Q.1 Which type of sensor is most commonly used to monitor pH in a bioreactor during therapeutic protein production?
Thermocouple
Amperometric pH electrode
Infrared spectrometer
Capacitive humidity sensor
Explanation - Amperometric pH electrodes generate a voltage proportional to hydrogen ion activity, making them the standard for real‑time pH monitoring in bioprocesses.
Correct answer is: Amperometric pH electrode
Q.2 In a fed‑batch fermentation, what is the primary purpose of the feed pump control algorithm?
Maintain constant temperature
Regulate dissolved oxygen levels
Provide substrate at a controlled rate
Adjust pH automatically
Explanation - Fed‑batch processes add nutrients gradually; the pump algorithm ensures the feed rate matches the growth phase to avoid substrate inhibition.
Correct answer is: Provide substrate at a controlled rate
Q.3 Which control strategy is most suitable for maintaining dissolved oxygen (DO) at a set point in a large‑scale bioreactor?
On‑off control
Proportional‑Integral‑Derivative (PID) control
Bang‑bang control
Open‑loop control
Explanation - PID controllers continuously adjust air/oxygen flow based on the error, the integral of past errors, and the rate of change, providing stable DO regulation.
Correct answer is: Proportional‑Integral‑Derivative (PID) control
Q.4 What is the main advantage of using a single‑use bioreactor (SUB) for therapeutic peptide production?
Higher pressure tolerance
Reduced cleaning validation time
Improved temperature control
Greater mechanical strength
Explanation - SUBs are disposable, eliminating the need for extensive cleaning and sterilization, thus shortening turnaround between batches.
Correct answer is: Reduced cleaning validation time
Q.5 Which electrical component converts the analog signal from a temperature sensor into a digital signal for a PLC?
Relay
Analog‑to‑Digital Converter (ADC)
Transformer
Rectifier
Explanation - An ADC samples the continuous voltage from the sensor and outputs a digital representation that the PLC can process.
Correct answer is: Analog‑to‑Digital Converter (ADC)
Q.6 In chromatography, what does the term "resolution" refer to?
The speed of the mobile phase
The ability to separate two adjacent peaks
The temperature of the column
The pH of the buffer
Explanation - Resolution quantifies how well two compounds are separated; higher resolution indicates clearer distinction between peaks.
Correct answer is: The ability to separate two adjacent peaks
Q.7 Which type of chromatography is most frequently employed for purification of monoclonal antibodies?
Ion‑exchange chromatography
Size‑exclusion chromatography
Affinity chromatography
Gas chromatography
Explanation - Protein A affinity chromatography specifically binds the Fc region of antibodies, providing high selectivity and yield.
Correct answer is: Affinity chromatography
Q.8 A SCADA system in a bioprocess plant primarily provides:
Mechanical stirring of bioreactors
Real‑time data acquisition and visualization
Chemical synthesis of peptides
Manual valve operation
Explanation - SCADA (Supervisory Control and Data Acquisition) gathers sensor data, displays it, and allows operators to control processes remotely.
Correct answer is: Real‑time data acquisition and visualization
Q.9 Which parameter is most critical to monitor during the expression of a recombinant protein in E. coli to avoid inclusion body formation?
pH
Dissolved oxygen
Induction temperature
Agitation speed
Explanation - Lower induction temperatures (e.g., 20‑25 °C) reduce the rate of protein synthesis, allowing proper folding and minimizing insoluble aggregates.
Correct answer is: Induction temperature
Q.10 What is the purpose of a cascade control loop in bioprocessing?
To control two variables with one sensor
To improve control speed and stability by nesting a fast inner loop within a slower outer loop
To reduce the number of sensors required
To operate without a PLC
Explanation - Cascade control uses the output of a primary controller as the set‑point for a secondary controller, enhancing response to disturbances.
Correct answer is: To improve control speed and stability by nesting a fast inner loop within a slower outer loop
Q.11 During downstream processing, ultrafiltration is primarily used for:
Removing DNA fragments
Concentrating the protein solution
Changing the buffer composition
Sterilizing the final product
Explanation - Ultrafiltration membranes retain high‑molecular‑weight proteins while allowing smaller molecules and solvents to pass, thereby concentrating the product.
Correct answer is: Concentrating the protein solution
Q.12 Which type of electrical motor is most commonly used for the impeller in large‑scale bioreactors?
Stepper motor
Servo motor
Induction motor
DC brushed motor
Explanation - Induction motors provide reliable, low‑maintenance operation and are well suited for the high torque demands of bioreactor mixing.
Correct answer is: Induction motor
Q.13 In the context of GMP (Good Manufacturing Practice), what does the term "validation" refer to?
Training personnel
Ensuring a process consistently produces product meeting its predetermined specifications
Cleaning equipment
Documenting batch records
Explanation - Validation proves that a manufacturing process yields consistent, quality‑controlled outcomes under defined conditions.
