What does “lac” refer to in what we call the lac operon? (a) Lactose (b) Lactase (c) Lac insect (d) The number 1,00,000

What does “lac” refer to in what we call the lac operon?
(a) Lactose (b) Lactase
(c) Lac insect (d) The number 1,00,000
by

1 Answer

Answer :

(a) Lactose
by

Related questions

In lac operon, lactose acts are

Description : In lac operon, lactose acts are

Last Answer : In lac operon, lactose acts are A. Inducer B. Co-inducer C. Repressor D. Co-repressor

Expression of structural genes of lac operon is affected by all the following except (A) Lactose or its analogues (B) Repressor tetramer (C) cAMP (D) CAP-cAMP complex

Description : Expression of structural genes of lac operon is affected by all the following except (A) Lactose or its analogues (B) Repressor tetramer (C) cAMP (D) CAP-cAMP complex

Last Answer : Answer : C

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) Attaching to promoter region and facilitating the binding of RNA polymerase holoenzyme (D) Binding to repressor subunits so that the repressor cannot attach to the operator locus

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

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

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

Trancription of z, y and a genes of lac operon is prevented by (A) Lactose (B) Allo-lactose (C) Repressor (D) cAMP

Description : Trancription of z, y and a genes of lac operon is prevented by (A) Lactose (B) Allo-lactose (C) Repressor (D) cAMP

Last Answer : Answer : C

.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 because excess of β-galactosidase can switch off transcription (c) positive and inducible because it can be induced by lactose (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.

Which of the following is required as inducer(s) for the expression of Lac operon? (a) Lactose (b) Lactose and galactose (c) Glucose (d) Galactose

Description : Which of the following is required as inducer(s) for the expression of Lac operon? (a) Lactose (b) Lactose and galactose (c) Glucose (d) Galactose

Last Answer : (c) Glucose

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

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

The wild type E.coli cells are growing in normal medium with glucose. They are transferred to a medium containing only lactose as sugar. Which of the following changes take place? (a) The lac operon is induced. (b) E.coli cells stop dividing. (c) The lac operon is repressed. (d) All operons are induced.

Description : The wild type E.coli cells are growing in normal medium with glucose. They are transferred to a medium containing only lactose as sugar. Which of the following changes take place? (a) The lac operon is ... ) E.coli cells stop dividing. (c) The lac operon is repressed. (d) All operons are induced.

Last Answer : (a) The lac operon is induced

.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 (b) they cannot synthesise functional beta galactosidase (c) in the presence of glucose, E.coli cells do not utilise lactose (d) they cannot transport lactose from the medium into the cell.

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

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 operator region. (iii)The z-gene codes for permease. (iv) This was elucidated by Francois Jacob and Jacques Monod. The correct statements are (a) (ii) and (iii) (b) (i) and (iii) (c) (ii) and (iv) (d) (i) and (ii)

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)

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 because excess of β-galactosidase can switch off transcription (c) positive and inducible because it can be induced by lactose (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.

Which of the following is required as inducer(s) for the expression of Lac operon? (a) Lactose (b) Lactose and galactose (c) Glucose (d) Galactose

Description : Which of the following is required as inducer(s) for the expression of Lac operon? (a) Lactose (b) Lactose and galactose (c) Glucose (d) Galactose

Last Answer : Lactose

Select the incorrect statement out of the five given below about lac operon when Lactose is present in the medium. a) Gene – A gets transcribed into mRNA which produces β-galactoside permease b) Inducer-Repressor complex is formed c) Lactose inactivates repressor protein d) RNA polymerase transcribe Z-gene, Y-gene and A-gene e) Allolactose is the inducer of lac operon

Description : Select the incorrect statement out of the five given below about lac operon when Lactose is present in the medium. a) Gene - A gets transcribed into mRNA which produces β-galactoside permease b) ... polymerase transcribe Z-gene, Y-gene and A-gene e) Allolactose is the inducer of lac operon

Last Answer : Gene – A gets transcribed into mRNA which produces β-galactoside permease b) Inducer-Repressor complex is formed

5. Lac operon transcribed when a) lactose is needed by the cell b) lactose is available to the cell c) lactic acid is needed by the cell d) lactic acid is available to the cell

Description : 5. Lac operon transcribed when a) lactose is needed by the cell b) lactose is available to the cell c) lactic acid is needed by the cell d) lactic acid is available to the cell

Last Answer : b) lactose is available to the cell

Enzyme lactase is responsible for the breakdown of lactose into

Description : Enzyme lactase is responsible for the breakdown of lactose into

Last Answer : Enzyme lactase is responsible for the breakdown of lactose into A. Glucose + Fructose B. Glucose + ... . Glucose + Glucose D. Fatty acids + Glycerol

Why is the lac operon said to be an inducible operon? -Biology

Description : Why is the lac operon said to be an inducible operon? -Biology

Last Answer : answer:

What does the lac operon in bacteria code for? -Biology

Description : What does the lac operon in bacteria code for? -Biology

Last Answer : answer:

What genes are parts of the lac operon? -Biology

Description : What genes are parts of the lac operon? -Biology

Last Answer : answer:

In Lac-operon, repressor protein binds to

Description : In Lac-operon, repressor protein binds to

Last Answer : In Lac-operon, repressor protein binds to A. Regulator gene B. Operator gene C. Promoter gene D. Structural gene

