You are studying a new strain of E. coli that can utilize the disaccharide melibiose very efficiently. You find that utilization depends on the enzyme melibiase, which is encoded by the gene Mel1. Mel1 is not expressed unless melibiose is present in the growth medium. You have isolated a mutation that causes constitutive melibiase activity, which you designate MelA–. P1 phage mapping experiments using a Tn5 insertion linked to Mel1 show that MelA– is not linked to Mel1. Moreover you find that when an amber suppressor is introduced into a MelA– mutant, normal melibiase regulation is restored. Classify the MelA– mutation on the basis of genetic properties,  make a proposal for the type of regulatory functions affected by the MelA– mutation?

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#Question id: 10388

#SCPH06 I Botany

Phytochrome can interconvert between Pr and Pfr forms, Pr receives red light and converts into Pfr while Pfr receives far-red light and then converts into Pr, so which form of phytochrome is responsible for seed germinations?

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#Question id: 14148

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

Dynamic programming determines optimal alignment by matching two sequences for all possible pairs of characters between the two sequences.

Reason(R): Use of the dynamic programming method requires a scoring system to account for matches and mismatches between sequences, and a scheme for Gap penalties.

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#Question id: 15649

#SCPH05 I Biotechnology

A bacterial culture having a specific oxygen uptake rate of 5 mmol O2 (g DCW)⁻¹ h⁻¹ is being grown aerobically in a fed-batch reactor. The maximum value of the volumetric oxygen transfer coefficient is 0.18 s⁻¹ for the stirred tank bioreactor and the critical dissolved oxygen concentration is 20% of the saturation concentration (8 mg L⁻¹). The maximum density to which the cells can be grown in the fed-batch process, without the growth being limited by oxygen transfer, is approximately

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#Question id: 10521

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

Which is an example of a plant-derived DAMP found in tomato that is produced in response to wounding associated with herbivore activity?

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#Question id: 3915

#SCPH28 | Zoology

Which of the following is true for the unwinding of the DNA helix and the synthesis of a short stretch of RNA?