Operon model of gene regulation and organisation of prokaryotes was proposed by: (a) Messelson and Stahl (b) Wilkins and Franklin (c) Beadle and Tatum (d) Jacob and Monod

1 Answer

Answer :

Ans. ((d))

Related questions

Description : Select the correct match. (a) Alec Jeffreys - Streptococcus pneumoniae (b) Alfred Hershey and - TMV Martha Chase (c) Matthew Meselson - Pisum sativum and F. Stahl (d) Francois Jacob and - Lac operon Jacques Monod

Last Answer : (a) Alec Jeffreys - Streptococcus pneumoniae

Description : Select the correct match. (a) Alec Jeffreys - Streptococcus pneumoniae (b) Alfred Hershey and - TMV Martha Chase (c) Matthew Meselson - Pisum sativum and F. Stahl (d) Francois Jacob and - Lac operon Jacques Monod

Last Answer : (d) Francois Jacob and - Lac operon Jacques Monod

Description : Select the correct match : (1) Alec Jeffreys – Streptococcus pneumoniae (2) Alfred Hershey and – TMV Martha Chase (3) Matthew Meselson – Pisum sativum and F. Stahl (4) Francois Jacob and – Lac operon Jacques Monod

Last Answer : (4) Francois Jacob and – Lac operon Jacques Monod

Description : One gene-one enzyme hypothesis was postulatedby (a) Beadle and Tatum (b) R. Franklin (c) Hershey and Chase (d) A. Garrod.

Last Answer : (c) Hershey and Chase

Description : One gene-one enzyme hypothesis was postulatedby (a) Beadle and Tatum (b) R. Franklin (c) Hershey and Chase (d) A. Garrod

Last Answer : (a) Beadle and Tatum

Description : Select the two correct statements out of the four (i - iv) statements given below about lac operon. (i) Glucose or galactose may bind with the repressor and inactivate it. (ii) In the absence of lactose, the repressor binds with the ... (iii) (b) (i) and (iii) (c) (ii) and (iv) (d) (i) and (ii)

Last Answer : (c) (ii) and (iv)

Description : That genes control heredity through their control on enzyme synthesis and that one gene controls the sythesis of one enzyme - the one gene one enzyme hypothesis — was proposed by (a) Beadle and Tatum (b) Darwin (c) Mendel (d) Morgan

Last Answer : Ans:(a)

Description : acob and Monod studied lactose metabolism in E. coli and proposed operon concept. Operon concept is applicable for (a) all prokaryotes (b) all prokaryotes and some eukaryotes (c) all prokaryotes and all eukaryotes (d) all prokaryotes and some protozoans

Last Answer : (c) all prokaryotes and all eukaryotes

Description : Whose experiments cracked the DNA and discovered unequivocally that a genetic code is a “triplet”? (a) Hershey and Chase (b) Morgan and Sturtevant (c) Beadle and Tatum (d) Nirenberg and Mathaei

Last Answer : (b) Morgan and Sturtevant

Description : Whose experiments cracked the DNA and discovered unequivocally that a genetic code is a “triplet”? (a) Hershey and Chase (b) Morgan and Sturtevant (c) Beadle and Tatum (d) Nirenberg and Mathaei

Last Answer : (b) Morgan and Sturtevant

Description : Reserve transcription was discovered by : (1) Beadle & Tatum (2) Waston & Crick (3) Temin & Baltimore (4) har Govind Khorana

Last Answer : Temin & Baltimore

Description : Chondriosome is discovered by: (a) Benda (b) Messelson (c) Dujardin (d) Taylor

Last Answer : Ans. ((a))

Description : Regulator gene controls chemical synthesis (Operon concept) by (a) Inhibiting transcription of mRNA (b) Inhibiting enzymes (c) Inhibiting passage of mRNA (d) Inhibiting substrate enzyme reaction

Last Answer : Ans. ((a))

Description : Which statement is true of rRNA? (a) Called soluble RNA (b) Named by Jacob and Monod (c) The smallest molecule of RNA (d) They form 80% of the total RNA

Last Answer : Ans:(d)

Description : .Gene regulation governing lactose operon of E.coli that involves the lac I gene product is (a) negative and repressible because repressor protein prevents transcription (b) feedback inhibition ... be induced by lactose (d) negative and inducible because repressor protein prevents transcription.

