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

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
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DNA A protein can bind only to (A) Positively supercoiled DNA (B) Negatively supercoiled DNA (C) Both (A) and (B) (D) None of these

Description : DNA A protein can bind only to (A) Positively supercoiled DNA (B) Negatively supercoiled DNA (C) Both (A) and (B) (D) None of these

Last Answer : Answer : B

Thermococcus, Methanococcus and Methano- bacterium exemplify (a) bacteria whose DNA is relaxed or positively supercoiled but which have a cytoskeleton as well as mitochondria (b) bacteria that contain a cytoskeleton and ribosomes (c) archaebacteria that contain protein homologous to eukaryotic core histones (d) archaebacteria that lack any histones resembling those found in eukaryotes but whose DNA is negatively supercoiled

Description : Thermococcus, Methanococcus and Methano- bacterium exemplify (a) bacteria whose DNA is relaxed or positively supercoiled but which have a cytoskeleton as well as mitochondria (b) bacteria that ... that lack any histones resembling those found in eukaryotes but whose DNA is negatively supercoiled

Last Answer : (c) archaebacteria that contain protein homologous to eukaryotic core histones

Melting temperature of DNA is the temperature at which (A) Solid DNA becomes liquid (B) Liquid DNA evaporates (C) DNA changes from double helix into supercoiled DNA (D) Native double helical DNA is denatured

Description : Melting temperature of DNA is the temperature at which (A) Solid DNA becomes liquid (B) Liquid DNA evaporates (C) DNA changes from double helix into supercoiled DNA (D) Native double helical DNA is denatured

Last Answer : Answer : D

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

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

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

Last Answer : (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 ( ... The enzyme is needed to separate the two strands of DNA also during transcription and DNA repair.

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

What is the criterion for DNA fragments movement on agarose gel during gel electrophoresis ? (a) The smaller the fragment size, the farther it moves. (b) Positively charged fragments move to farther end. (c) Negatively charged fragments do not move. (d) The larger the fragment size, the farther it moves.

Description : What is the criterion for DNA fragments movement on agarose gel during gel electrophoresis ? (a) The smaller the fragment size, the farther it moves. (b) Positively charged fragments move to farther end. ... charged fragments do not move. (d) The larger the fragment size, the farther it moves.

Last Answer : (a) The smaller the fragment size, the farther it moves

DNA fragments are (a) negatively charged (b) neutral (c) either positively or negatively charged depending on their size (d) positively charged

Description : DNA fragments are (a) negatively charged (b) neutral (c) either positively or negatively charged depending on their size (d) positively charged

Last Answer : (a) negatively charged

DNA fragments are: (1) Negatively charged (2) Neutral (3) Either positively or negatively charged depending on their size (4) Positively charged

Description : DNA fragments are: (1) Negatively charged (2) Neutral (3) Either positively or negatively charged depending on their size (4) Positively charged

Last Answer : (1) Negatively charged

The enzyme dopamine β-oxidase which catalyses conversion of dopamine to norepinephrine requires (A) Vitamin A (B) Vitamin C (C) Vitamin E (D) Vitamin B12

Description : The enzyme dopamine β-oxidase which catalyses conversion of dopamine to norepinephrine requires (A) Vitamin A (B) Vitamin C (C) Vitamin E (D) Vitamin B12

Last Answer : Answer : B

The structural stability of the double helix of DNA is as cribbed largely to (A) Hydrogen bonding between adjacent purine bases (B) Hydrophobic bonding between staked purine and pyrinuidine nuclei (C) Hydrogen bonding between adjacent pyrimidine bases (E) Hydrogen bonding between purine and pyrimidine bases

Description : The structural stability of the double helix of DNA is as cribbed largely to (A) Hydrogen bonding between adjacent purine bases (B) Hydrophobic bonding between staked purine and ... Hydrogen bonding between adjacent pyrimidine bases (E) Hydrogen bonding between purine and pyrimidine bases

Last Answer : Answer : D

The enzyme phosphoenolpyruvate carboxykinase catalyses the conversion of oxaloacetate to phosphoenolpyruvate requires (A) ATP (B) ADP (C) AMP (D) GTP

