Which statement is not right about bacterial genetics materials?
A. RTF in R-plasmid codes sex pili;
B. R-plasmid responsible for drug-resistance;
C. All R plasmids are conjugative plasmid.
D. R-plasmid carries R determinants.
查看答案
A plasmid is:
A. extrachromosomal DNA which closed circular double stranded molecule.
B. a molecule of RNA found in bacterial cells
C. distinguished from a chromosome by being circular
D. a structure in bacterial cells formed from plasma membrane
Which statement about bacterial chromosome is not right?
A. It is a circular, double stranded DNA molecule
B. It is haploid genome.
C. It is supercoiled and tightly packaged in the nucleoid.
D. It is a linear, long DNA molecule in the nucleoid.
Which statement about operon within bacterial chromosome DNA is not right?
A. In an operon, the same promoter can regulate the expression of several genes.
B. One RNA polymerase mediates the transcription of several copies of RNA.
C. An Operon is typically polycistronic.
D. Anoperon consists of a promoter linked witha series of genes.
Bacterial DNA can be transcribed into five types of RNA. Which type of RNAmediates synthesis of a new DNA chain in replication?
A. RNA primer ;
B. rRNA;
C. mRNA;
D. tRNA
微信支付 
支付宝支付