Escherichia coli preferentially utilizes glucose by preventing the uptake of lactose and switching off transcription of the lac operon. This mechanism is known as 

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#Question id: 4165

#SCPH28 | Zoology

Which is true about proofreading activity during the synthesis of aminoacyl-tRNAs?

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#Question id: 17654

#I Life Science/ Life Sciences Group – I-V

The protein concentration in DNA extraction sample measured by

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#Question id: 10928

#I Life Science/ Life Sciences Group – I-V

A 40-year-old woman visits the clinic complaining of fatigue. She had recently been treated for an infection. Her laboratory values are RBC 1.8 × 106/μl, Hb 5.2 g/dL, hematocrit (Hct) 15, WBC 7.6 × 103/μl, platelet count 320,000/μl, mean corpuscular volume (MCV) 92 fL, and reticulocyte count 24%. What is the most likely explanation for this presentation?

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#Question id: 15638

#SCPH01 Biochemistry

You have isolated two mutations that show decreased expression of the Lac operon. However, unlike like the promoter mutations, these mutations don’t respond to the inducer IPTG. These mutations, designated Lac3– and Lac4–, are evaluated for the quantity of ß-galactosidase and permease activity expressed with or without IPTG:

 

Mapping experiments reveal that Lac3– and Lac4– are different short deletions located in the region before the start of the LacZ gene. Given the data shown above suggest which genetic element(s) in addition to part of the promoter has been deleted in each mutant. 

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#Question id: 545

#SCPH28 | Zoology

Which one of the following is not among the six internationally accepted classes of enzymes?