Correct answer is: Ensuring a process consistently produces product meeting its predetermined specifications
Q.14 Which analytical technique is routinely used for verifying the molecular weight of a therapeutic peptide?
High‑performance liquid chromatography (HPLC)
Mass spectrometry (MS)
UV‑Vis spectroscopy
Polarimetry
Explanation - MS accurately measures the mass‑to‑charge ratio of ions, enabling precise determination of peptide molecular weight.
Correct answer is: Mass spectrometry (MS)
Q.15 What is the main function of a pressure transducer in a sterile filtration unit?
Measure temperature of the filtrate
Detect pressure drop across the filter
Control pH of the solution
Adjust flow rate automatically
Explanation - A pressure transducer monitors the differential pressure, which indicates filter fouling or blockage during sterile filtration.
Correct answer is: Detect pressure drop across the filter
Q.16 During recombinant protein production, codon optimization is performed to:
Increase DNA stability
Reduce mRNA secondary structure
Match the host organism’s preferred codon usage for higher expression
Eliminate antibiotic resistance genes
Explanation - Optimizing codons to the host’s tRNA abundance enhances translation efficiency and protein yield.
Correct answer is: Match the host organism’s preferred codon usage for higher expression
Q.17 Which of the following is a key advantage of using a PLC (Programmable Logic Controller) over a hard‑wired relay system in bioprocess control?
Lower initial cost
Higher power handling capacity
Ease of reprogramming and scalability
Ability to operate without power
Explanation - PLCs can be reprogrammed via software, allowing quick changes to control logic without rewiring hardware.
Correct answer is: Ease of reprogramming and scalability
Q.18 In downstream purification, which step is primarily used to remove host cell DNA?
Protein A affinity chromatography
Anion‑exchange chromatography
Hydrophobic interaction chromatography
Size‑exclusion chromatography
Explanation - DNA is negatively charged and binds strongly to anion‑exchange resins, enabling its separation from the target protein.
Correct answer is: Anion‑exchange chromatography
Q.19 What is the purpose of a vent filter in a bioreactor system?
To sterilize incoming air while allowing gas exchange
To remove endotoxins from the culture medium
To adjust pH automatically
To control temperature
Explanation - Vent filters (typically 0.2 µm) prevent microbial contamination while permitting necessary gas flow for aeration.
Correct answer is: To sterilize incoming air while allowing gas exchange
Q.20 Which type of data communication protocol is commonly used for real‑time sensor data exchange in bioprocess plants?
HTTP
Modbus TCP/IP
SMTP
FTP
Explanation - Modbus TCP/IP is an industrial protocol designed for reliable, deterministic communication between PLCs and field devices.
Correct answer is: Modbus TCP/IP
Q.21 During peptide synthesis via solid‑phase synthesis, the protecting group most frequently used for the N‑terminus is:
Fmoc (9‑Fluorenylmethoxycarbonyl)
Boc (tert‑butoxycarbonyl)
Acetyl
Methyl
Explanation - Fmoc is base‑labile, allowing orthogonal deprotection steps essential for stepwise peptide assembly.
Correct answer is: Fmoc (9‑Fluorenylmethoxycarbonyl)
Q.22 What does the term "specific productivity" (qP) refer to in cell culture processes?
Amount of product formed per unit time per cell mass
Volume of medium processed per hour
Energy consumption of the bioreactor
Number of cells harvested per day
Explanation - qP = (product concentration)/(cell concentration × time) and is a key performance metric for bioprocess efficiency.
Correct answer is: Amount of product formed per unit time per cell mass
Q.23 Which of the following is an advantage of using a continuous bioprocess (perfusion) over batch cultivation for therapeutic protein production?
Higher product variability
Reduced equipment footprint
Simpler downstream processing
Longer overall production time
Explanation - Continuous processes maintain cells at steady state, requiring smaller reactors and allowing constant product harvest.
Correct answer is: Reduced equipment footprint
Q.24 In a bioprocess control system, a "dead band" is:
The range of sensor values that are ignored to prevent excessive control action
The maximum temperature the system can reach
A type of safety valve
The time delay between sensor reading and actuator response
Explanation - Dead band avoids frequent on/off switching when the process variable fluctuates around the set point.
Correct answer is: The range of sensor values that are ignored to prevent excessive control action
Q.25 Which software tool is most commonly used for designing and simulating control loops in bioprocess engineering?
MATLAB/Simulink
AutoCAD
Microsoft Excel
SolidWorks
Explanation - MATLAB/Simulink provides a powerful environment for modeling dynamic systems, including PID tuning for bioprocesses.
Correct answer is: MATLAB/Simulink
Q.26 During the purification of a peptide, why is a reversed‑phase HPLC column typically used?
To separate based on charge
To exploit hydrophobic interactions for high resolution separation
To remove endotoxins
To adjust pH of the product
Explanation - Reversed‑phase HPLC separates molecules according to hydrophobicity, which is ideal for small peptides.
Correct answer is: To exploit hydrophobic interactions for high resolution separation
Q.27 Which of the following is a primary cause of product degradation during storage of therapeutic proteins?
