A 200-1itre stirred fermenter contains a batch culture of Bacillus subtilis bacteria at 28⁰C Air at 20⁰C is pumped into the vessel at a rate of 1 vvm; (vvm stands for volume of gas per volume of liquid per minute). The average pressure in the fermenter is 1 atm. The volumetric flow rate of off-gas from the fermenter is measured as 189 l min^-1. The exit gas stream is analysed for oxygen and is found to contain 20.1% 0₂. The dissolved-oxygen concentration in the broth is measured using an oxygen electrode as 52% air saturation. The solubility of oxygen in the fermentation broth at 28⁰C and 1 atm air pressure is 7.8 x 10^-3 kg m^-3. Determine the value of k_La for the system ____________

TLS Online TPP Program

#Question id: 8917

#Section 6: Plant, Animal and Microbial Biotechnology

The Hox genes came to regulate each of the following in what sequence, from earliest to most recent?

1. identity and position of paired appendages in protostome embryos

2. formation of water channels in sponges

3. anterior-posterior orientation of segments in protostome embryos

4. positioning of tentacles in cnidarians

5. anterior-posterior orientation in vertebrate embryos

TLS Online TPP Program

#Question id: 8918

#Section 6: Plant, Animal and Microbial Biotechnology

In individual insects of some species, whole chromosomes that carry larval genes are eliminated from the genomes of somatic cells at the time of metamorphosis. A consequence of this occurrence is that

TLS Online TPP Program

#Question id: 8919

#Section 6: Plant, Animal and Microbial Biotechnology

The last common ancestor of all animals was probably a

TLS Online TPP Program

#Question id: 8921

#Section 6: Plant, Animal and Microbial Biotechnology

Evidence of which structure or characteristic would be most surprising to find among fossils of the Ediacaran fauna?

TLS Online TPP Program

#Question id: 8922

#Section 6: Plant, Animal and Microbial Biotechnology

Which statement is most consistent with the hypothesis that the Cambrian explosion was caused by the rise of predator-prey relationships?

TLS Online TPP Program

#Question id: 8923

#Section 6: Plant, Animal and Microbial Biotechnology

Which of these genetic processes may be most helpful in accounting for the Cambrian explosion?