Description : The enzyme phosphoenolpyruvate carboxykinase catalyses the conversion of oxaloacetate to phosphoenolpyruvate requires (A) ATP (B) ADP (C) AMP (D) GTP

Last Answer : Answer : D

The enzyme glucose-6-phosphatase which catalyses the conversion of glucose 6-phosphate to glucose is not found in (A) Liver (B) Muscle (C) Intestine (D) Kidney

Description : The enzyme glucose-6-phosphatase which catalyses the conversion of glucose 6-phosphate to glucose is not found in (A) Liver (B) Muscle (C) Intestine (D) Kidney

Last Answer : Answer : B

The enzyme acyl-CoA synthase catalyses the conversion of a fatty acid of an active fatty acid in the presence of (A) AMP (B) ADP (C) ATP (D) GTP

Description : The enzyme acyl-CoA synthase catalyses the conversion of a fatty acid of an active fatty acid in the presence of (A) AMP (B) ADP (C) ATP (D) GTP

Last Answer : Answer : C

Which one of the following statements concerning glucose metabolism is correct? (A) The conversion of Glucose to lactate occurs only in the R.B.C (B) Glucose enters most cells by a mechanism in which Na+ and glucose are co-transported (C) Pyruvate kinase catalyses an irreversible reaction (D) An elevated level of insulin leads to a decreased level of fructose 2, 6-bisphosphate in hepatocyte

Description : Which one of the following statements concerning glucose metabolism is correct? (A) The conversion of Glucose to lactate occurs only in the R.B.C (B) Glucose enters most cells by a mechanism in ... ) An elevated level of insulin leads to a decreased level of fructose 2, 6-bisphosphate in hepatocyte

Last Answer : C

The true statement about solutions of amino acids at physiological pH is (A) All amino acids contain both positive and negative charges (B) All amino acids contain positively charged side chains (C) Some amino acids contain only positive charge (D) All amino acids contain negatively charged side chains

Description : The true statement about solutions of amino acids at physiological pH is (A) All amino acids contain both positive and negative charges (B) All amino acids contain positively charged side chains ... amino acids contain only positive charge (D) All amino acids contain negatively charged side chains

Last Answer : Answer : A

The true statement about solutions of amino acids at physiological pH is (A) All amino acids contain both positive and negative charges (B) All amino acids contain positively charged side chains (C) Some amino acids contain only positive Charge (D) All amino acids contain negatively charged side chains

Description : The true statement about solutions of amino acids at physiological pH is (A) All amino acids contain both positive and negative charges (B) All amino acids contain positively charged side chains ... amino acids contain only positive Charge (D) All amino acids contain negatively charged side chains

Last Answer : (A) All amino acids contain both positive and negative charges

Left handed double helix is present in (A) Z-DNA (B) A-DNA (C) B-DNA (D) None of these

Description : Left handed double helix is present in (A) Z-DNA (B) A-DNA (C) B-DNA (D) None of these

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

The width (helical diameter) of the double helix in B-form DNA in nm is (A) 1 (B) 2 (C) 3 (D) 4

Description : The width (helical diameter) of the double helix in B-form DNA in nm is (A) 1 (B) 2 (C) 3 (D) 4

Last Answer : Answer : B

Mitochondrial DNA is (A) Circular double stranded (B) Circular single stranded (C) Linear double helix (D) None of these

Description : Mitochondrial DNA is (A) Circular double stranded (B) Circular single stranded (C) Linear double helix (D) None of these

Last Answer : A

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

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

Reverse transcriptase catalyses (A) Synthesis of RNA (B) Breakdown of RNA (C) Synthesis of DNA (D) Breakdown of DNA

Description : Reverse transcriptase catalyses (A) Synthesis of RNA (B) Breakdown of RNA (C) Synthesis of DNA (D) Breakdown of DNA

Last Answer : Answer : C

What is not True for DNA in prokaryotes a) present in the form of a compact structure called nucleoid b) the coils are maintained by non-histone basic proteins c) found in cytoplasm in a supercoiled condition d) packaged as nucleosomes along with histones

Description : What is not True for DNA in prokaryotes a) present in the form of a compact structure called nucleoid b) the coils are maintained by non-histone basic proteins c) found in cytoplasm in a supercoiled condition d) packaged as nucleosomes along with histones

Last Answer : b) the coils are maintained by non-histone basic proteins

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.