High humidity
Low pH
Exposure to light (photodegradation)
All of the above
Explanation - Proteins can undergo hydrolysis, aggregation, and photodegradation; controlling humidity, pH, and light exposure is essential for stability.
Correct answer is: All of the above
Q.28 In an industrial setting, what is the role of a ‘batch record’?
A document that records each step, parameter, and deviation for a manufacturing batch
A list of raw material suppliers
A training manual for operators
A financial statement
Explanation - Batch records provide traceability and are required for regulatory compliance in therapeutic protein production.
Correct answer is: A document that records each step, parameter, and deviation for a manufacturing batch
Q.29 Which type of filtration is used to achieve a 0.2 µm sterility filter for the final drug product?
Microfiltration
Ultrafiltration
Nanofiltration
Dialysis
Explanation - Microfiltration membranes with a pore size of 0.2 µm are standard for sterile filtration of liquids.
Correct answer is: Microfiltration
Q.30 What is the purpose of using a ‘design of experiments’ (DoE) approach in process development?
To test one factor at a time
To systematically explore multiple variables and their interactions
To reduce the number of experiments to a single run
To replace all analytical testing
Explanation - DoE enables efficient optimization by studying the combined effect of several process parameters.
Correct answer is: To systematically explore multiple variables and their interactions
Q.31 In a bioreactor, which parameter most directly influences oxygen transfer rate (OTR)?
Impeller speed
pH set point
Temperature
Medium viscosity
Explanation - Higher agitation improves gas-liquid mass transfer, increasing OTR.
Correct answer is: Impeller speed
Q.32 What is the main function of a ‘kill‑step’ in downstream processing of viral vectors?
Inactivate any residual host cells
Remove endotoxins
Concentrate the viral particles
Adjust pH for formulation
Explanation - A kill‑step (e.g., low pH or heat) ensures that any contaminating cells are inactivated, improving product safety.
Correct answer is: Inactivate any residual host cells
Q.33 Which of the following best describes the function of a ‘mass flow controller’ in a bioprocess gas delivery system?
Measure the temperature of incoming gas
Regulate the exact flow rate of gases such as oxygen or nitrogen
Convert gas pressure to voltage
Filter particulate matter from gas streams
Explanation - Mass flow controllers use closed‑loop feedback to maintain precise gas flow rates, crucial for maintaining DO levels.
Correct answer is: Regulate the exact flow rate of gases such as oxygen or nitrogen
Q.34 The term ‘scale‑up factor’ in bioprocess engineering refers to:
The ratio of product concentration between two batches
The multiplier used to convert lab‑scale parameters to pilot‑scale or commercial scale
The time needed to complete a batch
The cost increase per liter of product
Explanation - Scale‑up factor guides the adjustment of parameters like agitation speed, feed rate, and reactor volume when moving to larger scales.
Correct answer is: The multiplier used to convert lab‑scale parameters to pilot‑scale or commercial scale
Q.35 Which analytical technique is used to assess the secondary structure of a therapeutic protein?
Circular dichroism (CD) spectroscopy
Gas chromatography (GC)
Atomic absorption spectroscopy (AAS)
Fluorescence microscopy
Explanation - CD measures differential absorption of left‑ and right‑circularly polarized light, revealing alpha‑helix and beta‑sheet content.
Correct answer is: Circular dichroism (CD) spectroscopy
Q.36 In a fermentation process, what does the term ‘lag phase’ describe?
Rapid cell growth
Period of metabolic adjustment before exponential growth
Cell death due to nutrient depletion
Stationary phase where growth stops
Explanation - During lag phase, cells acclimate to the environment, synthesizing enzymes needed for division.
Correct answer is: Period of metabolic adjustment before exponential growth
Q.37 Which of the following is a common method for removing endotoxins from a protein solution?
Ion‑exchange chromatography using anion‑exchange resin
Gel filtration chromatography
Hydrophobic interaction chromatography
Size‑exclusion chromatography
Explanation - Endotoxins carry a strong negative charge and bind to anion‑exchange resins, allowing their removal.
Correct answer is: Ion‑exchange chromatography using anion‑exchange resin
Q.38 What does the abbreviation ‘PAT’ stand for in biopharmaceutical manufacturing?
Process Analytical Technology
Protein Assembly Technique
Polymerization Assessment Tool
Power Amplification Transmitter
Explanation - PAT refers to systems for real‑time monitoring and control of critical process parameters.
Correct answer is: Process Analytical Technology
Q.39 In a PLC ladder logic diagram, the symbol that looks like a pair of parallel lines represents:
A coil
A normally open contact
A normally closed contact
A timer
Explanation - Parallel lines denote a normally open (NO) contact, which closes when its associated input is true.
Correct answer is: A normally open contact
Q.40 Which factor is most important when selecting a buffer for maintaining pH during protein purification?