Last Answer : (d) negative and inducible because repressor protein prevents transcription.

Description : Gene regulation governing lactose operon of E.coli that involves the lac I gene product is (a) negative and repressible because repressor protein prevents transcription (b) feedback inhibition ... be induced by lactose (d) negative and inducible because repressor protein prevents transcription.

Last Answer : (d) negative and inducible because repressor protein prevents transcription.

Description : DNA mRNA C Proposed by Protein A B The figure gives an important concept in the genetic implication of DNA. Fill the blanks A, B and C. (a) A-Maurice Wilkins, B-Transcription, C-Translation ... c) A-Erwin Chargaff, B-Translation, C-Replication (d) A-Francis Crick, B-Translation, C-Transcription

Last Answer : (d) A-Francis Crick, B-Translation, C-Transcription

Description : Select the correct statement. (a) Franklin Stahl coined the term ‘‘linkage’’. (b) Punnett square was developed by a British scientist. (c) Spliceosomes take part in translation. (d) Transduction was discovered by S. Altman

Last Answer : (a) Franklin Stahl coined the term ‘‘linkage’’.

Description : Select the correct statement : (1) Franklin Stahl coined the term "linkage". (2) Punnett square was developed by a British scientist. (3) Spliceosomes take part in translation. (4) Transduction was discovered by S. Altman.

Last Answer : (2) Punnett square was developed by a British scientist.

Description : Who coined the term 'gene? (1) Mendel (2) Johannsen (3) Watson (4) Beadle

Last Answer : (2) Johannsen Explanation: Gene is a segment of DNA in all living organisms.

Description : Who coined the term ‘gene’ ? (1) Mendel (2) Johannsen (3) Watson (4) Beadle

Last Answer : Johannsen

Description : The term water potential was proposed by: (a) Godlewski (b) Slatyer and Taylor (c) Dixon and Jolly (d) J. C. Bose

Last Answer : Ans. ((b))

Description : Histogen theory was proposed by 

Last Answer : Histogen theory was proposed by – Hanstein

Description : Explain the law of segregation and law of independent assortment proposed by Mendel 

Last Answer : Ans: 1. Law of Segregation: This law shows that the two alleles of a gene when present together in a heterozygous state, do not fuse of blend in any way, but remain distinct and segregate ... factors, then the inheritance of one pair of factors is independent to that of other pair of factors.  

Description : A level of regulation, demonstrated by the termination of transcription if tryptophan is abundant, by the tryptophan operon in E.coli cells is called A.activation B.attenuation C.corepression D.desiccation

Last Answer : B.attenuation

Description : The Asokan Edicts were deciphered first by: (SSC CGL 2nd Sit. 2012) (a) Sir John Marshall (b) Sir William Jones (c) Charles Wilkins (d) James Princep

Last Answer : (d) James Princep

Description : The diagram shows an important concept in the genetic implication of DNA. Fill in the blanks A to C. DNA mRNA Proposed by Protein C A B (a) A - Transcription, B -Translation, C - Francis Crick (b) ... , B - Replication, C - James Watson (d) A - Translation, B - Transcription, C - Ervin Chargaff

Last Answer : (a) A - Transcription, B -Translation, C - Francis Crick

Description : The region of the Lac operon which must be free from structural gene transcription to occur is (A) The operator locus (B) The promoter site (C) The ‘a’ gene (D) The ‘i’ gene

Last Answer : Answer : A

Description : Which of the following genes of the E.coli “Lac operon” codes for a constitutive protein? (A) The ‘a’ gene (B) The ‘i’ gene (C) The ‘c’ gene (D) The ‘z’ gene

Last Answer : Answer : B

Description : The coding sequences in lac operon include (A) i gene (B) i gene, operator locus and promoter (C) z, y and a genes (D) i, z, y and a genes

Last Answer : Answer : D

Description : Lactose or its analogues act as positive regulators of lac operon by (A) Attaching to i gene and preventing its expression (B) Increasing the synthesis of catabolite gene activator protein (C) ... holoenzyme (D) Binding to repressor subunits so that the repressor cannot attach to the operator locus

Last Answer : Answer : D

Description : Binding of RNA polymerase holoenzyme to the promoter region of lac operon is facilitated by (A) Catabolite gene activator protein (CAP) (B) cAMP (C) CAP-cAMP complex (D) None of these

