The enzyme which catalyzes the unwinding of DNA helix during replication is: (1) Primase (2) Topoisomerase (3) Helicase (4) DNA polymerase

The enzyme which catalyzes the unwinding of DNA helix during replication is: (1) Primase (2) Topoisomerase (3) Helicase (4) DNA polymerase
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(3) Helicase Explanation: A type of helicase enzyme called DNA helicase catalyzes the unwinding of the DNA helix at the time of replication. It uses the energy released through hydrolysis of ATP (Adenosine triphosphate) to break the hydrogen bonds between the two strands. The enzyme is needed to separate the two strands of DNA also during transcription and DNA repair.
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The enzyme which catalyzes the unwinding of DNA helix during replication is: (1) Primase (2) Topoisomerase (3) Helicase (4) DNApolymerase

Description : The enzyme which catalyzes the unwinding of DNA helix during replication is: (1) Primase (2) Topoisomerase (3) Helicase (4) DNApolymerase

Last Answer : C option is the answer

During DNA replication, the strands separate by (a) DNA polymerase (b) topoisomerase (c) unwindase/helicase (d) gyrase.

Description : During DNA replication, the strands separate by (a) DNA polymerase (b) topoisomerase (c) unwindase/helicase (d) gyrase.

Last Answer : b) topoisomerase

There are special proteins that help to open up DNA double helix in front of the replication fork. These proteins are (a) DNA ligase (b) DNA topoisomerase I (c) DNA gyrase (d) DNA polymerase I.

Description : There are special proteins that help to open up DNA double helix in front of the replication fork. These proteins are (a) DNA ligase (b) DNA topoisomerase I (c) DNA gyrase (d) DNA polymerase I.

Last Answer : (c) DNA gyrase

Name the enzyme that facilitates opening of DNA helix during transcription. (a) DNA ligase (b) DNA helicase (c) DNA polymerase (d) RNA polymerase

Description : Name the enzyme that facilitates opening of DNA helix during transcription. (a) DNA ligase (b) DNA helicase (c) DNA polymerase (d) RNA polymerase

Last Answer : b) DNA helicase

The enzyme adds complementary bases to the DNA template strand during replication. a. Ligase b. Helicase c. DNA polymerase III d. RNA polymerase

Description : The enzyme adds complementary bases to the DNA template strand during replication. a. Ligase b. Helicase c. DNA polymerase III d. RNA polymerase

Last Answer : d. RNA polymerase

In DNA replication the enzyme required in the first step is (A) DNA directed polymerase (B) Unwinding proteins (C) DNA polymerase (D) DNA ligase

Description : In DNA replication the enzyme required in the first step is (A) DNA directed polymerase (B) Unwinding proteins (C) DNA polymerase (D) DNA ligase

Last Answer : Answer : B

Enzyme which can break and seal the DNA strand a) Topoisomease II (b) Helicase (c) Primase (d) Restriction endonuclease

Description : Enzyme which can break and seal the DNA strand a) Topoisomease II (b) Helicase (c) Primase (d) Restriction endonuclease

Last Answer : a) Topoisomease II

During replication, unwinding of double helix is initiated by (A) DNAA protein (B) DnaB protein (C) DNAC protein (D) Rep protein

Description : During replication, unwinding of double helix is initiated by (A) DNAA protein (B) DnaB protein (C) DNAC protein (D) Rep protein

Last Answer : Answer : B

Helicase and DNAB protein cause (A) Rewinding of DNA and require ATP as a source of energy (B) Rewinding of DNA but do not require any source of energy (C) Unwinding of DNA and require ATP as a source of energy (D) Unwinding of DNA but do not require any source of energy

Description : Helicase and DNAB protein cause (A) Rewinding of DNA and require ATP as a source of energy (B) Rewinding of DNA but do not require any source of energy (C) Unwinding of DNA and require ATP as a source of energy (D) Unwinding of DNA but do not require any source of energy

Last Answer : Answer : C

From a DNA-RNA hybrid, DNA can be obtained by addition of (A) DNA B protein and ATP (B) Helicase and ATP (C) DNA topoisomerase I (D) Alkali