Viscosity of the buffer
Buffer capacity around the target pH
Electrical conductivity
Color of the buffer
Explanation - A buffer with high capacity near the desired pH resists changes caused by metabolic activity or added reagents.
Correct answer is: Buffer capacity around the target pH
Q.41 When using a peristaltic pump to deliver feed media, why is it important to calibrate the pump flow rate regularly?
To ensure the tubing does not wear out
To maintain accurate substrate delivery and avoid over‑ or under‑feeding
To keep the pump motor cool
To reduce noise in the facility
Explanation - Peristaltic pumps can drift; calibration guarantees the feed rate matches the designed feeding strategy.
Correct answer is: To maintain accurate substrate delivery and avoid over‑ or under‑feeding
Q.42 What is the primary purpose of a ‘clean‑in‑place’ (CIP) system in a bioprocess plant?
To sterilize the product after filling
To clean equipment without disassembly, using circulating cleaning solutions
To monitor temperature in real time
To control gas flow to the bioreactor
Explanation - CIP automates cleaning cycles, reducing downtime and contamination risk.
Correct answer is: To clean equipment without disassembly, using circulating cleaning solutions
Q.43 In the context of bioprocess monitoring, a ‘soft sensor’ refers to:
A virtual sensor that estimates a variable using mathematical models and existing measurements
A low‑cost hardware sensor
A sensor used only during development
A sensor that measures temperature only
Explanation - Soft sensors combine process data and algorithms to infer hard‑to‑measure parameters, such as biomass concentration.
Correct answer is: A virtual sensor that estimates a variable using mathematical models and existing measurements
Q.44 Which of the following is a typical cause of shear‑induced damage to mammalian cells in a bioreactor?
High impeller speed
Low pH
Excessive temperature
Insufficient CO₂ supply
Explanation - Excessive agitation can generate shear forces that disrupt cell membranes, reducing viability.
Correct answer is: High impeller speed
Q.45 What is the main benefit of using a ‘single‑use’ (SU) chromatography column over a stainless‑steel column?
Higher pressure tolerance
Reduced cross‑contamination risk and elimination of cleaning validation
Longer lifespan
Lower purchase price
Explanation - SU columns are disposable, which avoids cleaning steps and minimizes risk of residual contaminants.
Correct answer is: Reduced cross‑contamination risk and elimination of cleaning validation
Q.46 During the final formulation of a therapeutic peptide, lyophilization is performed to:
Increase the peptide’s molecular weight
Remove water and improve stability for storage
Sterilize the product by heat
Change the peptide’s primary structure
Explanation - Lyophilization (freeze‑drying) creates a dry powder, enhancing shelf‑life and ease of reconstitution.
Correct answer is: Remove water and improve stability for storage
Q.47 Which type of electrode is commonly used for measuring dissolved oxygen in bioreactors?
Polarographic electrode
pH electrode
Ion‑selective electrode
Thermocouple
Explanation - Polarographic DO sensors use a membrane‑covered cathode and anode to generate a current proportional to oxygen concentration.
Correct answer is: Polarographic electrode
Q.48 In a downstream purification train, what is the typical order of operations for a monoclonal antibody?
Protein A affinity → Ion exchange → Viral filtration → Ultrafiltration
Ion exchange → Protein A affinity → Size exclusion → Sterile filtration
Hydrophobic interaction → Protein A affinity → Gel filtration → Reverse osmosis
Gel filtration → Hydrophobic interaction → Protein A affinity → Nanofiltration
Explanation - The standard sequence captures the antibody, removes impurities, ensures viral safety, and concentrates the product.
Correct answer is: Protein A affinity → Ion exchange → Viral filtration → Ultrafiltration
Q.49 What does the term ‘half‑life’ refer to in the context of a therapeutic protein’s pharmacokinetics?
Time required for the protein to reach maximum concentration
Time needed for the drug to be completely eliminated
Time for the plasma concentration to decrease by 50 %
Time required for the protein to fold correctly
Explanation - Half‑life is a key PK parameter indicating how long a drug stays active in the body.
Correct answer is: Time for the plasma concentration to decrease by 50 %
Q.50 Which of the following statements about ‘glycosylation’ of therapeutic proteins is correct?
It has no impact on protein stability
It can affect efficacy, immunogenicity, and half‑life
It occurs only in bacterial expression systems
It is always undesirable
Explanation - Glycosylation patterns influence protein function and are critical for biologics produced in mammalian cells.
Correct answer is: It can affect efficacy, immunogenicity, and half‑life
Q.51 In a bioreactor, the ‘kLa’ value is a measure of:
Heat transfer coefficient
Oxygen transfer coefficient
pH buffering capacity
Viscosity of the medium
Explanation - kLa quantifies the rate at which oxygen dissolves into the liquid phase, a key factor for aerobic cultures.
Correct answer is: Oxygen transfer coefficient
Q.52 Which of the following is NOT a typical attribute monitored by an online Raman spectroscopy system in a bioprocess?
Metabolite concentrations
Cell density
pH
Temperature
Explanation - Raman provides molecular fingerprint data for metabolites and cell components, but temperature is measured by separate sensors.