Last Answer : Answer : C

Description : The enzymes encoded by z, y and a genes of lac operon are inducible, and their inducer is (A) Lactose (B) Allo-lactose (C) Catabolite gene activator protein (D) All of these

Last Answer : Answer : B

Description : Transcription of structural genes of lac operon is prevented by binding of the repressor tetramer to (A) i gene (B) Operator locus (C) Promoter (D) z gene

Last Answer : Answer : B

Description : RNA polymerase holoenzyme binds to lac operon at the following site: (A) i gene (B) z gene (C) Operator locus (D) Promoter region

Last Answer : Answer : D

Description : The regulatory i gene of lac operon (A) Is inhibited by lacotse (B) Is inhibited by its own product, the repressor protein (C) Forms a regulatory protein which increases the expression of downstream structural genes (D) Is constitutively expressed

Last Answer : Answer : D

Description : Lac operon is a cluster of (A) Three structural genes (B) Three structural genes and their promoter (C) A regulatory gene, an operator and a promoter (D) A regulatory gene, an operator, a promoter and three structural genes

Last Answer : Answer : D

Description : The gene of lac operon which has constitutive expression is (A) i (B) c (C) z (D) p

Last Answer : Answer : A

Description : The smallest unit of DNA capable of coding for the synthesis of a polypeptide is (A) Operon (B) Repressor gene (C) Cistron (D) Replicon

Last Answer : Answer : C

Description : Match the following genes of the Lac operon with their respective products. (A) i gene (i) b-galactosidase (B) z gene (ii) Permease (C) a gene (iii)Repressor (D) y gene (iv) Transacetylase Select the correct option. (A) (B) (C) ( ... ) (iii) (ii) (iv) (c) (iii) (i) (ii) (iv) (d) (iii) (i) (iv) (ii)

Last Answer : (a) (iii) (iv) (i) (ii)

Description : The equivalent of a structural gene is (a) muton (b) cistron (c) operon (d) recon.

Last Answer : (a) muton

Description : Lac operon’ in E. coli, is induced by (a) ‘I’ gene (b) promoter gene (c) β-galactosidase (d) lactose.

Last Answer : (c) β-galactosidase

Description : In operon concept, regulator gene functions as (a) inhibitor (b) repressor (c) regulator (d) all of these.

Last Answer : a) inhibitor

Description : .E.coli cells with a mutated z gene of the lac operon cannot grow in medium containing only lactose as the source of energy because (a) the lac operon is constitutively active in these cells ( ... coli cells do not utilise lactose (d) they cannot transport lactose from the medium into the cell.

Last Answer : (b) they cannot synthesise functional beta galactosidase

Description : .The lac operon consists of (a) four regulatory genes only (b) one regulatory gene and three structural genes (c) two regulatory genes and two structural genes (d) three regulatory genes and three structural genes.

Last Answer : (b) one regulatory gene and three structural genes

Description : Match the following genes of the Lac operon with their respective products. (A) i gene (i) b-galactosidase (B) z gene (ii) Permease (C) a gene (iii)Repressor (D) y gene (iv) Transacetylase Select the correct option. (A) (B) (C) ( ... ) (iii) (ii) (iv) (c) (iii) (i) (ii) (iv) (d) (iii) (i) (iv) (ii)

Last Answer : d) (iii) (i) (iv) (ii)

Description : Which one of the following is NOT part of an operon? a. Regulatory gene b. Operator c. Promoter d. Structural genes

Last Answer : d. Structural genes

Description : The ribosome binding site A- forms a stem-loop structure in the RNA B- is located upstream of the promoter sequence C- .is located immediately upstream of the start codon D- is more likely to be associated with an operon than with a gene encoding a single protein

Last Answer : .is located immediately upstream of the start codon

Description : The rivosome binding site A- forms a sltem- loop structure in the RNA B- is located upstream of the promoter sequence C- is located immediately upstream of the start codon D- is more likely to be associated with an operon than with a gene encoding a single protein

Last Answer : is located immediately upstream of the start codon

Description : The ribosome binding site A- forms a stem-loop structure in the RNA B- is located upstream of the promoter sequence C- .is located immediately upstream of the start codon D- is more likely to be associated with an operon than with a gene encoding a single protein

Last Answer : .is located immediately upstream of the start codon