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TLS Online TPP Program

#Question id: 15416

Which of the following statements are regarding to lens induction in xenopus is incorrect?

#Part-B Specialized Branches in Biotechnology
  1. Lens induction can be achieved in the presence of optic vesicle after priming of head ectoderm by the anterior neural plate.
  2. The optic vesicle can induce the presumptive head ectoderm to form the lens.
  3. Under the influence of factors secreted by the lens, the optic vesicle becomes retina.
  4. The anterior neural plate primes the head ectoderm via BMP4 and Fgf8 prior to signals from the optic vesicle.
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TLS Online TPP Program

#Question id: 14218

#Part-A Aptitude & General Biotechnology

In CSTR system at steady rate  
TLS Online TPP Program

#Question id: 14221

#Part-B Specialized Branches in Biotechnology

E. coli have a maximum respiration rate, qO2max, of about 240-mg O2/g-dry wt-h. It is desired to achieve a cell mass of 20 g dry wt/l. The kLa is 120 h-1 in a 1000-l reactor (800 l working volume). A gas stream enriched in oxygen is used (i.e., 80% O2) which gives a value of C* = 28 mg/L. If oxygen becomes limiting, growth and respiration slow; for example,

                                     
   where CL is the dissolved oxygen concentration in the fermenter. What is CL when the cell mass is  at 20 g/l?
TLS Online TPP Program

#Question id: 14237

#Part-B Specialized Branches in Biotechnology

A genetically-engineered strain of yeast is cultured in a bioreactor at 30⁰C for production of heterologous protein. The oxygen requirement is 80 mmol 1-1 h-I; the critical oxygen concentration is 0.004 mM. The solubility of oxygen in the fermentation broth is estimated to be 10% lower than in water due to solute effects. What is the minimum mass-transfer coefficient necessary to sustain this culture if the reactor is sparged with air at approximately 1 atm pressure ?         
TLS Online TPP Program

#Question id: 14238

#Part-B Specialized Branches in Biotechnology

A genetically-engineered strain of yeast is cultured in a bioreactor at 30⁰C for production of heterologous protein. The oxygen requirement is 80 mmol 1-1 h-I; the critical oxygen concentration is 0.004 mM. The solubility of oxygen in the fermentation broth is estimated to be 10% lower than in water due to solute effects. What mass-transfer coefficient is required if pure oxygen is used instead of air?                       
TLS Online TPP Program

#Question id: 14253

#Part-B Specialized Branches in Biotechnology

Hybridoma cells immobilized on surfaces of Sephadex beads are used in a packed column for production of monoclonoal antibodies (Mab). Hybridoma concentration is approximately X = 5 g/l in the bed. The flow rate of the synthetic medium and glucose concentration are Q = 2 l/h and S0 = 40 g/l, respectively. The rate constant for Mab formation is k = 1 gX/l-d. Assume that there are no diffusion limitations and glucose is the rate limiting nutrient.  Determine the volume of the packed bed for 95% glucose conversion. Bed diameter is D0 = 0.2 m. Neglect the growth of the hybridomas and assume first order kinetics. 
TLS Online TPP Program

#Question id: 14254

#Part-B Specialized Branches in Biotechnology

Hybridoma cells immobilized on surfaces of Sephadex beads are used in a packed column for production of monoclonoal antibodies (Mab). Hybridoma concentration is approximately X = 5 g/l in the bed. The flow rate of the synthetic medium and glucose concentration are Q = 2 l/h and S0 = 40 g/l, respectively. The rate constant for Mab formation is k = 1 gX/l-d. Assume that there are no diffusion limitations and glucose is the rate limiting nutrient.  Determine the height of the packed bed for 95% glucose conversion. Bed diameter is D0 = 0.2 m. Neglect the growth of the hybridomas and assume first order kinetics.