Which is evidence that structures for proteins determined by X-ray crystallography represent the structures in solution?

TLS Online TPP Program

#Question id: 21263

#Unit 12. Applied Biology

which one of the following is the first edible transgenic variety to reach market?

TLS Online TPP Program

#Question id: 11808

#Unit 6. System Physiology – Plant

In addition to the free bases, which are the only active forms, active cytokinin levels are decreased through;

a) Addition of sugar molecule to the 3, 7, or 9 nitrogen of the purine ring, called glycosylation-mediated inactivation

b) cis-trans isomerisation of zeatin

c) Irreversible cleavage by cytokinin oxidases.

Which of the following is incorrect?

TLS Online TPP Program

#Question id: 19802

#Unit 12. Applied Biology

The low expression level of cry genes seems to be due to the presence in them of sequences not commonly found in plant coding regions. Such as

(1) Localized A+T-rich regions resembling plant intrans 

(2) 18 potential plant polyadenylation signal sequences 

(3) 13 ATTTA sequences, which destabilize mRNA

(4) Codons that are rarely used in plants

Which of the above statements are correct?                

TLS Online TPP Program

#Question id: 13091

#Unit 13. Methods in Biology

To express a yeast gene in E. coli, your task is to design a strategy to insert the yeast gene into the bacterial plasmid. Below is a map of the area of the yeast genome surrounding the gene in which you are interested.

 

The distance between each tick mark placed on the line above is 100 bases in length

Below are the enzymes you can use, with their specific cut sites shown 5’-XXXXXX-3’ 3’-XXXXXX-5’

 

The plasmid is 5,000 bases long and the two farthest restriction enzyme sites are 200 bases apart. The plasmid has an ampicillin resistance gene somewhere on the plasmid distal from the restriction cut sites.

                              

You do the digestion of the insert and the vector and then ligate the two digestions together. You then transform the ligation into bacteria and select for ampicillin resistance. You get three colonies on your transformation plate. You isolate plasmid from each one and cut each plasmid with the enzyme XbaI. You then run your three digestions on an agarose gel and see the following patterns of bands. Describe what each plasmid actually was that was contained in each of the three colonies.

 

Which colony’s plasmid do you actually want to use for your studies?

TLS Online TPP Program

#Question id: 11434

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of the following structure will exits at pH 5.5 and 10.