Gels of 15% polyacrylamide are useful for separating proteins in the range Mr = 100,000 to 10,000,  while a 7.5% gel are used to separate 

#Question id: 14267

#Section 5: Bioprocess Engineering and Process Biotechnology

In a trickling biological filter, the BOD value of the feed stream is S_0i = 500 mg/l with a feed flow of F = 10³ l/h. The effluent BOD value is desired to be S₀ = 10 mg/l. The following kinetic parameters for the biocatalysts are known: r_m = 20 mg/S/l .h and K_s = 200 mg S/l. The biofilm thickness is L = 0.1 mm. The cross-sectional area of the filter is A = 2 m² , and the biofilm surface area per unit volume of the bed is a = 500 cm² /cm³ . Assume that dissolved oxygen is the rate-limiting substrate and the diffusion coefficient of oxygen is D_O2 = 2 × 10^-5 cm² /s. Determine the required height of the bed. You can assume first-order bioreaction kinetics?

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#Question id: 14480

#Section 1: Engineering Mathematics

#Question id: 1873

#Section 2: General Biology

Mutations in the gene encoding which of the following most commonly results in severe combined immunodeficiency (SCID)?

#Question id: 3353

#Section 3: Genetics, Cellular and Molecular Biology

#Question id: 1121

#Section 3: Genetics, Cellular and Molecular Biology

Which of the following provides the best evidence that cell-signaling pathways evolved early in the history of life?