Correct answer is: Temperature
Q.53 When scaling up a stirred‑tank bioreactor, maintaining constant impeller tip speed helps preserve:
Shear environment
pH profile
Temperature gradient
Osmolality
Explanation - Tip speed directly influences shear forces experienced by cells, crucial for cell viability during scale‑up.
Correct answer is: Shear environment
Q.54 Which type of chromatography is most suitable for separating peptides based on charge differences at a given pH?
Affinity chromatography
Ion‑exchange chromatography
Size‑exclusion chromatography
Hydrophobic interaction chromatography
Explanation - IEX exploits the net charge of peptides at a set pH to retain and separate them on charged resins.
Correct answer is: Ion‑exchange chromatography
Q.55 What is the primary function of a ‘check valve’ in a liquid feed line of a bioprocess?
To regulate flow rate
To prevent backflow of media
To measure pressure
To filter contaminants
Explanation - Check valves allow flow in one direction only, protecting pumps and preventing contamination.
Correct answer is: To prevent backflow of media
Q.56 Which of the following is a common cause of product loss during ultrafiltration concentration steps?
Membrane fouling leading to product adsorption
Excessive temperature
Low pH
High agitation speed
Explanation - Fouled membranes can retain product on their surface, reducing overall recovery.
Correct answer is: Membrane fouling leading to product adsorption
Q.57 In a batch record, the term ‘deviation’ refers to:
A planned change to the process
An unexpected departure from the approved procedure
A routine cleaning step
A scheduled maintenance activity
Explanation - Deviations must be documented, investigated, and possibly impact product release.
Correct answer is: An unexpected departure from the approved procedure
Q.58 Which of the following is a major advantage of using a continuous‑flow centrifuge for cell harvesting?
Higher shear forces
Lower capital cost
Higher throughput and reduced residence time
Ability to separate DNA
Explanation - Continuous centrifuges can process large volumes quickly, minimizing cell stress and improving yield.
Correct answer is: Higher throughput and reduced residence time
Q.59 What does the abbreviation ‘Biosafety Level 2 (BSL‑2)’ indicate about a manufacturing facility?
It handles only chemical hazards
It processes agents that pose moderate potential hazards to personnel
It can produce only non‑living products
It is a cleanroom class ISO 1
Explanation - BSL‑2 labs handle agents that can cause human disease but are not easily transmissible, requiring specific containment measures.
Correct answer is: It processes agents that pose moderate potential hazards to personnel
Q.60 During downstream processing, the purpose of a ‘viral clearance step’ is to:
Increase product concentration
Remove residual host cell proteins
Eliminate potential viral contaminants
Adjust pH
Explanation - Viral clearance methods (e.g., nanofiltration, low pH treatment) ensure safety of biologics by removing viruses.
Correct answer is: Eliminate potential viral contaminants
Q.61 Which of the following is a typical indicator of cell lysis in a fermentation broth?
Decrease in dissolved oxygen
Increase in extracellular DNA concentration
Rise in temperature
Drop in agitation speed
Explanation - When cells lyse, intracellular DNA is released into the broth, measurable as an indicator of cell integrity loss.
Correct answer is: Increase in extracellular DNA concentration
Q.62 What is the main reason for using a ‘dual‑sensor’ (pH and temperature) probe in a bioreactor?
To reduce the number of cables
To simultaneously monitor two critical parameters with a single insertion point
To increase the probe’s lifespan
To provide redundancy for each measurement
Explanation - Dual‑sensor probes simplify installation and provide real‑time data for both pH and temperature, which are tightly coupled.
Correct answer is: To simultaneously monitor two critical parameters with a single insertion point
Q.63 In the context of bioprocess automation, ‘HMI’ stands for:
Human‑Machine Interface
High‑Medium Integration
Hydraulic Motor Indicator
Hybrid Monitoring Instrument
Explanation - HMI provides operators with graphical displays to monitor and control processes.
Correct answer is: Human‑Machine Interface
Q.64 Which factor most directly influences the solubility of a protein during purification?
pH of the buffer
Color of the solution
Magnetic field strength
Ambient lighting
Explanation - Protein solubility is highly pH‑dependent; moving away from the isoelectric point improves solubility.
Correct answer is: pH of the buffer
Q.65 What is the primary purpose of adding a ‘cryoprotectant’ such as sucrose before freeze‑drying a protein product?
To increase the product’s pH
To protect protein structure from freeze‑induced stress
To sterilize the product
To accelerate drying
Explanation - Cryoprotectants prevent ice crystal formation that can denature proteins during freezing.
Correct answer is: To protect protein structure from freeze‑induced stress
Q.66 In a fed‑batch process, the ‘feed‑forward’ control strategy uses:
Real‑time measurements of DO to adjust feed rate
Predetermined feed schedule based on model predictions
Random feed addition
Feedback from product concentration
Explanation - Feed‑forward control anticipates needs by using process models rather than waiting for sensor feedback.
