Description : A group of genes whose activity is coordinated by a DNA site is called: (1) operon (2) cistron (3) polysome (4) polypeptide
Last Answer : operon
Description : A group of genes whose activity is coordinated by a DNA site is – (1) operon (2) cistron (3) polysome (4) polypeptide
Last Answer : (1) operon Explanation: The operon is defined as a group of genes whose activity is coordinated by a DNA site. An operon is a functioning unit of genomic DNA containing a cluster ... together in the cytoplasm, or undergo trans-splicing to create monocistronic mR-NAs that are translated separately.
Description : In a eukaryotic microbe, those sections of a primary RNA transcript that will NOT be translated are called a. Introns. b. Anticodons. c. ―Jumping Genes.‖ d. Exons.
Last Answer : a. Introns.
Description : Ribosomes match up the ______ of the mRNA and the ______ of the tRNAs. a. codons; anticodons b. introns; exons c. anticodons; codons d. genes; anticodons
Last Answer : a. codons; anticodons
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
Description : Which one of the following statements is NOT true of the bacterial chromosome? a. It Is Located In The Nucleoid. b. It Usually Isa Single, Circular Molecule. c. Some Genes Are Dominant To Others. d. It Usually Is Haploid.
Last Answer : c. Some Genes Are Dominant To Others.
Description : The function of a repressor protein in an operon system is to prevent synthesis by binding to (A) The ribosome (B) A specific region of the operon preventing transcription of structural genes (C) The RNA polymerase (D) A specific region of the mRNA preventing translation to protein
Last Answer : Answer : B
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 : 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 : Major Histo Compatibility Complex (MHC) is a collection of genes arrayed on A- chromosome 21 in man, chromosome 6 in mice B- chromosome 6 in man, chromosone 21 in mice C- chromosome 17in man, chromosome 6 in mice D- chromosome 6 in man, chromosome 17 in mice
Last Answer : chromosome 6 in man, chromosome 17 in mice
Description : Plasmids a. Replicate with the bacterial chromosome. b. Contain essential growth information. c. May contain antibiotic resistance genes. d. Are as large as the bacterial chromosome.
Last Answer : c. May contain antibiotic resistance genes.
Description : The translation of a mRNA by multiple ribosomes is called formation. a. Okazaki b. Polysome c. Plasmid d. Transposon
Last Answer : b. Polysome
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 : In split genes, the coding sequences are called (a) exons (b) cistrons (c) introns (d) operons
Last Answer : (d) operons.
Description : In split genes, the coding sequences are called (a) exons (b) cistrons (c) introns (d) operons.
Last Answer : (a) exons
Description : The coding sequences found in split genes are called a) Operons b) introns c) exons d) cistrons
Last Answer : c) exons
Description : Bacterial genes lack (a) Exons (b) Introns (c) Prometers (d) Operator
Last Answer : (b) Introns
Description : Which of the following statement describes plasmids? A- Another name for a protoplast B- A complex membrane structure that covers the chromosome of bacteria Small, circular DNA molecules that can exist independently of chromosomes commonly C- found in bacteria D- None of the above
Last Answer : found in bacteria
Description : By some estimates, about ______ of our 25,000 genes are identical to those in some members of the Bacteria. a. 10 b. 20 c. 200 d. 1000
Last Answer : c. 200
Description : The species of bacteria, which possesses 250 genes for lipid biosynthesis is A- M. genitalium B- M. tuberculosis C- E. coli D-H. influenza
Last Answer : M. tuberculosis
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 : 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 : RNA polymerase holoenzyme binds to lac operon at the following site: (A) i gene (B) z gene (C) Operator locus (D) Promoter region
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
Description : Which of the following statements concerning abnormalities of the haemoglobin molecule is true? 1) Alpha thalassaemia is due to a deficiency of beta-chain production 2) HbS is caused by a ... is an adverse prognostic sign 5) oliguneoclitide probes may assist in the diagnosis of haemoglobinopathies
Last Answer : Answers-2 Alpha Thalassaemia is due to abnormalities of the alpha chain. Persistence of HbF has survival advnatages in severely affected subjects. C-alpha 16, beta 11. e-Hb electrophoresis(Dr Shu Ho)
Description : With regard to HLA class 1 antigen: a. they are expressed on all nucleated cells b. they are essential for viral antigen recognition by cytotoxic cells c. the genes for HLA class 1 molecules are located on chromosome 6 and 15 d. all above
Last Answer : all above
Description : The colour blindness is more likely to occur in males than in females because (a) the Y-chromosome of males have the genes for distinguishing colours (b) genes for characters are located on the sex- chromosomes (c) the trait is dominant in males and recessive in females (d) none of these.
Last Answer : (b) genes for characters are located on the sex- chromosomes
Description : The recessive genes located on X-chromosome humans are always (a) lethal (b) sub-lethal (c) expressed in males (d) expressed in females.
Last Answer : (c) expressed in males
Description : Independent assortment of genes does not take place when (a) genes are located on homologous chromosomes (b) genes are linked and located on same chromosome (c) genes are located on non-homogenous chromosome (d) all of these.
Last Answer : genes are linked and located on same chromosome
Description : In a test cross involving F1 dihybrid flies, more parental-type offspring were produced than the recombinant-type offspring. This indicates (a) the two genes are linked and present on the ... two genes are located on two different chromosomes (d) chromosomes failed to separate during meiosis.
Last Answer : (a) the two genes are linked and present on the same chromosome
Description : True statements about the nucleic acid include: a. contains purine and pyrimidine which are bound together by covalent bonds b. there is always an equal concentration of purine and pyrimidine c. in RNA, ... d. introns is more common than exons on the DNA e. the histones mark the excision site
Last Answer : there is always an equal concentration of purine and pyrimidine
Description : The process of conjugation in bacteria requires that _____. a. Two Types Of Viruses Be Present. b. The Conjugating Bacteria Be Deprived Of Nutrients. c. Two Bacteria Exchange Dna. d. Two Live Bacteria Come Together.
Last Answer : d. Two Live Bacteria Come Together.
Description : What genes are parts of the lac operon? -Biology
Last Answer : answer:
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
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
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
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
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
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
Description : Trancription of z, y and a genes of lac operon is prevented by (A) Lactose (B) Allo-lactose (C) Repressor (D) cAMP
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
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
Description : Lac operon is a cluster of genes present in (A) Human beings (B) E. coli (C) Lambda phage (D) All of these
Description : Which one of the following is wrongly matched? (a) Transcription - Writing information from DNA to tRNA. (b) Translation - Using information in mRNA to make protein. (c) Repressor protein - Binds to operator to stop enzyme synthesis. (d) Operon - Structural genes, operator and promoter.
Last Answer : (c) Repressor protein - Binds to operator to stop enzyme synthesis.
Description : .All of the following are part of an operon except (a) an operator (b) structural genes (c) an enhancer (d) a promoter.
Last Answer : d) a promoter.
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 lac operon is an example of (a) repressible operon (b) overlapping genes (c) arabinose operon (d) inducible operon.
Last Answer : (d) inducible operon.