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TLS Online TPP Program

#Question id: 23682

Assume that you are trying to insert a gene into a plasmid. Someone gives you a preparation of genomic DNA that has been cut with restriction enzyme X. The gene you wish to insert has sites on both ends for cutting by restriction enzyme Y. You have a plasmid with a single site for Y, but not for X. Your strategy should be to

#Unit 14. Methods in Biology
  1. insert the fragments cut with X directly into the plasmid without cutting the plasmid.
  2. cut the plasmid with restriction enzyme X and insert the fragments cut with Y into the plasmid.
  3. cut the DNA again with restriction enzyme Y and insert these fragments into the plasmid cut with the same enzyme.
  4. cut the plasmid twice with restriction enzyme Y and ligate the two fragments onto the ends of the DNA fragments cut with restriction enzyme X.
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TLS Online TPP Program

#Question id: 4561

#Unit 3. Fundamental Processes

Which factor recruits capping enzyme?
TLS Online TPP Program

#Question id: 4659

#Unit 3. Fundamental Processes

Many bacterial responses are controlled by two component regulatory systems. What will happen at the high concentration of glutamine and at the low concentration of glutamine?

a) At high concentrations glutamine binds to a sensor domain of NtrB conformational change in the protein that inhibits its histidine kinase activity

b) NtrC phosphorylation takes place causes a conformational change in NtrC that unmasks the NtrC DNA-binding domain so that it can bind to the glnA enhancers

c) At the same time, the regulatory domain of NtrC blocks its DNA-binding domain from binding the glnA enhancers

d) At low concentrations of glutamine dissociates from the sensor domain in the NtrB protein, leading to activation of a histidine kinase transmitter domain

Which of the following given combination is correct?
TLS Online TPP Program

#Question id: 4660

#Unit 3. Fundamental Processes

Two-component system regulating response to low Gln,

a) Glutamine dissociates from the sensor domain in the NtrB protein, leading to activation of a histidine kinase transmitter domain in NtrB

b) glutamine binds to a sensor domain of NtrB, causing a conformational change in the protein that inhibits its histidine kinase activity, the regulatory domain of NtrC blocks its DNA-binding domain from binding the glnA enhancers.

c) Activated transmitter domain of NtrB that transfers the γ-phosphate of ATP to a histidine residue (H), this phosphohistidine then transfers the phosphate to an aspartic acid residue (D) in the NtrC protein

d) This causes a conformational change in NtrC that unmasks the NtrC DNA-binding domain so that it can bind to the glnA enhancers

Which of the following combination is correct?
TLS Online TPP Program

#Question id: 4661

#Unit 3. Fundamental Processes

In bacteria two components regulatory systems contain a domain can have function such as controlling the direction in which the bacterium swims in response to a concentration gradient of nutrients is known as
TLS Online TPP Program

#Question id: 4662

#Unit 3. Fundamental Processes

Transcriptional activation by Pol II initiates transcription, polymerase pauses after transcribing fewer than 100 nucleotides due to the action of the elongation inhibitor such as
TLS Online TPP Program

#Question id: 4663

#Unit 3. Fundamental Processes

Which two polymerases function in transcriptional repression directed by nuclear siRNAs in plants?