Correct answer is: Predetermined feed schedule based on model predictions
Q.67 Which analytical method is typically used to determine the aggregate content of a therapeutic protein?
Dynamic Light Scattering (DLS)
Fourier‑Transform Infrared (FTIR) spectroscopy
Nuclear Magnetic Resonance (NMR)
Electrophoretic mobility shift assay
Explanation - DLS measures particle size distribution, enabling detection of protein aggregates.
Correct answer is: Dynamic Light Scattering (DLS)
Q.68 When designing a bioprocess for a peptide therapeutic, which of the following is a key consideration for downstream purification?
Peptide hydrophobicity
Cell wall thickness
Oxygen solubility
Impeller blade shape
Explanation - Peptide hydrophobicity dictates the choice of chromatography (e.g., reversed‑phase) for effective separation.
Correct answer is: Peptide hydrophobicity
Q.69 What does the term ‘process robustness’ refer to in biomanufacturing?
The ability of a process to produce consistent product quality despite variability in raw materials or operating conditions
The speed at which a process can be completed
The cost of raw materials
The number of staff required
Explanation - Robust processes tolerate disturbances without compromising product quality, essential for regulatory compliance.
Correct answer is: The ability of a process to produce consistent product quality despite variability in raw materials or operating conditions
Q.70 In an electro‑pneumatic valve used for gas control, the term ‘solenoid’ refers to:
The mechanical spring that opens the valve
The electromagnetic coil that moves the valve spool
A type of sensor for pressure
A safety interlock
Explanation - A solenoid converts electrical energy into linear motion, actuating the valve.
Correct answer is: The electromagnetic coil that moves the valve spool
Q.71 Which of the following is the most appropriate method for determining the endotoxin level in a final biologic product?
Limulus Amebocyte Lysate (LAL) assay
ELISA for protein concentration
HPLC for peptide purity
Gravimetric analysis
Explanation - LAL detects endotoxin via clotting of horseshoe crab blood components, providing a sensitive quantification method.
Correct answer is: Limulus Amebocyte Lysate (LAL) assay
Q.72 Which factor most directly influences the selection of a stainless‑steel grade for bioreactor construction?
Magnetic properties
Corrosion resistance and compatibility with cleaning agents
Electrical conductivity
Color
Explanation - 316L stainless steel offers high corrosion resistance and is suitable for repeated CIP/SIP cycles.
Correct answer is: Corrosion resistance and compatibility with cleaning agents
Q.73 In the context of protein therapeutics, the term ‘Fc‑fusion’ indicates:
A protein fused to the constant region of an antibody to extend half‑life
A method of attaching a fluorophore
A type of peptide bond cleavage
A technique for DNA sequencing
Explanation - Fc‑fusion proteins leverage the neonatal Fc receptor recycling pathway for prolonged circulation.
Correct answer is: A protein fused to the constant region of an antibody to extend half‑life
Q.74 What is the primary function of a ‘mixing tank’ upstream of a chromatography column?
To sterilize the feed solution
To adjust buffer composition and temperature before loading
To remove particulate matter
To compress the sample
Explanation - Mixing tanks ensure that the sample matches the column’s buffer conditions, preventing column shock.
Correct answer is: To adjust buffer composition and temperature before loading
Q.75 Which of the following best describes a ‘non‑linear’ PID controller?
A controller that only uses proportional gain
A controller where the relationship between error and output is not directly proportional
A controller without integral action
A controller that operates at a fixed set point
Explanation - Non‑linear PID controllers apply gain schedules or functions to adapt to varying process dynamics.
Correct answer is: A controller where the relationship between error and output is not directly proportional
Q.76 In the production of a therapeutic peptide, which unit operation is most likely to introduce racemization of amino acids?
Solid‑phase synthesis coupling step at high temperature
Ultrafiltration
Ion‑exchange chromatography
Lyophilization
Explanation - Elevated temperature during coupling can cause partial racemization of chiral centers in amino acids.
Correct answer is: Solid‑phase synthesis coupling step at high temperature
Q.77 Which regulatory guideline specifically addresses the validation of aseptic processing for biopharmaceuticals?
ISO 9001
ICH Q7
USP <797>
GMP 21 CFR Part 11
Explanation - USP <797> provides standards for sterile compounding and aseptic processing.
Correct answer is: USP <797>
Q.78 What is the purpose of a ‘turbidity sensor’ in a bioprocessing line?
To measure dissolved oxygen
To detect cell density or particle load in the liquid
To control temperature
To monitor pH
Explanation - Turbidity correlates with suspended solids; it can be used for real‑time cell concentration monitoring.
Correct answer is: To detect cell density or particle load in the liquid
Q.79 During the expression of a recombinant protein in CHO cells, which supplement is often added to the medium to enhance glycosylation?
Maltose
Manganese chloride
Sodium bicarbonate
Glucose
Explanation - Manganese acts as a co‑factor for glycosyltransferases, improving glycan formation.
