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
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
Description : DNA po lymerase of T. aquat icus is preferred to that of E. coli in PCR because (A) It replicates DNA more efficiently (B) It doesn’t require primers (C) It is not denatured at the melting temperature of DNA (D) It doesn’t cause errors in replication
Last Answer : Answer : C
Description : What is the genetic material in influenza virus? (a) Double helical DNA (b) RNA (c) Single helix DNA (d) None of these
Last Answer : (b) RNA
Description : The structure of DNA is a double helix formed by two strands of DNA sequence. This sequence consists of 4 different nucleotides- Adenine, Thymine, Cytosine and Guanine. How do the nucleotides on one strand interact with the nucleotides on the second strand to maintain the helical shape of DNA?
Last Answer : Complementary Base Pairing. Adenine complementary base pairs with Thymine and Guanine complementary base pairs with Cytosine.
Description : Stem and loop structures are A- proteins that help partially denatured enzymes to recover their native configuration B- structures in DNA caused by inverted repeats C- structures at the ends of linear eukaryotic DNA molecules D- the bonds between adjacent DNA nucleotides in the same strand
Last Answer : structures in DNA caused by inverted repeats
Description : The helix angle for double helical gears may be made up to (A) 45° (B) 60° (C) 75° (D) 90°
Last Answer : (A) 45°
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
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
Description : Left handed double helix is present in (A) Z-DNA (B) A-DNA (C) B-DNA (D) None of these
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
Description : Mitochondrial DNA is (A) Circular double stranded (B) Circular single stranded (C) Linear double helix (D) None of these
Last Answer : A
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
Description : Double helical structure model of the DNA was proposed by (A) Pauling and Corey (B) Peter Mitchell (C) Watson and Crick (D) King and Wooten
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
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
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
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.
Description : With regard to DNA molecules: a. they contain adenine, cytosine, guanine and uracil bases b. they can be detected with Western blotting c. they can be detected with Southern blotting d. they are denatured at temperature of 1000C
Last Answer : they can be detected with Southern blotting
Last Answer : Double helix discovers DNA (Watson and Creek)
Last Answer : Watson And Creek DNA Double Helix Model Discovery Does.
Description : What are the components and structure of a DNA double helix molecule?
Last Answer : Feel Free to Answer
Description : The outside of the DNA double helix is made of alternating groups of deoxyribose sugars and _____.?
Last Answer : phosphates
Description : The double helix model of DNA proposed by
Last Answer : Ans. Watson and Crick (1953)
Description : Double helix model of DNA was proposed by
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
Description : The two strands of the DNA double helix are held together by (a) Hydrogen bonds (b)C=C double bonds (c) Hydrophobic bonds (d) Peptide bonds
Last Answer : Ans:(a)
Description : If the distance between two consecutive base pairs is 0.34 nm and the total number of base pairs of a DNA double helix in a typical mammalian cell is 6.6 × 109 bp, then the length of the DNA is approximately (a) 2.0 meters (b) 2.5 meters (c) 2.2 meters (d) 2.7 meters.
Last Answer : (b) 2.5 meters
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
Last Answer : (c) 2.2 meters
Description : Radiotracer technique shows that DNA is in (a) multi-helix stage (b) single-helix stage (c) double-helix stage (d) none of these.
Last Answer : (c) double-helix stage
Description : In double helix of DNA, the two DNA strands are (a) coiled around a common axis (b) coiled around each other (c) coiled differently (d) coiled over protein sheath.
Last Answer : (a) coiled around a common axis
Description : Which is wrong about nucleic acids? (a) DNA is single stranded in some viruses. (b) RNA is double stranded occasionally. (c) Length of one helix is 45 Å in B-DNA. (d) One turn of Z-DNA has 12 bases
Last Answer : (c) Length of one helix is 45 Å in B-DNA
Description : The double helix is a structural arrangement associated with _____. a. A Polysaccharide. b. The DNA Molecule. c. Glucose Molecules In Starch. d. A Protein.
Last Answer : b. The DNA Molecule.
Description : A concentric spring consist of two helical compression springs (A) both springs always have right hand helix (B) both springs always have left hand helix (C) both springs always have opposite hand of helices (D) any of the above
Last Answer : (C) both springs always have opposite hand of helices
Description : The helix angle in case of closely coiled helical spring is (A) less than 5° (B) 5° to 7° (C) 7° to 10° (D) more than 10°
Last Answer : (D) more than 10°
Description : The helix angle in case of closely coiled helical spring is (A) less than 10° (B) 10° to 15° (C) 15° to 20° (D) more than 20°
Last Answer : (A) less than 10°
Description : Pick up the correct statement from the following: (A) A wire wound in spiral form, is called a helical spring (B) The pitch of a close coil spring, is very small (C) The angle made by the coil with horizontal, is called the angle of helix (D) All the above
Last Answer : (D) All the above
Description : A close coil helical spring when subjected to a moment M having its axis along the axis of the helix (A) It is subjected to pure bending (B) Its mean diameter will decrease (C) Its number of coils will increase (D) All the above
Last Answer : (A) It is subjected to pure bending
Description : 1.7 m double helical DNA will have base pairs
Last Answer : 1.7 m double helical DNA will have base pairs A. `3.4xx10^(9)` B. `5xx10^(9)` C. `1.7xx10^(9)` D. `1.7xx10^(5)`
Description : Which is not consistent with double helical structure of DNA? (a) A = T, C = G (b) Density of DNA decreases on heating. (c) A + T/C + G is not constant. (d) Both (a) and (b)
Last Answer : (c) A + T/C + G is not constant
Description : The double helical structure of DNA is held together by (a) sulfur-sulfur linkages (b) peptide bonding (c) hydrogen bonding (d) glycosidic bonds
Last Answer : hydrogen bonding
Description : What term refers to the heat needed to change a unit mass of a substance at its melting temperature from a solid into a liquid?
Last Answer : ANSWER: HEAT OF FUSION or LATENT HEAT OF FUSION or ENTHALPY OF FUSION
Description : The surface of water in a pond remains cool even on a hot day because 1. water evaporates at the surface and evaporation causes cooling 2. the heat absorbed at the surface is transmitted downwards 3. Water in contact with the bottom ... /are correct? (a) 1 only (b) 3 only (c) 1 and 3 (d) 1, 2 and 3
Description : Explain why o-hydroxybenzaldehyde is a liquid at room temperature while p-hydroxybenzaldehyde is a high melting solid.
Last Answer : Due to interamolecular H-bonding ortho-hydroxy benzaldehyde exists as discrete molecule whereas due to intermolecular H-bonding, p-hydroxybenzaldehyde exists as associated molecules. To break these intermolecular ... a liquid at room temperature while p-hydroxy benzaldehyde is a high melting solid.
Description : Solid and liquid phases of a substance are in equilibrium at the (A) Critical temperature (B) Melting point (C) Freezing point (D) Both (B) and (C)
Last Answer : D) Both (B) and (C)
Description : During replication, unwinding of double helix is initiated by (A) DNAA protein (B) DnaB protein (C) DNAC protein (D) Rep protein
Description : Would you expect the denatured DNA to regain its transforming capacity when cooled?
Last Answer : This sounds like a homework question.
Description : This compound has a double helical structure. (A) Deoxyribonucleic acid (B) RNA (C) Flavine-adevine dinucleotide (D) Nicotinamide adamine dinucleotide
Description : In RNA molecule guanine content does not necessarily equal its cytosine content nor does its adenine content necessarily equal its uracil content since it is a (A) Single strand molecule ( ... stranded molecule (C) Double stranded helical molecule (D) Polymer of purine and pyrimidine ribonucleotides