In the ’lac operon’ concept, which of the following is a protein? (A) Operator (B) Repressor (C) Inducer (D) Vector

Description : In the ’lac operon’ concept, which of the following is a protein? (A) Operator (B) Repressor (C) Inducer (D) Vector

Last Answer : Answer : B

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

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

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

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

Lac operon of E. coli contains _______ is continuity. (A) Regulator and operator genes only (B) Operator and structural genes only (C) Regular and structural genes only (D) Regulator, operator and structural genes

Description : Lac operon of E. coli contains _______ is continuity. (A) Regulator and operator genes only (B) Operator and structural genes only (C) Regular and structural genes only (D) Regulator, operator and structural genes

Last Answer : Answer : D

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

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

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

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

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

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

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

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

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

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

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

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

Lac operon is a cluster of genes present in (A) Human beings (B) E. coli (C) Lambda phage (D) All of these

Description : Lac operon is a cluster of genes present in (A) Human beings (B) E. coli (C) Lambda phage (D) All of these

Last Answer : Answer : B

In the lac operon concept, a protein molecule is (A) Operator (B) Inducer (C) Promoter (D) Repressor

Description : In the lac operon concept, a protein molecule is (A) Operator (B) Inducer (C) Promoter (D) Repressor

Last Answer : Answer : D

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

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

Last Answer : Answer : A

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

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

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) (D) (a) (iii) (iv) (i) (ii) (b) (i) (iii) (ii) (iv) (c) (iii) (i) (ii) (iv) (d) (iii) (i) (iv) (ii)

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)

The lac operon is an example of (a) repressible operon (b) overlapping genes (c) arabinose operon (d) inducible operon.

Description : The lac operon is an example of (a) repressible operon (b) overlapping genes (c) arabinose operon (d) inducible operon.

Last Answer : (d) inducible operon.

.In negative operon, (a) co-repressor binds with repressor (b) co-repressor does not bind with repressor (c) co-repressor binds with inducer (d) cAMP have negative effect on lac operon. (

Description : .In negative operon, (a) co-repressor binds with repressor (b) co-repressor does not bind with repressor (c) co-repressor binds with inducer (d) cAMP have negative effect on lac operon. (

Last Answer : co-repressor binds with repressor

.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.

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

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

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

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) (D) (a) (iii) (iv) (i) (ii) (b) (i) (iii) (ii) (iv) (c) (iii) (i) (ii) (iv) (d) (iii) (i) (iv) (ii)

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)

An example of an inducible group of genes is the ______. a. ARG operon b. NAC operon c. LAC operon d. SAC operon

Description : An example of an inducible group of genes is the ______. a. ARG operon b. NAC operon c. LAC operon d. SAC operon

Last Answer : c. LAC operon

The structural genes of lac operon transcribe mRNA which is a) polycistronic b) replicative c) monokaryotic d) monocistronic

Description : The structural genes of lac operon transcribe mRNA which is a) polycistronic b) replicative c) monokaryotic d) monocistronic

Last Answer : a) polycistronic

In E coli Lac operon gets switched on when:

Description : 5. In E coli Lac operon gets switched on when: a) Lactose is present and binds to the repressor b) Repressor binds to the operator c) RNA polymerase binds to the operator d) Lactose is present and binds to the RNA polymerase

Last Answer : a) Lactose is present and binds to the repressor

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

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

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

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

Which enzyme will be produced in a cell if there is a nonsense mutation in the lac Y gene? (a) Transacetylase (b) Lactose permease and transacetylase (c) β-galactosidase (d) Lactose permease

Description : Which enzyme will be produced in a cell if there is a nonsense mutation in the lac Y gene? (a) Transacetylase (b) Lactose permease and transacetylase (c) β-galactosidase (d) Lactose permease

Last Answer : β-galactosidase

Lac is secreted by (a) trees like rubber (b) certain kinds of birds (c) some animals (d) a certain type of insect which feeds on the saps of trees such as Palas, Ber and Kusum

Description : Lac is secreted by (a) trees like rubber (b) certain kinds of birds (c) some animals (d) a certain type of insect which feeds on the saps of trees such as Palas, Ber and Kusum

Last Answer : Ans: (d)

Lac, which is used as sealing wax is produced by - (1) stem (2) root (3) insect (4) bird

Description : Lac, which is used as sealing wax is produced by - (1) stem (2) root (3) insect (4) bird

Last Answer : (3) insect Explanation: Lac is the scarlet resinous secretion of a number of species of insects. There are several lac insects, some of which secrete highly pigmented wax. The Indian lac insect Laccifer lacca is important commercially.

Lac is produced from - (1) atree (2) an insect (3) an cat (4) amuskrat

Description : Lac is produced from - (1) atree (2) an insect (3) an cat (4) amuskrat

Last Answer : (2) an insect Explanation: Lac is the scarlet resinous secretion of a number of species of insects, namely some of the species of the genera Metatachardia, Laccifer, Tachordiella, ... Tachardina of the superfamily Coccoidea, of which the most commonly cultivated species is Kerria lacca.

Pebrine is a disease of (a) silkworm (b) lac insect (c) honeybee (d) fish.

Description : Pebrine is a disease of (a) silkworm (b) lac insect (c) honeybee (d) fish.

Last Answer : (a) silkworm