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
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
Last Answer : (c) 2.2 meters
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 : 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 : One turn of the helix in a B-form DNA is approximately (a) 2 nm (b) 20 nm (c) 0.34 nm (d) 3.4 nm.
Last Answer : ) 3.4 nm.
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 : The distance travelled per turn of α-helix in nm is (A) 0.34 (B) 0.44 (C) 0.54 (D) 0.64
Last Answer : Answer : C
Description : Along the α-helix each amino acid residue advances in nm by (A) 0.15 (B) 0.10 (C) 0.12 (D) 0.20
Last Answer : Answer : A
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
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
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
Last Answer : Answer : B
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 : 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
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 : 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
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 : 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 : 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 : 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 : 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 : The first laser emitted a. Pulses of 694 nm red light b. A continuous red beam c. Pulses of white light from a helical flashlamp d. Spontaneous emission
Last Answer : a. Pulses of 694 nm red light
Description : The first laser emitted ∙ a. Pulses of 694 nm red light ∙ b. A continuous red beam ∙ c. Pulses of white light from a helical flash lamp ∙ d. Spontaneous emission
Last Answer : ∙ a. Pulses of 694 nm red light
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 : During replication, unwinding of double helix is initiated by (A) DNAA protein (B) DnaB protein (C) DNAC protein (D) Rep protein
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
Description : Proteins which interact with DNA and affect the rate of transcription possess the following structural motif: (A) Helix-turn-helix motif (B) Zinc finger motif (C) Leucine zipper motif (D) All of these
Description : Ten base pairs are present in one turn of the helix in (A) A-DNA (B) B-DNA (C) C-DNA (D) Z-DNA
Description : The distance spanned by one turn of Bform DNA is (A) 1.0 nm (B) 2.0 nm (C) 3.0 nm (D) 3.4 nm
Description : What is the spectral width of an ILD? ∙ A. 0.1 nm to 1 nm ∙ B. 2 nm to 5 nm ∙ C. 1 nm to 3 nm ∙ D. 3 nm to 4 nm
Last Answer : C. 1 nm to 3 nm
Description : What is the spectral width of a standard LED? ∙ A. 20 to 40 nm ∙ B. 30 to 50 nm ∙ C. 10 to 30 nm ∙ D. 40 to 60 nm
Last Answer : 30 to 50 nm
Description : Why are the two strands of the double helix described as being complementary?
Last Answer : Complementarity is the key to understand the stability of the double helix of DNA in the Watson-Crick model (the most stable among other conformations). DNA complementarity property is determined by ... close to unity for deoxyribose nucleic acid." (In perfect agreement with the Chargaff's rules)