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TLS Online TPP Program

#Question id: 3572

How might the ability of pea plants to self fertilize be a problem for genetic experiments?

#Section 3: Genetics, Cellular and Molecular Biology

  1. Self fertile plants tend to be weaker and require more care.

  2. Self fertile plants are not able to produce viable seeds due to inbreeding.

  3. Stamens must be removed from self fertile plants to control fertilization.

  4. Pistils of self fertile plants are unable to accept pollen from other plants.

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TLS Online TPP Program

#Question id: 14298

#Section 5: Bioprocess Engineering and Process Biotechnology

A two-stage chemostat system is used for production of secondary metabolite. The volume of each reactor is 0.5 m3; the flow rate of feed is 50 l h- 1. Mycelial growth occurs in the first reactor; the second reactor is used for product synthesis. The concentration of substrate in the feed is 10 gl-1. Kinetic and yield parameters for the organism are:

                                                            

Assume that product synthesis is negligible in the first reactor and growth is negligible in the second reactor. What is the overall substrate conversion?

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TLS Online TPP Program

#Question id: 14299

#Section 5: Bioprocess Engineering and Process Biotechnology

A two-stage chemostat system is used for production of secondary metabolite. The volume of each reactor is 0.5 m3; the flow rate of feed is 50 l h- 1. Mycelial growth occurs in the first reactor; the second reactor is used for product synthesis. The concentration of substrate in the feed is 10 gl-1. Kinetic and yield parameters for the organism are:

                                                        

Assume that product synthesis is negligible in the first reactor and growth is negligible in the second reactor. What is the final concentration of product?

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TLS Online TPP Program

#Question id: 14300

#Section 5: Bioprocess Engineering and Process Biotechnology

A 15-m 3 chemostat is operated with dilution rate 0.1 h-1. A continuous steriliser with steam injection and flash cooling delivers sterilized medium to the fermenter. Medium in the holding section of the steriliser is maintained at 130⁰C The concentration of contaminants in the raw medium is 105 ml-l; an acceptable contamination risk is one organism every 3 months. The Arrhenius constant and activation energy for thermal death are estimated to be 7.5 × 1039 h-1 and 288.5 kJ gmol- 1, respectively. The steriliser pipe inner diameter is 12 cm. At 130⁰C the liquid density is 1000 kg m- 3 and the viscosity is 4 kg m- 1 h- 1. Assuming perfect plug flow, determine the length of the holding section.   __________________
TLS Online TPP Program

#Question id: 14301

#Section 5: Bioprocess Engineering and Process Biotechnology

Pseudomonas sp. has a mass doubling time of 2.4 h when grown on acetate. The saturation constant using this substrate is 1.3 g/l (which is unusually high), and cell yield on acetate is 0.46 g cell/g acetate. If we operate a chemostat on a feed stream containing 38 g/l acetate, find the Cell concentration when the dilution rate is one-half of the maximum?

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TLS Online TPP Program

#Question id: 14302

#Section 5: Bioprocess Engineering and Process Biotechnology

Pseudomonas sp. has a mass doubling time of 2.4 h when grown on acetate. The saturation constant using this substrate is 1.3 g/l (which is unusually high), and cell yield on acetate is 0.46 g cell/g acetate. If we operate a chemostat on a feed stream containing 38 g/l acetate, find the Substrate concentration when the dilution rate is 0.8Dmax?

                        __________________                                      
TLS Online TPP Program

#Question id: 14303

#Section 5: Bioprocess Engineering and Process Biotechnology

Pseudomonas sp. has a mass doubling time of 2.4 h when grown on acetate. The saturation constant using this substrate is 1.3 g/l (which is unusually high), and cell yield on acetate is 0.46 g cell/g acetate. If we operate a chemostat on a feed stream containing 38 g/l acetate, find the Maximum dilution rate?

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