The hereditary material present in the bacterium E.coli is (a) single-stranded DNA (b) double-stranded DNA (c) DNA (d) RNA.

Description : The hereditary material present in the bacterium E.coli is (a) single-stranded DNA (b) double-stranded DNA (c) DNA (d) RNA.

Last Answer : (b) double-stranded DNA

The DNA of E.coli is (a) double stranded and linear (b) double stranded and circular (c) single stranded and linear (d) single stranded and circular.

Description : The DNA of E.coli is (a) double stranded and linear (b) double stranded and circular (c) single stranded and linear (d) single stranded and circular.

Last Answer : (b) double stranded and circular

The DNA of E.coli is (a) double stranded and linear (b) double stranded and circular (c) single stranded and linear (d) single stranded and circular.

Description : The DNA of E.coli is (a) double stranded and linear (b) double stranded and circular (c) single stranded and linear (d) single stranded and circular.

Last Answer : (b) double stranded and circular

Leguminous plants are able to fix atmospheric nitrogen through the process of symbiotic nitrogen fixation. Which one of the following statements is not correct during this process of nitrogen fixation? (a) Leghaemoglobin scavenges oxygen and is pinkish in colour. (b) Nodules act as sites for nitrogen fixation. (c) The enzyme nitrogenase catalyses the conversion of atmospheric N2 to NH3. (d) Nitrogenase is insensitive to oxygen.

Description : Leguminous plants are able to fix atmospheric nitrogen through the process of symbiotic nitrogen fixation. Which one of the following statements is not correct during this process of nitrogen fixation ... the conversion of atmospheric N2 to NH3. (d) Nitrogenase is insensitive to oxygen.

Last Answer : (d) Nitrogenase is insensitive to oxygen.

Do you think this ad positively or negatively affects this company?

Description : Do you think this ad positively or negatively affects this company?

Last Answer : Sort of hilarious, but not a good ad. I can’t say why. I guess I just don’t like the “in your face” ness of it.

When negatively charged colloids like `As_(2)S_(3)` sol is added to positively charged `Fe(OH)_(3)` sol in suitable amounts

Description : When negatively charged colloids like `As_(2)S_(3)` sol is added to positively charged `Fe(OH)_(3)` sol in suitable amounts

Last Answer : When negatively charged colloids like `As_(2)S_(3)` sol is added to positively charged `Fe ... colloids. D. They become negatively charged colloids.

Is human blood positively or negatively charged?

Description : Is human blood positively or negatively charged?

Last Answer : Neither, blood is neutral.It does contain both positively and negatively charged ions, butin equal amounts so that they cancel.

When water breaks apart it releases positively charged hydrogen ions and negatively charged ions?

Description : When water breaks apart it releases positively charged hydrogen ions and negatively charged ions?

Last Answer : Need answer

Total fixed cost curve is - (1) Vertical (2) Horizontal (3) Positively Sloping (4) Negatively sloping

Description : Total fixed cost curve is - (1) Vertical (2) Horizontal (3) Positively Sloping (4) Negatively sloping

Last Answer : (2) Horizontal Explanation: The Total Fixed Cost Curve is a curve that graphically represents the relation between total fixed cost incurred by a firm in the short-run product of a good or service and the ... cost are, in fact, fixed, the total fixed cost curve is, in fact, a horizontal line.

Under increasing returns the supply curve is - (1) positively sloped from is to right (2) negatively sloped from left to right (3) parallel to the quantity-axis (4) parallel to the price -axis

Description : Under increasing returns the supply curve is - (1) positively sloped from is to right (2) negatively sloped from left to right (3) parallel to the quantity-axis (4) parallel to the price -axis

Last Answer : (1) positively sloped from is to right Explanation: Supply curve, in economics, is a graphic representation of the relationship between product price and quantity of product that a seller is willing and ... i.e as the price of a commodity increases in the market, the amount supplied increases).

