In the Meselson-Stahl DNA replication experiment, if the cells were first grown for many generations in 15N containing media, and then switched to 14N containing media, what percent of the DNA had 1 light strand and 1 heavy strand after 2 generations of growth in 15N growth media?

#Question id: 4168

#Section 3: Genetics, Cellular and Molecular Biology

The deaminoacylated tRNA leaves the ribosome as the growing polypeptide passes through the tunnel of the large ribosomal subunit from the __.

#Question id: 15726

#Section 6: Plant, Animal and Microbial Biotechnology

#Question id: 27216

#Section 5: Bioprocess Engineering and Process Biotechnology

Mechanical agitation is not required in the following:

#Question id: 14175

#Section 5: Bioprocess Engineering and Process Biotechnology

The growth of S. cerevisiae on glucose under anaerobic conditions can be described by the following overall reaction

Determine the biomass yield coefficient YX/S? 

#Question id: 14200

#Section 5: Bioprocess Engineering and Process Biotechnology

A fluidized-bed, immobilized-cell bioreactor is used for the conversion of glucose to ethanol by Z. mobilis cells immobilized in k-carrageenan gel beads. The dimensions of the bed are 10 cm (diameter) by 200 cm. Since the reactor is fed from the bottom of the column and because of CO₂ gas evolution, substrate and cell concentrations decrease with the height of the column. The average cell concentration at the bottom of the column is X₀ = 45 g/l, and the average cell concentration decreases with the column height according to the following equation:

where Z is the column height (cm). The specific rate of substrate consumption is q_S = 2 g S/g cells . h. The feed flow rate and glucose concentration in the feed are 5 l/h and 160 g glucose/l, respectively.

Determine the ethanol concentration in the effluent (g/l . h) if YP/S = 0.48 g ethanol/g glucose