Correct answer is: Manganese chloride
Q.80 Which of the following statements about ‘single‑use’ (SU) bioreactors is FALSE?
They reduce cross‑contamination risk.
They eliminate the need for cleaning validation.
They can handle very high pressures above 10 MPa.
They are typically made from polymeric materials.
Explanation - SU reactors are limited in pressure tolerance compared to stainless steel vessels; high pressures are generally unsuitable.
Correct answer is: They can handle very high pressures above 10 MPa.
Q.81 In a bioprocess, the term ‘critical quality attribute’ (CQA) refers to:
A raw material impurity
A property of the product that must be within a specific range to ensure safety and efficacy
A piece of equipment that is critical to operation
A standard operating procedure
Explanation - CQAs are defined during development and are monitored throughout manufacturing.
Correct answer is: A property of the product that must be within a specific range to ensure safety and efficacy
Q.82 Which of the following is a common cause of foaming in a bioreactor and must be controlled?
Low agitation speed
High dissolved oxygen
Presence of surfactants or proteins in the medium
Low temperature
Explanation - Proteins and surfactants lower surface tension, promoting foam formation that can cause overflow.
Correct answer is: Presence of surfactants or proteins in the medium
Q.83 When performing a risk assessment for a biopharmaceutical process, the ‘FMEA’ methodology stands for:
Failure Modes and Effects Analysis
Fast Molecular Evaluation Algorithm
Fermentation Monitoring and Evaluation
Functional Mechanical Engineering Assessment
Explanation - FMEA identifies potential failure points, their causes, and impacts to prioritize mitigation strategies.
Correct answer is: Failure Modes and Effects Analysis
Q.84 What is the typical pore size of a sterile‑filter membrane used for final drug product filtration?
0.45 µm
1.0 µm
0.2 µm
5 µm
Explanation - A 0.2 µm membrane effectively removes bacteria, achieving sterility for injectable products.
Correct answer is: 0.2 µm
Q.85 In bioprocess data acquisition, a ‘sampling rate’ of 1 Hz means:
Data is collected once every hour
Data is collected once per second
Data is collected once per minute
Data is collected once per day
Explanation - 1 Hz equals one sample per second, providing real‑time monitoring.
Correct answer is: Data is collected once per second
Q.86 Which of the following is an advantage of using a 'modular' bioprocessing platform?
Fixed capacity that cannot be altered
Rapid reconfiguration for different products
Higher energy consumption
Increased manual labor
Explanation - Modular systems consist of interchangeable units, allowing quick changes between production campaigns.
Correct answer is: Rapid reconfiguration for different products
Q.87 When measuring protein concentration by UV absorbance at 280 nm, the extinction coefficient depends primarily on the presence of:
Tryptophan and tyrosine residues
Serine and threonine residues
Glycine residues
Cysteine residues
Explanation - These aromatic amino acids have strong absorbance at 280 nm, defining the extinction coefficient.
Correct answer is: Tryptophan and tyrosine residues
Q.88 In a bioprocess, the term ‘off‑gas analysis’ typically refers to monitoring:
CO₂ and O₂ concentrations in the exhaust gas
The pH of the culture medium
The temperature of the bioreactor
The conductivity of the feed solution
Explanation - Off‑gas analyzers track respiratory gases to infer metabolic activity and adjust aeration.
Correct answer is: CO₂ and O₂ concentrations in the exhaust gas
Q.89 Which of the following is a typical method for removing host cell DNA from a protein product?
Anion‑exchange chromatography
Hydrophobic interaction chromatography
Gel filtration
Affinity chromatography
Explanation - DNA's negative charge makes it bind strongly to anion‑exchange resins, allowing separation from the protein.
Correct answer is: Anion‑exchange chromatography
Q.90 What does the term ‘batch‑to‑batch variation’ describe in biomanufacturing?
Differences in equipment size between batches
Variability in product quality attributes from one production run to another
Changes in the number of operators
Variations in the color of the final product
Explanation - Consistent batch performance is crucial for regulatory approval; high variation may indicate process instability.
Correct answer is: Variability in product quality attributes from one production run to another
Q.91 Which of the following best describes the purpose of a ‘cleanroom classification’ such as ISO 7?
Defines the number of personnel allowed in the room
Specifies the maximum allowable airborne particle concentration
Indicates the temperature range of the room
Sets the required lighting intensity
Explanation - ISO cleanroom classes define limits for particles ≥0.5 µm per cubic meter of air, ensuring product sterility.
Correct answer is: Specifies the maximum allowable airborne particle concentration
Q.92 In a continuous‑flow chromatography system, the term ‘residence time’ refers to:
The time it takes for a column to be cleaned
The duration a solute spends within the column
The time required to sterilize the system
The interval between two consecutive runs
Explanation - Residence time influences separation efficiency; shorter times may reduce resolution.
Correct answer is: The duration a solute spends within the column
Q.93 Which of the following is a common method for verifying the sterility of a final biologic product?
