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TLS Online TPP Program

#Question id: 4165

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

#SCPH05 I Biotechnology

  1. Proofreading is accomplished as an amino acid enters the active site of the enzyme. Incorrect amino acids are rejected before any reaction occurs.

  2. Proofreading occurs just after aminoacyl-adenylate formation.

  3. A separate cytosolic proofreading enzyme catalyzes the hydrolysis of incorrect aminoacyl-tRNAs.

  4. No proofreading activity is necessary due to the high level of specificity of all aminoacyl-tRNA synthetases.

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TLS Online TPP Program

#Question id: 14859

#SCPH05 I Biotechnology

Liquid from a brewery fermenter can be considered to contain 10% ethanol and 90% water. 50000 kg h-1 of this fermentation product are pumped to a distillation column on the factory site. Under current operating conditions a distillate of 45% ethanol and 55% water is produced from the top of the column at a rate one-tenth that of the feed.
 What is the composition of the waste 'bottoms' from the still?
TLS Online TPP Program

#Question id: 14860

#SCPH05 I Biotechnology

A fermentation slurry containing Streptomyces kanamyceticus cells is filtered using a continuous rotary vacuum filter. 120 kg h- 1 slurry is fed to the filter; 1 kg slurry contains 60 g cell solids. To improve filtration rates, particles of diatomaceous-earth filter aid are added at a rate of 10 kg h- 1. The concentration of kanamycin in the slurry is 0.05% by weight. Liquid filtrate is collected at a rate of 112 kg h-1; the concentration of kanamycin in the filtrate is 0.045% (w/w). Filter cake containing cells and filter aid is continuously removed from the filter cloth.
 What percentage liquid is the filter cake?
TLS Online TPP Program

#Question id: 14861

#SCPH05 I Biotechnology

A fermentation slurry containing Streptomyces kanamyceticus cells is filtered using a continuous rotary vacuum filter. 120 kg h- 1 slurry is fed to the filter; 1 kg slurry contains 60 g cell solids. To improve filtration rates, particles of diatomaceous-earth filter aid are added at a rate of 10 kg h- 1. The concentration of kanamycin in the slurry is 0.05% by weight. Liquid filtrate is collected at a rate of 112 kg h-1; the concentration of kanamycin in the filtrate is 0.045% (w/w). Filter cake containing cells and filter aid is continuously removed from the filter cloth.
If the concentration of kanamycin in the filter-cake liquid is the same as in the filtrate, how much kanamycin is absorbed per kg filter aid?.,..... 10-4
TLS Online TPP Program

#Question id: 14891

#SCPH05 I Biotechnology

What do you mean by idiophone? 
TLS Online TPP Program

#Question id: 14892

#SCPH05 I Biotechnology

Tyndallisation is method of 
TLS Online TPP Program

#Question id: 14893

#SCPH05 I Biotechnology

An open system in which the growth rate is maintained by the removal and addition of media at such a rate as to maintain a constant cell density is called a