Description : From a DNA-RNA hybrid, DNA can be obtained by addition of (A) DNA B protein and ATP (B) Helicase and ATP (C) DNA topoisomerase I (D) Alkali

Last Answer : Answer : D

RNA primer is formed by the enzyme: (A) Ribonuclease (B) Primase (C) DNA polymerase I (D) DNA polymerase III

Description : RNA primer is formed by the enzyme: (A) Ribonuclease (B) Primase (C) DNA polymerase I (D) DNA polymerase III

Last Answer : Answer : B

Rifampicin inhibits (A) Unwinding of DNA (B) Initiation of replication (C) Initiation of translation (D) Initiation of transcription

Description : Rifampicin inhibits (A) Unwinding of DNA (B) Initiation of replication (C) Initiation of translation (D) Initiation of transcription

Last Answer : Answer : D

An important step in protein synthesis is transcription. Which of the following statement(s) is/are true concerning this process? a. The first step in gene transcription involves separating the double helix of DNA by an enzyme known as DNA polymerase b. The initial product of DNA transcription is called heterogeneous nuclear RNA which codes directly for proteins c. After processing is complete, the mRNA is exported from the nucleus to the cytoplasm d. Only one protein can be produced from an initial mRNA strand

Description : An important step in protein synthesis is transcription. Which of the following statement(s) is/are true concerning this process? a. The first step in gene transcription involves separating the double helix ... nucleus to the cytoplasm d. Only one protein can be produced from an initial mRNA strand

Last Answer : Answer: c Transcription of a gene begins at an initiation site associated with a specific DNA sequence, termed a promoter region. After binding to DNA, the RNA polymerase opens up a short ... different proteins from the same gene. mRNA is exported from the nucleus only after processing is complete

DNA topoisomerase I of E. coli catalyses (A) Relaxation of negatively supercoiled DNA (B) Relaxation of positively supercoiled DNA (C) Conversion of negatively supercoiled DNA into positively supercoiled DNA (D) Conversion of double helix into supercoiled DNA

Description : DNA topoisomerase I of E. coli catalyses (A) Relaxation of negatively supercoiled DNA (B) Relaxation of positively supercoiled DNA (C) Conversion of negatively supercoiled DNA into positively supercoiled DNA (D) Conversion of double helix into supercoiled DNA

Last Answer : Answer : A

The removal of which enzyme affects the synthesis of hnRNA in eukaryotes a) RNA polymerase II b) RNA primase c) RNA polymerase III d) RNA polymerase I

Description : The removal of which enzyme affects the synthesis of hnRNA in eukaryotes a) RNA polymerase II b) RNA primase c) RNA polymerase III d) RNA polymerase I

Last Answer : a) RNA polymerase II

Negative supercoils are introduced in DNA by (A) Helicase (B) DNA ligase (C) DNA gyrase (D) DNA polymerase III holoenzyme

Description : Negative supercoils are introduced in DNA by (A) Helicase (B) DNA ligase (C) DNA gyrase (D) DNA polymerase III holoenzyme

Last Answer : Answer : C

A consensus sequence on DNA, called TATA box, is the site for attachment of (A) RNA-dependent DNA polymerase (B) DNA-dependent RNA polymerase (C) DNA-dependent DNA polymerase (D) DNA topoisomerase II

Description : A consensus sequence on DNA, called TATA box, is the site for attachment of (A) RNA-dependent DNA polymerase (B) DNA-dependent RNA polymerase (C) DNA-dependent DNA polymerase (D) DNA topoisomerase II

Last Answer : Answer : B

DNA fragments are sealed by (A) DNA polymerase II (B) DNA ligase (C) DNA gyrase (D) DNA topoisomerase II

Description : DNA fragments are sealed by (A) DNA polymerase II (B) DNA ligase (C) DNA gyrase (D) DNA topoisomerase II

Last Answer : Answer : B

The region of DNA known as TATA BOX is the site for binding of (A) DNA polymerase (B) DNA topoisomerase (C) DNA dependent RNA polymerase (D) Polynucleotide phosphorylase

