C. roseus cells immobilized in Ca-alginate beads of diameter 0.5 mm are used for production of indole alkaloids (IA) in a fluidized-bed bioreactor. The rate limiting nutrient is glucose and no intraparticle diffusion limitations exist. Use the following data: Flow rate of the feed: Q = 1 l/h, Glucose in the feed: So = 30 g/l, Plant Cell Concentration: X = 6 g/l reac. The rate constant for IA formation: k = 5 d-1 (g/l)-1 Ks = 0.4 g/l, Column diameter: Do = 0.15 m. Growth is negligible and Monod kinetics is valid. For 95% glucose conversion determine required hydraulic residence time.

#Question id: 3906

#Section 3: Genetics, Cellular and Molecular Biology

Which subunit of the E. coli core RNA polymerase (a2bbʹw) contributes to DNA binding?

A) a                 B) b                 C) bʹ                D) w

#Question id: 1892

#Section 2: General Biology

The Arthus reaction is characterized by an intense infiltration by:

#Question id: 27256

#Section 3: Genetics, Cellular and Molecular Biology

Which of the following statement is NOT true?

#Question id: 14297

#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. Determine substrate concentrations entering the second reactor.

#Question id: 2093

#Section 2: General Biology

Which of the following is transmembrane proteins?