Nutrient medium is to be heated from 10⁰C to 28⁰C is a single-pass countercurrent shell-and-tube heat exchanger before being pumped into a fed-batch fermenter. Medium passes through the tubes of the exchanger; the shell-side fluid is water which enters with flow rate 3 x 10^4 kg h^- 1 and temperature 60⁰C pre-heated medium is required at a rate of 50 m^3 h^-1. The density, viscosity and heat capacity of the medium are the same as water; the thermal conductivity of the medium is 0.54 Wm^- 1 ⁰C ^- 1. It is proposed to use 30 steel tubes with inner diameter 5 cm; the tubes will be arranged in line. The pipe wall is 5-mm thick; the thermal conductivity of the metal is 50 Wm^- 1 ⁰C ^- 1. The maximum linear shell-side fluid velocity is estimated as 0.15 m s^-1. Calculate the log-mean temperature difference _________

#Question id: 535

#Section 4: Fundamentals of Biological Engineering

In some diabetic patients, glucose increases disproportionately and is unresponsive to an insulin challenge; under these conditions, how would oneʹs liver normally respond?

A) phosphorylating glucose for entry into the glycolytic pathway

B) saturating glucokinase with glucose

C) phosphorylating glucose for entry into the glycogen synthesis pathways

#Question id: 538

#Section 4: Fundamentals of Biological Engineering

Which of the following statements are correct about cells that form ATP mainly by glycolysis are

A) anaerobic yeasts.

B) lactic acid bacteria.

C) kidney medulla cells.

#Question id: 540

#Section 4: Fundamentals of Biological Engineering

During strenuous exercise, the NADH formed in the glyceraldehyde 3-phosphate dehydrogenase reaction in skeletal muscle must be reoxidized to NAD+ if glycolysis is to continue.  The most important reaction involved in the reoxidation of NADH is:

#Question id: 541

#Section 4: Fundamentals of Biological Engineering

The overall △G for glycolysis is -72 kJ/mol in erythrocytes. Which statement below is true?

A) The value of △G0ʹ is also -72 kJ/mol since the cytosol pH is close to 7.

B) The free energy of glycolysis is found as the sum of the standard free energy changes for

the individual pathway reactions.

C) The negative sign of △G shows that this pathway will proceed toward product (pyruvate) under normal cellular conditions.

#Question id: 542

#Section 4: Fundamentals of Biological Engineering

Hamsters love to run on exercise wheels. Prolonged running at a high rate of speed requires ATP. Could a hamster with a defective gene for the enzyme lactate dehydrogenase meet the extra ATP demand for prolonged, fast wheel-running by maintaining a high rate of glycolysis? Why or why not?

#Question id: 543

#Section 4: Fundamentals of Biological Engineering

If glucose labeled with 14C at C^-1 (the aldehyde carbon) were metabolized in the liver, the first radioactive pyruvate formed would be labeled in: