Last Answer : answer:
Description : What are the components and structure of a DNA double helix molecule?
Last Answer : Feel Free to Answer
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 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 : Which best describes the structure of a DNA molecule?
Last Answer : The structure of a DNA molecule is generally called a "Double Helix"
Description : which best describes the structure of dna molecule?
Last Answer : Answer:Two strands of DNA link together
Description : Which best describes the structure of the DNA molecule?
Description : A single DNA molecule condensed into a compact structure in vivo by complexing with accessory histones or histone-like proteins.
Last Answer : Ans. Chromosome
Description : The figure below shows the structure of a mitochondrion with its four parts labelled A, B, C and D. Select the part correctly matched with its function. D B A C (a) D (outer ... possesses single circular DNA molecule and ribosomes (d) A (matrix) - major site for respiratory chain enzyme
Last Answer : (b) B (inner membrane) – forms infoldings called cristae
Description : Are both sides of the DNA helix used for the same amino acid?
Last Answer : Typically only one strand is used as the template for messenger RNA synthesis, but some regions of DNA can encode multiple RNAs that are transcribed from opposite strands.
Last Answer : Double helix discovers DNA (Watson and Creek)
Last Answer : Watson And Creek DNA Double Helix Model Discovery Does.
Description : In DNA helix, cytosine is paired with guanine by
Last Answer : In DNA helix, cytosine is paired with guanine by A. covalent bond B. phosphate bond C. three hydrogen bonds D. two hydrogen bonds
Description : $ DNA helix to 20Å wide. One complete turn of DNA is 34Å long.
Last Answer : $ DNA helix to 20Å wide. One complete turn of DNA is 34Å long. A. If both As and R are correct and R ... , R is wrong D. If both As and R are wrong.
Description : The outside of the DNA double helix is made of alternating groups of deoxyribose sugars and _____.?
Last Answer : phosphates
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 : 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 : 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 : 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 : Ten base pairs are present in one turn of the helix in (A) A-DNA (B) B-DNA (C) C-DNA (D) Z-DNA
Last Answer : Answer : B
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 : The width (helical diameter) of the double helix in B-form DNA in nm is (A) 1 (B) 2 (C) 3 (D) 4
Description : Mitochondrial DNA is (A) Circular double stranded (B) Circular single stranded (C) Linear double helix (D) None of these
Last Answer : A
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 : 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.
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 : 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
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 : 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 : 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 : 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 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 : 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
Description : What type of bonding helps in stabilishing the a-helix structure of proteins? -Chemistry
Last Answer : a-helix formation -» Intramolecular hydrogen bonding.
Description : The structure of tRNA appears like a (A) Helix (B) Hair pin (C) Clover leaf (D) Coil
Last Answer : Answer : C
Description : In protein structure the α-helix and βpleated sheets are example of (A) Primary structure (B) Secondary structure (C) Tertiary structure (D) Quaternary structure
Description : The a-helix of proteins is (A) A pleated structure (B) Made periodic by disulphide bridges (C) A non-periodic structure (D) Stabilised by hydrogen bonds between NH and CO groups of the main chain
Description : In proteins the α-helix and β-pleated sheet are examples of (A) Primary structure (B) Secondary structure (C) Tertiary structure (D) Quaternary structure
Description : What type of bonding helps in stabilising the -helix structure of proteins ?
Last Answer : Ans. In a -helix structure, polypeptide chain of amino acids coils as a right handed screw because of the formation of all possible Hydrogen bonds between — NH group at each amino residue and > C = 0 group of adjacent turn of helix.
Description : The α-Helix is a common form of (a) Primary structure (b) Tertiary structure (c) Secondary structure (d) None of these
Last Answer : Secondary structure
Description : The primary structure of a protein refers to : (a) whether the protein is fibrous or globular (b) the amino acid sequence in the polypeptide chain (c) the orientation of the amino acid side chains in space (d) the presence or absence of an α-helix
Last Answer : the amino acid sequence in the polypeptide chain
Description : Which of the following may characterize the “secondary structure” of proteins? (a) conformation of the protein backbone (b) α-Helix (c) parallel β-pleated sheet (d) all of the above
Last Answer : all of the above