6351. The air riser is located on the outside of the draft tube for the large-scale airlift bioreactors because of
6352. At the end of the lag phase, when growth begins, the division rate increases gradually and reaches a maximum value in the exponential growth period. This transitional period is commonly called the accelerated growth phase and is often included as a part of the
6353. Which of the following(s) is/are considered the limitations of the exponential growth model?
6354. To describe components of an airlift bioreactor which of the follow-ings are generally included?
6355. The function of the disengagement zone in an airlift fermenter is to
6356. Stationary phase is described as
6357. In the accelerated phase, cell starts to
6358. The monod model predicts that the specific growth rate
6359. A mixed fermentation is one, which produces
6360. She is very beautiful, ...............
6361. The function of the DOS command and DIR/OD/S is :
6362. GUI stands for :
6363. One who can use both hands equally well
6364. If I..............more free time, I would learn Italian.
6365. Mixing in an anaerobic sludge blanket reactor is due to
6366. In batch culture, protogon is produced from peptone during the stationary phase with a yield of 0.4 protogon mg per g of peptone. If it is to be produced in a chemostat at a dilution rate of 0.5 h-1 from a medium containing 10 g.l-1 of peptone, then the rate of protogon synthesis would be
6367. Formation of end product by Lactococcus lactis will become non-growth associated as lactic acid accumulates because
6368. Which of the following would not be subjected to the "glucose effect"?
6369. Immobilized cell reactors for wastewater treatment have the advantage of having/being
6370. Which of the statement is true for continuous reactor at steady state?
6371. A continuous bioreactor in which only the flow rate is used to control the rate of cell or product productivity is called
6372. For organisms growing in a chemostat, the specific growth rate
6373. Saccharomyces cerevisiae is being grown in a chemostat converts glucose to biomass, ethanol, glycerol and carbon dioxide. At steady state, the concentration of glucose, biomass, ethanol and glycerol will
6374. In aerobic yeast fermentation for production of citric acid from alkanes using a fed-batch culture, why alkanes are slowly fed to the yeast?
6375. A continuous reactor has a dilution rate of 0.5 h-1. Its residence time would be
6376. Which of the following is used to calculate mass of substrate in the reactor?
6377. If biomass yields are constant, then the biomass productivity of a culture grown in continuous reactor will
6378. Low dissolved oxygen concentrations leads to
6379. In a continuous reactor, the medium contains 40 g.l-1 of maltose and the medium flow rate is 10 litres per hour and the effluent contains 20 g.l-l of lactate. What is the productivity of lactate production from this reactor?
6380. A fed-batch reactor containing 1 g.l-1 of substrate in 2 litre of medium. It is fed with 1 g.l-l of substrate at the rate of 1 litre per hour. After 10 hours, the concentration of substrate in the reactor was 0.5 g.l-1 . The mass of substrate that was used by the culture in the reactor was
6381. Toxins accumulated in a reactor can lead to low biomass yields probably due to which of the following?
6382. The cellular productivity in a continuous stirred tank fermenter (CSTF) increases with an increase in the dilution rate and reaches a maximum value. If the dilution rate is increased beyond the maximum point, the productivity will
6383. Fluidized bed bioreactors provide higher mass transfer rates than packed bed bioreactors because
6384. In fed-batch fermentation, mass of substrate utilized is calculated using the relationship
6385. A chemostat has a liquid volume of 2 litres and is being fed at a rate of 4 litres per hour. Dilution rate for this reactor will be
6386. Mixing per unit volume is observed to be poorest in
6387. The growth of an organism on glucose is described by the following Monod model parameters: μm = 0.5 h-1 and Ks =0.1 g.l-1, if the concentration of glucose in the feed is 10 g.l-1 and the dilution rate is set to 0.4 h-1, then the steady state concentration of glucose in the effluent will be
6388. A continuous reactor at steady state contains 0.04 g.l-1 of biomass and 0.02 g.l-1 of phenol. The feed contained 0.1 g.l-1 of phenol. The biomass yield would be
6389. A culture system with constant environmental conditions maintained through continual provision of nutrient and removal of wastes is called __________ culture system.
6390. The main reason for production of antibiotics in fed batch reactors is
6391. Fed batch reactors is used to produce vinegar because
6392. When a culture of fermenting yeast becomes metabolically uncoupled, ethanol
6393. Mixing profiles closest to plug flow are observed in
6394. On a glucose medium, the growth of an organism is characterized by the following Monod model and stoichiometric parameters μm = 0.3 h-1, Ks =0.05 g.l-1 and Yxs = 0.3 g.g-1 When this organism is grown in a 2 litre continuous on a medium containing 10 g.l-1 of glucose added at 1 l.h-1, the steady state concentration of biomass in the reactor will be
6395. Unsteady state mass balance for dynamic model of continuous stirred tank reactor (CSTR) is
6396. A fed-batch reactor initially contains 2 litre of medium. If it was fed at 1 litre per hour, then after 10 hours, the volume of the reactor will be
6397. A Bacillus sp. produces an antibiotic only during the stationary phase when grown in a batch culture. If grown in a 5 litre continuous culture, the steady state productivity of the antibiotic
6398. In a fluidized bed reactor, the function of the disengagement zone is to
6399. Saccharomyces cerevisiae produces high biomass yields at low glucose concentrations and high dissolved oxygen concentrations. Which of the following should be followed for maximizing its biomass productivity?
6400. In a glucose-yeast extract medium, Lactococcus lactis has a maximum specific growth rate (um) of 1.23 h-1. What would be the specific growth rate of this organism at steady state in a 4 litre reactor being fed at 2 litres per hour?