Description : Which of the following molecule catalyzes the transpeptidation reaction? A- RNA Polymerase B- Peptidlytransferase C- DNA ligase D- DNA polymerase
Last Answer : Peptidlytransferase
Description : Which of the following molecule catalyzes the transpeptidation reaction? A- RNA polymerase B- .Peptidyltransferase C- DNA ligase D- .DNA polymerase
Last Answer : .Peptidyltransferase
Description : The α-amino group of the new amino acyl tRNA in the A site carries out a nucleophilic attack on the esterified carboxyl group of the peptidyl tRNA occupying the P site. This reaction is catalysed by (A) DNA polymerase (B) RNA polymerase (C) Peptidyl transferase (D) DNA ligase
Last Answer : Answer : C
Description : A seals sticky ends of recombinant DNA segments. a. DNA Ligase b. restriction endonuclease c. protease d. RNA polymerase
Last Answer : b. restriction endonuclease
Description : At a chromosome replication fork, the lagging strand consists of__ That is joined by___. a. RNA sequences; DNA ligase b. Okazaki Fragments; RNA Polymerase c. RNA sequences; ribosomes d. Okazaki fragments; DNA ligase
Last Answer : d. Okazaki fragments; DNA ligase
Description : The enzyme adds complementary bases to the DNA template strand during replication. a. Ligase b. Helicase c. DNA polymerase III d. RNA polymerase
Last Answer : d. RNA polymerase
Description : One of the first enzymes synthesized by many bacteriophage is __________ , an RNA dependent RNA polymerase A.RNA transcriptase B.RNA polymerase C.RNA ligase D.RNA replicase
Last Answer : D.RNA replicase
Description : DNA-dependent RNA polymerase catalyzes transcription on one strand of the DNA which is called the
Last Answer : DNA-dependent RNA polymerase catalyzes transcription on one strand of the DNA which is called the ... Antistrand C. Template strand D. Coding strand
Description : Which of the following are examples of repair mechanisms in cells? a. mismatch repair b. excision repair c. DNA polymerase d. DNA ligase e. all are important in fixing mutations
Last Answer : e. all are important in fixing mutations
Description : The mechanism of antibacterial action of tetracycline involves (a) Binding to a component of the 50S ribosomal subunit (b) Inhibition of translocase activity (c) Blockade of binding of ... (d) Selective inhibition of ribosomal peptidyl transferases (e) Inhibition of DNA-dependent RNA polymerase
Last Answer : Ans: C
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 : Restriction endonucleases are enzymes which (a) make cuts at specific positions within the DNA molecule (b) recognize a specific nucleotide sequence for binding of DNA ligase (c) restrict the action of the enzyme DNA polymerase (d) remove nucleotides from the ends of the DNA molecule
Last Answer : (a) make cuts at specific positions within the DNA molecule
Description : Peptidyl transferase activity is located in (A) Elongation factor (B) A charged tRNA molecule (C) Ribosomal protein (D) A soluble cytosolic protein
Description : Which binding is inhibited by pactamycin? A- Aminoacyl-tRNA to the A-site of 30S subunit B- Initiator-tRNA to 30S/40S initiation complexes C- Peptidyl t-RNA to the 50S subunit D- Formation of peptide bond in P site
Last Answer : Initiator-tRNA to 30S/40S initiation complexes
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 : The role of molecular chaperones is to A-facilitate binding of ribosomes to mRNA B-degrade newly synthesized polypeptides that contain inaccurate sequences C-.facilitate binding of RNA polymerase to DNA D-aid a newly synthesized polypeptide in folding to its proper shape
Last Answer : -aid a newly synthesized polypeptide in folding to its proper shape
Last Answer : aid a newly synthesized polypeptide in folding to its proper shape
Description : In prokaryotes, chloramphenicol (A) Causes premature release of the polypeptide chain (B) Causes misreading of the mRNA (C) Depolymerises DNA (D) Inhibits peptidyl transferase activity
Last Answer : Answer : A
Description : An important method used in the rapid identification of a pathogen is a. RNA gene sequencing b. polymerase chain reaction c. molecular taxonomy d. biochemical tests
Last Answer : d. biochemical tests
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 : Which of the following reunites the exon segments after RNA splicing? (a) RNA polymerase (b) RNA primase (c) RNA ligase (d) RNA proteose
Last Answer : a) RNA polymerase
Description : Which of the following reunites the exon segments after RNA splicing? (a) RNA polymerase (b) RNA primase (c) RNA ligase (d) RNA proteoses
Last Answer : (c) RNA ligase
Description : Which of the following step of translation does not consume a high energy phosphate bond? (a) Peptidyl transferase reaction (b) Aminoacyl tRNA binding to A-site (c) Translocation (d) Amino acid activation
Last Answer : (b) Aminoacyl tRNA binding to A-site
Last Answer : (a) Peptidyl transferase reaction
Description : Xeroderma pigmentosum results from a defect in (A) uvr ABC excinuclease (B) DNA polymerase I (C) DNA ligase (D) All of these
Description : Damage to DNA caused by ultraviolet radiation can be repaired by (A) uvr ABC excinuclease (B) DNA polymerase I (C) DNA ligase (D) All of these
Last Answer : Answer : D
Description : Negative supercoils are introduced in DNA by (A) Helicase (B) DNA ligase (C) DNA gyrase (D) DNA polymerase III holoenzyme
Description : DNA fragments are sealed by (A) DNA polymerase II (B) DNA ligase (C) DNA gyrase (D) DNA topoisomerase II
Last Answer : Answer : B
Description : In DNA replication the enzyme required in the first step is (A) DNA directed polymerase (B) Unwinding proteins (C) DNA polymerase (D) DNA ligase
Description : Which of the following enzymes are used to join bits of DNA? (a) Ligase (b) Primase (c) DNA polymerase (d) Endonuclease
Last Answer : a) Ligase
Description : The linking of antibiotic resistance gene with the plasmid vector became possible with (a) DNA polymerase (b) exonucleases (c) DNA ligase (d) endonucleases.
Last Answer : (c) DNA ligase
Description : A foreign DNA and plasmid cut by the same restriction endonuclease can be joined to form a recombinant plasmid using (a) EcoRI (b) Taq polymerase (c) polymerase III (d) ligase.
Last Answer : (d) ligase.
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 : Erythromycin binds to 50 S ribosomal sub unit and (A) Inhibits binding of amino acyl tRNA (B) Inhibits Peptidyl transferase activity (C) Inhibits translocation (D) Causes premature chain termination
Description : Peptidyl transferase activity of 50 S ribosomal subunits is inhibited by (A) Rifampicin (B) Cycloheximide (C) Chloramphenicol (D) Erythromycin
Description : After formation of a peptide bond, mRNA is translocated along the ribosome by (A) eEF-1 and GTP (B) eEF-2 and GTP (C) Peptidyl transferase and GTP (D) Peptidyl transferase and ATP
Description : Peptidyl transferase activity is present in (A) 40 S ribosomal subunit (B) 60 S ribosomal subunit (C) eEF-2 (D) Amino acyl tRNA
Description : Erythromycin acts on ribosomes and inhibit (A) Formation of initiation complex (B) Binding of aminoacyl tRNA (C) Peptidyl transferase activity (D) Translocation
Description : Streptomycin prevents synthesis of polypeptide by (A) Inhibiting initiation process (B) Releasing premature polypeptide (C) Inhibiting peptidyl transferase activity (D) Inhibiting translocation
Description : Translocation of the newly formed peptidyl tRNA at the A site into the empty P site involves (A) EF-II, GTP (B) EF-I, GTP (C) EF-I, GDP (D) Peptidyl transferase, GTP
Description : Peptidyl transferase a) Is a 23s rRNA b) forms peptide bonds c) component of ribosome d) all the three
Last Answer : d) all the three
Description : Template-directed DNA synthesis occurs in all the following except (A) The replication fork (B) Polymerase chain reaction (C) Growth of RNA tumor viruses (D) Expression of oncogenes
Description : Template-directed DNA synthesis occurs in all the following except (A) The replication fork (B) Polymerase chain reaction (C) Growth of RNA tumor viruses (D) Expression of oneogenes
Description : The following statement(s) is/are true concerning newer detection methods of systemic infection. a. Enzyme-linked immunosorbent assay (ELISA) is a rapid immunologic assay used for ... detected using advanced molecular techniques include cytomegalovirus (CMV) and human immunodeficiency virus (HIV)
Last Answer : Answer: a, b, c, d Although the classic detection of infection based on clinical signs of infection and bacterial culture remain the most common clinical tools, increasing ... including CMV and HIV. Furthermore, preliminary investigations into possible detection of fungal pathogens are underway
Description : In the metabolic pathway, ABCDE, discuss what effect molecule E would likely have on regulating the enzyme that catalyzes the reaction of A to B?
Last Answer : E is the product. If there is enough of molecule E to complete a chemical process, for example, the molecules (reactants) ABCDE will not be needed, and therefore an excess of E means less of ABCDE produced.
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 : Ceruloplasmin shows the activity (A) As ferroxidase (B) As reductase (C) As ligase (D) As transferase
Description : The enzyme hexokinase is a (A) Hydrolase (B) Oxidoreductase (C) Transferase (D) Ligase