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
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 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 : Given below is a sample of a portion of DNA strand giving the base sequence on the opposite strands. What is so special shown in it? 5′ _____ GAATTC _____ 3′ 3′ _____ CTTAAG _____ 5′ (a) ... completed (b) Deletion mutation (c) Start codon at the 5′ end (d) Palindromic sequence of base pairs
Last Answer : (d) Palindromic sequence of base pairs
Description : Following statements describe the characteristics of the enzyme restriction endonuclease. Identify the incorrect statement. (a) The enzyme recognises a specific palindromic nucleotide sequence in the DNA. (b) ... (d) The enzyme cuts the sugar-phosphate backbone at specific sites on each strand.
Last Answer : (c) The enzyme binds DNA at specific sites and cuts only one of the two strands.
Description : Antiparallel strands of a DNA molecule means that (a) one strand turns clockwise (b) one strand turns anti-clockwise (c) the phosphate groups of two DNA strands, at their ends, share the same position (d) the phosphate groups at the start of two DNA strands are in opposite position (pole).
Last Answer : (d) the phosphate groups at the start of two DNA strands are in opposite position (pole).
Description : In the semiconservative method of replication a. Both parent strands are degraded. b. One parent strand is conserved in each of the the new dna. c. Both parent strands reform with one another. d. Okazaki fragments form both of the new molecules of DNA.
Last Answer : b. One parent strand is conserved in each of the the new dna.
Description : Alkylating agents exert cytotoxic action by inducing: A. Breakage of DNA strand B. Cross linking of DNA strands C. Abnormal pairing of purine and pyrimidine bases D. All of the above
Last Answer : D. All of the above
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 : During replication, the template DNA is unwound (A) At one of the ends (B) At both the ends (C) At multiple sites (D) Nowhere
Last Answer : Answer : C
Description : After formation of replication fork (A) Both the new strands are synthesized discontinuously (B) One strand is synthesized continuously and the other discontinuously (C) Both the new strands are synthesized continuously (D) RNA primer is required only for the synthesis of one new 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
Description : In sticky ends produced by restriction endonucleases (A) The 2 strands of DNA are joined to each other (B) The DNA strands stick to the restriction endonuclease (C) The ends of a double stranded fragment are overlapping (D) The ends of a double stranded fragment are non overlapping
Description : Termination of the synthesis of the RNA molecule is signaled by a sequence in the template strand of the DNA molecule, a signal that is recognized by a termination protein, the (A) Rho (ρ) factor (B) σ factor (C) δ factor (D) ε factor
Last Answer : Answer : A
Description : In prestressing work, if more than one wire or strand is included in the same duct, why should all wires/strands be stressed at the same time?
Last Answer : If wires/strands are stressed individually inside the same duct, then those stressed strand/wires will bear against those unstressed ones and trap them. Therefore, the friction of the trapped wires is high and is undesirable.
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 : During transcription, do both strands of DNA get transcribed into a double stranded RNA molecule?
Last Answer : No. RNA is single stranded and is transcribed from only one of the DNA strands. DNA replication does make copies of both strands.
Description : Restriction endonucleases recognize and cut a certain sequence of (A) Single stranded DNA (B) Double stranded DNA (C) RNA (D) Protein
Description : Answer: a, b, c, d Free oxygen radicals are chemical species that are intermediates in the normal process of cellular respiration. Oxidants that are free radicals have been implicated as initiators of ... a. C-reactive protein b. Serum amyloid c. a -Proteinase inhibitor d. Fibrinogen e. Albumin
Last Answer : Answer: a, b, c, d The acute-phase response is a series of homeostatic responses of the organism to tissue injury in infection and inflammation. After an inflammatory stimulus occurs, a number ... 30% to 50% of the level before injury. The reason for the decrease in production is poorly understood
Description : What is a segment of a DNA strand that contains information for a single task or trait called?
Last Answer : Need answer
Description : Choose the correct statement about topotecan: A. It is a DNA topoisomerase I inhibitor which causes single strand DNA breaks B. It is a cell cycle specific anticancer drug C. It is a COMT-inhibitor used in advanced parkinsonism D. Both 'A' and 'B' are correc
Last Answer : D. Both 'A' and 'B' are correct
Description : Human immuno deficiency virus (HIV) has a protein coat and a genetic material which is (a) double stranded RNA (b) double stranded DNA (c) single stranded DNA (d) single stranded RNA
Last Answer : (d) single stranded RNA.
Description : The locus of a point on a thread unwound from a cylinder will be a.A circle b.A cycloid c.A straight line d.A spiral e.An involute
Last Answer : b. A cycloid
Description : mRNA is complementary copy of (A) 5′-3′ strand of DNA+ (B) 3′-5′ strand of DNA (C) Antisense strand of DNA (D) tRNA
Description : Anticodon sequence are seen in (A) tRNA and transcribed DNA strand (B) tRNA and complementary DNA strand (C) mRNA (D) mRNA and complementary DNA strand
Description : Codons are present on (A) Non-coding strand of DNA (B) hnRNA (C) tRNA (D) None of these
Description : Anticodons are present on (A) Coding strand of DNA (B) mRNA (C) tRNA (D) rRNA
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
Description : Codons are present in (A) Template strand of DNA (B) mRNA (C) tRNA (D) rRNA
Description : Ultraviolet light can damage a DNA strand causing (A) Two adjacent purine residue to form a covalently bounded dimer (B) Two adjacent pyrimidine residues to form covalently bonded dimer (C) Disruption of phosphodiesterase linkage (D) Disruption of non-covalent linkage
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)
Description : Most hormone receptors are localized on the cell membrane and transduce hormone binding into altered levels of intracellular messengers. A limited number of intracellular receptors do exist. Which of ... protein serves as an inhibitor protein blocking the DNA-binding domain of the steroid receptor
Last Answer : Answer: a, d Although most hormone and other messenger receptors are extracellular, intracellular receptors have been identified. The hormone messengers involved for these receptors are primarily ... DNA-binding domain of the receptor. Activation involves the dissociation of the inhibitor protein
Description : Negative regulation of protein synthesis is accomplished by A- allosteric inhibition B- the binding of RNA polymerase to the promoter C- the binding of a repressor to the DNA D- the binding of a repressor to the RNA polymerase
Last Answer : the binding of a repressor to the DNA
Description : What is the characteristic impedance of a single wire with a diameter d= 0.25 mm placed at the center between grounded parallel planes separated by 1 mm apart. The wire is held by a material with a velocity factor of 0.75. A. 85 Ω B. 63 Ω C. 50 Ω D. 75 Ω
Last Answer : D. 75 Ω
Description : What are coiled protein strands that have barbs tipped with poisin called?
Description : RNA is composed of strands of nucleotides that are read as a 3 nucleotide codon. These are distinguished by tRNAs that match the codons on one end and carry individual building blocks of a protein chain. What are these building blocks of protein that tRNAs bind?
Last Answer : Amino Acids
Description : $ The two strands of DNA run in an antiparallel directions DNA is formed of Deoxyribose sugar. Phosphorus and nitrogen bases called purines and pyrimi
Last Answer : $ The two strands of DNA run in an antiparallel directions DNA is formed of Deoxyribose sugar. Phosphorus and ... wrong D. If both As and R are wrong.
Description : In a cell the tangled long strands of DNA form the?
Last Answer : In a cell, the tangles of long strands of DNA form the
Description : What is long uncoiled strands of DNA in animal cell?
Description : Which of the following statement(s) is/are true concerning DNA? a. DNA is contained only in the nucleus of the cell b. DNA strands are encoded by the sequence of four bases-adenine, guanine, cytosine ... DNA is the intron, a sequence of three bases d. There are an infinite number of possible codons
Last Answer : Answer: a The genetic blueprint of an organism is carried in the nucleus of every cell, encoded by the sequence of four bases-adenine, guanine, cytosine and thymine, which together make up ... codons. Sixty-one of these code for amino acids and three are termination signals called stop codons
Description : Give reason: The two strands of DNA molecule are complementary to each other but are not identical.
Last Answer : The two strands of DNA are not identical because the nitrogenous bases are different in pairing. A purine base of one polynucleotide chain always pairs with a pyramidine base on the other. Adenine (A) pairs ... and Cytosine (C) pairs with Thymine (T). Hence the two strands of DNA are complementary.
Description : The figure below shows three steps (A, B, C) of Polymerase Chain Reaction (PCR). Select the option giving correct identification together with what it represents? A. B. C ds DNA 3 5 5 3 ... - extension in the presence of heat stable DNA polymerase (d) A - annealing with two sets of primers
Last Answer : (c) C - extension in the presence of heat stable DNA polymerase
Description : Choose the correct pair from the following. (a) Ligases - Join the two DNA molecules (b) Polymerases - Break the DNA into fragments (c) Nucleases - Separate the two strands of DNA (d) Exonucleases - Make cuts at specific positions within DNA
Last Answer : (a) Ligases - Join the two DNA molecules
Description : During DNA replication, the strands separate by (a) DNA polymerase (b) topoisomerase (c) unwindase/helicase (d) gyrase.
Last Answer : b) topoisomerase
Description : Method of DNA replication in which two strands of DNA separate and synthesise new strands is called (a) dispersive (b) conservative (c) semi-conservative (d) non conservative
Last Answer : (a) dispersive
Description : Escherichia coli fully labelled with 15N is allowed to grow in 14N medium. The two strands of DNA molecule of the first generation bacteria have (a) different density and do not resemble parent DNA ( ... DNA (c) same density and resemble parent DNA (d) same density but do not resemble parent DNA.
Last Answer : (c) same density and resemble parent DNA
Last Answer : (a) different density and do not resemble parent DNA
Description : n the DNA molecule, (a) the proportion of adenine in relation to thymine varies with the organism (b) there are two strands which run anti- parallel-one in 5′ → 3′ direction and other in 3′ → ... is not always equal (d) there are two strands which run parallel in the 5′ → 3′ direction.
Last Answer : (b) there are two strands which run anti- parallel-one in 5′ → 3′ direction and other in 3′ → 5′
Description : The main difference between a self-transmissible and a mobilizableplasmidis that the selftransmissible plasmid A- transfers both strands of the plasmid DNA B- carries genes encoding the mating apparatus C- transfers antibiotic resistance genes D- usually has a transposon inserted into it
Last Answer : carries genes encoding the mating apparatus