Description : The region of DNA known as TATA BOX is the site for binding of (A) DNA polymerase (B) DNA topoisomerase (C) DNA dependent RNA polymerase (D) Polynucleotide phosphorylase

Last Answer : Answer : C

DNA-dependent RNA polymerase catalyzes transcription on one strand of the DNA which is called the

Description : DNA-dependent RNA polymerase catalyzes transcription on one strand of the DNA which is called the

Last Answer : DNA-dependent RNA polymerase catalyzes transcription on one strand of the DNA which is called the ... Antistrand C. Template strand D. Coding strand

In addition to Taq polymerase, polymerase chain reaction requires all of the following except (A) A template DNA (B) Deoxyribonucleoside triphosphates (C) Primers (D) Primase

Description : In addition to Taq polymerase, polymerase chain reaction requires all of the following except (A) A template DNA (B) Deoxyribonucleoside triphosphates (C) Primers (D) Primase

Last Answer : Answer : D

Primase activity is present in (A) DNA polymerase II (B) DNA polymerase α (C) DNA polymerase β (D) DNA polymerase δ

Description : Primase activity is present in (A) DNA polymerase II (B) DNA polymerase α (C) DNA polymerase β (D) DNA polymerase δ

Last Answer : Answer : B

Which of the following enzymes are used to join bits of DNA? (a) Ligase (b) Primase (c) DNA polymerase (d) Endonuclease

Description : Which of the following enzymes are used to join bits of DNA? (a) Ligase (b) Primase (c) DNA polymerase (d) Endonuclease

Last Answer : a) Ligase

Which of the following molecule catalyzes the transpeptidation reaction? A.RNA polymerase B.Peptidyl transferase C.DNA ligase D.DNA polymerase

Description : Which of the following molecule catalyzes the transpeptidation reaction? A.RNA polymerase B.Peptidyl transferase C.DNA ligase D.DNA polymerase

Last Answer : B.Peptidyl transferase

Which of the following molecule catalyzes the transpeptidation reaction? A- RNA Polymerase B- Peptidlytransferase C- DNA ligase D- DNA polymerase

Description : Which of the following molecule catalyzes the transpeptidation reaction? A- RNA Polymerase B- Peptidlytransferase C- DNA ligase D- DNA polymerase

Last Answer : Peptidlytransferase

Which of the following molecule catalyzes the transpeptidation reaction? A- RNA polymeraseB- .Peptidyltransferase C- DNA ligase D- .DNA polymerase

Description : Which of the following molecule catalyzes the transpeptidation reaction? A- RNA polymerase B- .Peptidyltransferase C- DNA ligase D- .DNA polymerase

Last Answer : .Peptidyltransferase

Which of the following molecule catalyzes the transpeptidation reaction? A- RNA Polymerase B- Peptidlytransferase C- DNA ligase D- DNA polymerase

Description : Which of the following molecule catalyzes the transpeptidation reaction? A- RNA Polymerase B- Peptidlytransferase C- DNA ligase D- DNA polymerase

Last Answer : Peptidlytransferase

Which of the following molecule catalyzes the transpeptidation reaction? A- RNA polymeraseB- .Peptidyltransferase C- DNA ligase D- .DNA polymerase

Description : Which of the following molecule catalyzes the transpeptidation reaction? A- RNA polymerase B- .Peptidyltransferase C- DNA ligase D- .DNA polymerase

Last Answer : .Peptidyltransferase

Indicate the enzyme(s) inhibited by fluoroquinolones: A. Both 'A' and 'C' B. Topoisomerase II C. Topoisomerase IV D. DNA gyrase

Description : Indicate the enzyme(s) inhibited by fluoroquinolones: A. Both 'A' and 'C' B. Topoisomerase II C. Topoisomerase IV D. DNA gyrase

Last Answer : D. DNA gyrase

Function of DNA polymerase during DNA replication. -Biology

Description : Function of DNA polymerase during DNA replication. -Biology

Last Answer : answer:

What is the role of the enzyme DNA primase?

Description : What is the role of the enzyme DNA primase?

