⚗️ Biochemical Engineering Solved MCQs with Answers

Practice 513 approved ⚗️ Biochemical Engineering questions with verified answers from the 🧬 Medical Science subject for Pakistan exams.

513 solved MCQs

The SI unit for viscosity isAnswer: kg.m⁻¹.s⁻¹ The viscous nature of a non-Newtonian fluidAnswer: Changes with the level of power input and/or the length of time during which the fluid is mixed Which of the following compound, if added to a solution will lead to the greatest increase in viscosity?Answer: A long chain protein such as albumin A Brookfield viscometer measures viscosity by determiningAnswer: The torque required to move an impeller at a set speed Which of the following factors will affect the sensitivity of animal cells to shear conditions?Answer: All of these The best described action of Pluronic F68 (non-ionic detergent) in a cell culture medium is that, itAnswer: Acts on the surface properties of the cells and the culture medium Water is aAnswer: Newtonian fluid Which of the following affect the Kolmogorov eddy size?Answer: All of these A liquid is flowing at 11,400 l.h⁻¹ along a pipeline having a diameter of 4 cm. If the liquid has a density of 1 g.ml⁻¹ and viscosity of 0.001kg.m⁻¹.s⁻¹, then the liquid would be in theAnswer: Turbulent phase The viscosity of a fluid increases with the length of time that it is being mixed. This fluid would be best described as beingAnswer: Rheopectic Which of the following can act as a shear protectorant?Answer: Serum The viscosity of a fluid increases with increasing stirrer speed. This fluid would be best described as beingAnswer: Dilatant A dilatant fluid is one in which the viscosityAnswer: Increases with increasing stirrer speed A rheopectic fluid is one in which the viscosityAnswer: Increases with mixing time A fluid in which the viscosity increases with increasing stirrer speed and mixing time can be called asAnswer: Dilatant, rheopectic fluid The medium will have the highest viscosity (considering that the cells do not secrete gums) with the presence ofAnswer: Filamentous fungi that grow as long poorly branched chains A Newtonian fluid is one in which the viscosityAnswer: Is constant regardless of the stirrer speed or mixing time Which pattern of mixing is preferred in stirred tank reactors during the culture of aerobic microorganisms?Answer: Turbulent flow Animal cell cultures do not have much effect on shear forces becauseAnswer: The cell size is generally smaller than the critical eddy size at which shear will have an effect The viscosity of the culture fluid is classified as both pseudoplastic and thixotropic which indicates that the viscosityAnswer: Decreases with stirring speed and decreases with mixing time Pluronic F68 is added to cell culture media asAnswer: A shear protectorant A stirred tank reactor containing a fluid with a density of 2.5 g.ml⁻¹ and viscosity of 0.002 kg m⁻¹s⁻¹ is mixed at 120 rpm. If the fluid is mixed with an impeller having diameter 50 cm, then the Reynolds number of the liquid in the reactor isAnswer: 12,50,000 If the viscosity of a fluid decreases with the length of time that it is being mixed, then this fluid isAnswer: Thixotropic Which of the following describes the importance of the Kolmogorov eddy size in the biotechnology?Answer: All of these A thixotropic fluid is one in which the viscosityAnswer: Decreases with mixing time Newtonian fluid is one in which the viscosityAnswer: Remains constant with time and power input Reynolds number for laminar flow over a plate should be less thanAnswer: 5 x 10⁵ The approach which is commonly used to determine the level of damage to animal cells in a culture medium is to monitorAnswer: The level of lactate dehydrogenase activity A Brookfield viscometer cannot determine the shear stress becauseAnswer: The shear stress is not defined Which of the following is correct?Answer: The viscosity of gases increases with increasing temperature, but decreases in liquids