron transport and ATP synthesis?

1. The Fo base-piece of ATP synthase (without the Fl subunit)
2. Dinitrophenol
3. neither (a) nor (b)
4. Both (a) and (b)

✅ Correct Answer: 4

Which of the following is not a mechanism for altering the flux of metabolites through the rate-determining step of a pathway?

1. Allosteric control of the enzyme activity
2. Diffusional coupling between adjacent active sites
3. Genetic control of the enzyme concentration
4. Covalent modification of the enzyme

✅ Correct Answer: 2

Phosphofructokinase, the major flux-controlling enzyme of glycolysis is allosterically inhibited and activated respectively by

1. ATP and PEP
2. AMP and Pi
3. ATP and ADP
4. Citrate and ATP

✅ Correct Answer: 3

Which of the following regulates glycolysis steps?

1. Phosphofructokinase
2. Hexose kinase
3. Pyruvate kinase
4. All of these

✅ Correct Answer: 4

During glycolysis, the major energy generating step involves

1. pyruvate kinase
2. phosphoglycerate kinase
3. glyceraldehyde-3 -dehydrogenase
4. Phosphofructokinase

✅ Correct Answer: 3

Fructose-2,6-bisphosphate

1. activates fructose-1,6-bisphosphatase
2. activates phosphofructokinase
3. inhibits fructose-1,6-bisphosphatase
4. both (b) and ©

✅ Correct Answer: 4

Glucose from the breakdown of glycogen is obtained in

1. the liver by phosphorolysis
2. the muscles by phosphorolysis
3. the muscles by hydrolysis
4. both (a) and (b)

✅ Correct Answer: 4

Glycogen has

1. α-1,4 linkag
2. α-1,6 linkages
3. α-1,4 and α-1,6 linkages
4. α-1,4 and β-1,6 linkage

✅ Correct Answer: 3

Membrane potential and the proton gradient

1. are both required to make ATP
2. are sufficient, separately, to make ATP from ADP + Pi;
3. reinforce one another when respiratory inhibitors are present
4. cancel one another when uncouplers are present

✅ Correct Answer: 1

The irreversibility of the thiokinase reactions (formation of initial acyl-CoA)

1. make this activation reaction the committed step on the pathway
2. is due to the subsequent hydrolysis of the product
3. applies only to even-chain fatty acids
4. both (a) and (b)

✅ Correct Answer: 4

Long-chain fatty acids are oxidized step-wise in one carbon units starting from the

1. carboxyl end
2. aliphatic end
3. both (a) and (b)
4. none of these

✅ Correct Answer: 1

How many molecules of acetyl-CoA are produced in oxidation of palmitic acid (C16), which involves seven rounds of oxidation?

1. 6
2. 7
3. 8
4. 9

✅ Correct Answer: 3

he oxidation of methanol (wood alcohol) in human retina tissue leads directly to the formation of

1. formaldehyde
2. sugars
3. CO2
4. none of these

✅ Correct Answer: 1

The maximum energy per gram on oxidization is yielded from

1. fat
2. protein
3. glycogen
4. starch

✅ Correct Answer: 1

The oxidation of methanol (wood alcohol) in human retina tissue indirectly leads to

1. pressure builds up
2. colour blindness
3. blindness
4. all of these

✅ Correct Answer: 3

Each cycle of β-oxidation produces

1. 1 FADH2, 1 NAD+, and 1 acetyl-CoA
2. 1 FADH2, 1 NADH and 1 acetyl-CoA
3. 1 FADH2, 1 NADH and 2 CO2 molecules
4. 1 FAD, 1 NAD+ and 2 CO2 molecules

✅ Correct Answer: 2

The three identical b subunits of the F1, complex during ATP synthesis have

1. different affinities for ATP but not for ADP
2. different affinities for ADP but not for ATP
3. different affinities for ATP and for ADP
4. similar affinities for ADP and ATP

✅ Correct Answer: 3

Where the acyl-CoA formed in the cytosol is transported for oxidation?

1. Mitochondrial matrix
2. Microsomes
3. Endoplasmic reticulum
4. Remains in cytosol

✅ Correct Answer: 1

The transport of acyl-CoA for oxidation using a shuttle involves formation of the intermediate

1. 3 acetyl-CoA
2. Acyl-coenzyme A
3. acyl-carnitine
4. None of these

✅ Correct Answer: 3

FAD is reduced to FADH2 during

1. electron transport phosphorylation
2. lactate fermentation
3. Krebs cycle
4. glycolysis

✅ Correct Answer: 3

During glycolysis, electrons removed from glucose are passed to

1. FAD
2. NAD+
3. acetyl CoA
4. pyruvic acid

✅ Correct Answer: 2

A biological redox reaction always involves

1. an oxidizing agent
2. a gain of electrons
3. a reducing agent
4. all of these

✅ Correct Answer: 4

Coenzyme Q is involved in electron transport as

1. directly to O2
2. a water-soluble electron donor
3. covalently attached cytochrome cofactor
4. a lipid-soluble electron carrier

✅ Correct Answer: 4

The carbon dioxide is primary a product of

1. Krebs cycle
2. glycolysis
3. electron transport phosphorylation.
4. lactate fermentation.

✅ Correct Answer: 1

Which of the following is not a feature of oxidative phosphorylation?

1. Direct transfer of phosphate from a substrate molecule to ADP
2. An electrochemical gradient across the inner mitochondrial membrane
3. A membrane bound ATP synthase
4. A protonmotive force

✅ Correct Answer: 1