Last Answer : Primase is an enzyme that synthesizes short RNA sequences called primers which serve as a starting point for DNA synthesis. Since primase produces RNA molecules, the enzyme is a type of RNA ... strand of nucleotides. Therefore, primase serves to prime and lay a foundation for DNA synthesis.

The association of histone H1 with a nucleosome indicates that (a) DNA replication is occurring (b) the DNA is condensed into a chromatin fibre (c) the DNA double helix is exposed (d) transcription is occurring.

Description : The association of histone H1 with a nucleosome indicates that (a) DNA replication is occurring (b) the DNA is condensed into a chromatin fibre (c) the DNA double helix is exposed (d) transcription is occurring.

Last Answer : (b) the DNA is condensed into a chromatin fibre

The association of histone H1 with a nucleosome indicates: (1) DNA replication is occurring. (2) The DNA is condensed into a Chromatin Fibre. (3) The DNA double helix is exposed. (4) Transcription is occurring.

Description : The association of histone H1 with a nucleosome indicates: (1) DNA replication is occurring. (2) The DNA is condensed into a Chromatin Fibre. (3) The DNA double helix is exposed. (4) Transcription is occurring.

Last Answer : (2) The DNA is condensed into a Chromatin Fibre.

In the process of transcription in bacterial cells (A) Initiation requires rho protein (B) RNA polymerase incorporates methylated bases in correct sequence (C) Both the sigma unit and core enzymes of RNA polymerase are required for accurate promotor site binding (D) Primase is necessary for initiation

Description : In the process of transcription in bacterial cells (A) Initiation requires rho protein (B) RNA polymerase incorporates methylated bases in correct sequence (C) Both the sigma unit and core ... RNA polymerase are required for accurate promotor site binding (D) Primase is necessary for initiation

Last Answer : Answer : C

Which of the following reunites the exon segments after RNA splicing? (a) RNA polymerase (b) RNA primase (c) RNA ligase (d) RNA proteose

Description : Which of the following reunites the exon segments after RNA splicing? (a) RNA polymerase (b) RNA primase (c) RNA ligase (d) RNA proteose

Last Answer : a) RNA polymerase

Which of the following reunites the exon segments after RNA splicing? (a) RNA polymerase (b) RNA primase (c) RNA ligase (d) RNA proteoses

Description : Which of the following reunites the exon segments after RNA splicing? (a) RNA polymerase (b) RNA primase (c) RNA ligase (d) RNA proteoses

Last Answer : (c) RNA ligase

What is the role of DNA polymerase in DNA replication? -Biology

Description : What is the role of DNA polymerase in DNA replication? -Biology

Last Answer : answer:

Template-directed DNA synthesis occurs in all the following except (A) The replication fork (B) Polymerase chain reaction (C) Growth of RNA tumor viruses (D) Expression of oncogenes

Description : Template-directed DNA synthesis occurs in all the following except (A) The replication fork (B) Polymerase chain reaction (C) Growth of RNA tumor viruses (D) Expression of oncogenes

Last Answer : Answer : C

Template-directed DNA synthesis occurs in all the following except (A) The replication fork (B) Polymerase chain reaction (C) Growth of RNA tumor viruses (D) Expression of oneogenes

Description : Template-directed DNA synthesis occurs in all the following except (A) The replication fork (B) Polymerase chain reaction (C) Growth of RNA tumor viruses (D) Expression of oneogenes

Last Answer : Answer : C

DNA contains some palindromic sequences which (A) Mark the site for the formation of replication forks (B) Direct DNA polymerase to turn back to replicate the other strand (C) Are recognized by restriction enzymes (D) Are found only in bacterial DNA

Description : DNA contains some palindromic sequences which (A) Mark the site for the formation of replication forks (B) Direct DNA polymerase to turn back to replicate the other strand (C) Are recognized by restriction enzymes (D) Are found only in bacterial DNA

Last Answer : Answer : C

Replication of nuclear DNA in mammals is catalysed by (A) DNA polymerase α (B) DNA polymerase β (C) DNA polymerase γ (D) DNA polymerase III

