Most genes in prokaryotes are in the form of operons. So why don't eukaryotes have operons?()
A. Eukaryotes regulate gene expression by repressor protein
B. The mRNA of prokaryote is read from 5 'to 3', whereas,in eukaryote,mRNA is read from 3 'to 5'
C. There is only one binding site between ribosome and mRNA in eukaryotes
D. Eukaryotes can't transcribe and translate at the same time
Eukaryotic promoter can not bind to RNA polymerase
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Which of the following is true about lactose operon?()
A. Induced by glucose, inhibited by lactose
B. Induced by lactose and inhibited by cAMP
C. Regulated positively by cAMP and negatively by glucose
D. Regulated positively by lactose and negatively by glucose
E. Induced by lactose and cAMP at the same time
In what combination is lactose turned on?()
A. operatorgene
B. Repressor protein
C. Promoter
D. mRNA
To clone the green fluorescent protein gene downstream of the promoter of proP,what is the purpose of this?()
A. It causes the mutation of proP gene
B. Inducing the transcription of proP gene
Construction of gene library containing green fluorescent protein
D. Green fluorescent protein as a reporter gene to report the promoter activity of proP gene
E. The first step of cloning proP gene into other host cells
What is the function of aminoacyl tRNA synthetase?()
A. Perform transpeptidyl reaction
B. Help tRNA find the A site of ribosome
C. Binding to ribosome binding site sequence of tRNA
D. Transcription of tRNA gene
E. Attaching amino acids to specific tRNA
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