Demand curve of a firm under perfect competition is : (1) horizontal to ox-axis (2) negatively sloped (3) positively sloped (4) U - shaped

Description : Demand curve of a firm under perfect competition is : (1) horizontal to ox-axis (2) negatively sloped (3) positively sloped (4) U - shaped

Last Answer : (1) horizontal to ox-axis Explanation: Under Perfect Competition, the firm faces a horizontal demand curve. It can sell any quantity desired at the market price, but cannot sell anything above the market price.

Stern is usually - (1) Positively Phototropic (2) Negatively Phototropic (3) Negatively geotropic (4) Positively acrotropic

Description : Stern is usually - (1) Positively Phototropic (2) Negatively Phototropic (3) Negatively geotropic (4) Positively acrotropic

Last Answer : (1) Positively Phototropic Explanation: Tropism is a growth movement whose direction is determined by the direction from which the stimulus strikes the plant. Most stems are positively phototropic, while most roots are said to be negatively phototropic.

A good conductor while carrying current is - (1) alternately charged positive and negative (2) negatively charged (3) positively charged (4) electrically neutral

Description : A good conductor while carrying current is - (1) alternately charged positive and negative (2) negatively charged (3) positively charged (4) electrically neutral

Last Answer : (2) negatively charged Explanation: Electrons carry current in a good conductor of electricity and they are negatively charged. This makes a good electrical conductor negatively charged.

X-rays are – (1) positively charged particles (2) negatively charged particles (3) neutral particles (4) None of these

Description : X-rays are – (1) positively charged particles (2) negatively charged particles (3) neutral particles (4) None of these

Last Answer : (3) neutral particles Explanation: Like gamma rays and neutrons, X-rays are electrically neutral. They have neither a positive nor a negative charge. They cannot be accelerated or made to ... particles (electrons and positrons) and heavy charged particles (protons, alpha particles and heavier ions).

A wire carrying current is – (1) positively charged (2) negatively charged (3) neutral (4) charged with a type depending upon current strength

Description : A wire carrying current is – (1) positively charged (2) negatively charged (3) neutral (4) charged with a type depending upon current strength

Last Answer : (3) neutral

SnO2 forms a positively charged colloidal sol in acidic medium and a negatively charged sol in the basic medium. Why ?

Description : SnO2 forms a positively charged colloidal sol in acidic medium and a negatively charged sol in the basic medium. Why ? 

Last Answer : Ans. SnO2 is amphoteric in nature. It reacts with acid eg. HCl to form SnCl4 in the solution. The common Sn4+ ions are adsorbed on the surface of SnO2 particles giving them a positive ... solution. The stannate ions are adsorbed on the surface of SnO2 particles giving them a negative charge. 

When one material is rubbed against the other, then it becomes electrically A. neutral B. charged C. positively charged D. negatively charged

Description : When one material is rubbed against the other, then it becomes electrically A. neutral B. charged C. positively charged D. negatively charged

Last Answer : charged

Which of the following activates Hageman factor in blood clotting? B A. Kinins B. Negatively charged surfaces C. Complement C5a D. Positively charged collagen

Description : Which of the following activates Hageman factor in blood clotting? B A. Kinins B. Negatively charged surfaces C. Complement C5a D. Positively charged collagen

Last Answer : Negatively charged surfaces

Phosphorus and nitrogen ions generally get depleted in soil because they usually occur as (a) neutral ions (b) negatively charged ions (c) positively charged ions (d) both positively and negatively charged but disproportionate mixture.

Description : Phosphorus and nitrogen ions generally get depleted in soil because they usually occur as (a) neutral ions (b) negatively charged ions (c) positively charged ions (d) both positively and negatively charged but disproportionate mixture.

Last Answer : (b) negatively charged ions

Aerosols present in atmospheric air may be (A) Positively charged (B) Negatively charged (C) Neutral (D) Combination of all (A), (B) & (C)

Description : Aerosols present in atmospheric air may be (A) Positively charged (B) Negatively charged (C) Neutral (D) Combination of all (A), (B) & (C)

Last Answer : (D) Combination of all (A), (B) & (C)