Description : Replication of nuclear DNA in mammals is catalysed by (A) DNA polymerase α (B) DNA polymerase β (C) DNA polymerase γ (D) DNA polymerase III

Last Answer : Answer : A

3’→5’ Exonuclease activity of DNA polymerase I (A) Removes ribonucleotides (B) Adds deoxyribonucleotides (C) Corrects errors in replication (D) Hydrolyses DNA into mononucleotides

Description : 3’→5’ Exonuclease activity of DNA polymerase I (A) Removes ribonucleotides (B) Adds deoxyribonucleotides (C) Corrects errors in replication (D) Hydrolyses DNA into mononucleotides

Last Answer : Answer : C

At a chromosome replication fork, the lagging strand consists of__ That is joined by___. a. RNA sequences; DNA ligase b. Okazaki Fragments; RNA Polymerase c. RNA sequences; ribosomes d. Okazaki fragments; DNA ligase

Description : At a chromosome replication fork, the lagging strand consists of__ That is joined by___. a. RNA sequences; DNA ligase b. Okazaki Fragments; RNA Polymerase c. RNA sequences; ribosomes d. Okazaki fragments; DNA ligase

Last Answer : d. Okazaki fragments; DNA ligase

For unwinding of double helical DNA, (A) Energy is provided by ATP (B) Energy is provided by GTP (C) Energy can be provided by either ATP or GTP (D) No energy is required

Description : For unwinding of double helical DNA, (A) Energy is provided by ATP (B) Energy is provided by GTP (C) Energy can be provided by either ATP or GTP (D) No energy is required

Last Answer : Answer : A

The enzyme DNA ligase (A) Introduces superhelical twists (B) Connects the end of two DNA chains (C) Unwinds the double helix (D) Synthesises RNA primers

Description : The enzyme DNA ligase (A) Introduces superhelical twists (B) Connects the end of two DNA chains (C) Unwinds the double helix (D) Synthesises RNA primers

Last Answer : Answer : B

Leishmania donovani is susceptible to certain antifungal drugs because both fungi and Leishmania: A. Utilise purine salvage pathway B. Utilise similar glycolytic mechanisms C. Have similar topoisomerase II enzyme D. Have ergosterol in their cell membranes

Description : Leishmania donovani is susceptible to certain antifungal drugs because both fungi and Leishmania: A. Utilise purine salvage pathway B. Utilise similar glycolytic mechanisms C. Have similar topoisomerase II enzyme D. Have ergosterol in their cell membranes

Last Answer : D. Have ergosterol in their cell membranes

Distinctive features of gatifloxacin include the following except: A. Higher affinity for the enzyme topoisomerase IV B. Activity restricted to gram negative bacteria C. Potential to prolong QTc interval D. Employed to treat community acquired pneumonia

Description : Distinctive features of gatifloxacin include the following except: A. Higher affinity for the enzyme topoisomerase IV B. Activity restricted to gram negative bacteria C. Potential to prolong QTc interval D. Employed to treat community acquired pneumonia

Last Answer : B. Activity restricted to gram negative bacteria

What enzyme catalyzes phosphodiester bond? -Biology

Description : What enzyme catalyzes phosphodiester bond? -Biology

Last Answer : answer:

An enzyme catalyzes the conversion of an aldose sugar to a ketose sugar would be classified as one of the (A) Transferases (B) Isomerases (C) Oxido reductases (D) Hydrolases

Description : An enzyme catalyzes the conversion of an aldose sugar to a ketose sugar would be classified as one of the (A) Transferases (B) Isomerases (C) Oxido reductases (D) Hydrolases

Last Answer : Answer : B

What is the chemical equation of the formation of bicarbonate from carbon dioxide and water? What is the enzyme that catalyzes this reaction?

Description : What is the chemical equation of the formation of bicarbonate from carbon dioxide and water? What is the enzyme that catalyzes this reaction?

Last Answer : The chemical equation of the chemical equilibrium of the formation of bicarbonate having as reagents carbon dioxide and water is as follows: CO2 + H20 --> H2CO3 --> H+ + HCO3- The reaction is catalyzed by the enzyme carbonic anhydrase present in red blood cells.