Incubation of product samples in growth media for a specified period
Measuring product pH
Conductivity testing
Visual inspection for turbidity
Explanation - Sterility testing involves inoculating media and observing for microbial growth over 14‑28 days.
Correct answer is: Incubation of product samples in growth media for a specified period
Q.94 What is the primary advantage of using a ‘nanofilter’ (≤20 nm pore size) in viral clearance?
Removal of endotoxins
Removal of sub‑viral particles and viruses while allowing proteins to pass
Increasing product concentration
Adjusting pH of the solution
Explanation - Nanofiltration retains viruses based on size exclusion but does not significantly retain therapeutic proteins.
Correct answer is: Removal of sub‑viral particles and viruses while allowing proteins to pass
Q.95 During a cell‑culture process, a sudden drop in dissolved oxygen without a change in air flow suggests:
Sensor failure
Increased cell density and oxygen consumption
Decrease in temperature
Increase in pH
Explanation - Higher biomass consumes more oxygen, causing a DO drop if aeration is unchanged.
Correct answer is: Increased cell density and oxygen consumption
Q.96 Which type of control loop is commonly employed to maintain a bioreactor’s temperature within ±0.1 °C?
On‑off control
PID control
Feed‑forward control
Cascade control
Explanation - PID provides precise temperature regulation by continuously adjusting heating/cooling based on error signals.
Correct answer is: PID control
Q.97 In the context of GMP documentation, a ‘master batch record’ (MBR) is used for:
Recording raw material deliveries
Defining the standard procedures for a specific product batch
Training new employees
Tracking equipment maintenance
Explanation - The MBR outlines the approved steps, parameters, and controls for manufacturing a particular product.
Correct answer is: Defining the standard procedures for a specific product batch
Q.98 Which of the following best explains why temperature control is critical during protein crystallization steps?
Temperature influences the solubility and nucleation rate of the protein
Temperature changes the color of the solution
Temperature controls the pH directly
Temperature affects the magnetic field of the equipment
Explanation - Precise temperature control ensures consistent crystal growth and desired polymorph formation.
Correct answer is: Temperature influences the solubility and nucleation rate of the protein
Q.99 Which analytical technique is most suitable for quantifying the concentration of a peptide in a complex mixture?
High‑performance liquid chromatography (HPLC) with UV detection
Gas chromatography (GC)
Atomic absorption spectroscopy (AAS)
Electrocardiography (ECG)
Explanation - HPLC separates peptides and, coupled with UV detection, provides accurate quantitation even in complex matrices.
Correct answer is: High‑performance liquid chromatography (HPLC) with UV detection
Q.100 In a bioprocess, the term ‘harvest’ refers to:
The moment when the reactor reaches maximum temperature
The removal of the cell culture broth from the bioreactor for downstream processing
The cleaning of the bioreactor after the run
The addition of feed media
Explanation - Harvesting collects the bulk product (cells, supernatant) for further purification.
Correct answer is: The removal of the cell culture broth from the bioreactor for downstream processing
Q.101 Which type of bioreactor agitator is most suitable for shear‑sensitive mammalian cells?
Rushton turbine
Marine impeller
Pitch‑blade impeller
High‑speed axial flow impeller
Explanation - Pitch‑blade impellers provide gentle mixing with lower shear forces, preserving delicate cells.
Correct answer is: Pitch‑blade impeller
Q.102 What is the primary reason for performing a ‘process analytical technology’ (PAT) assessment during process development?
To reduce the number of required staff
To integrate real‑time measurements that enable proactive control of critical process parameters
To increase the size of the bioreactor
To replace all downstream steps
Explanation - PAT provides insight and control during manufacturing, improving product quality and consistency.
Correct answer is: To integrate real‑time measurements that enable proactive control of critical process parameters
Q.103 Which of the following is a common source of metal ion contamination in protein therapeutics?
Stainless steel piping
Silicone tubing
Glass containers
Plastic caps
Explanation - Corrosion or leaching from steel can introduce trace metal ions, affecting protein stability.
Correct answer is: Stainless steel piping
Q.104 In a bioprocess, a ‘scale‑down model’ is used to:
Increase production capacity
Mimic large‑scale conditions on a smaller, more manageable platform for experimentation
Reduce the need for cleaning
Eliminate the need for sensors
Explanation - Scale‑down models allow rapid testing of parameters before committing to full‑scale production.
Correct answer is: Mimic large‑scale conditions on a smaller, more manageable platform for experimentation
Q.105 Which of the following is the most appropriate method for monitoring cell viability in a mammalian cell culture?
Trypan blue exclusion assay
Measuring pH
Measuring dissolved oxygen
Measuring conductivity
Explanation - Viable cells exclude trypan blue dye, allowing direct counting of live versus dead cells.
Correct answer is: Trypan blue exclusion assay
Q.106 When designing a control algorithm for a bioreactor, which of the following is a typical ‘disturbance’ that the system must compensate for?
Change in ambient room temperature
Adjustment of the set point by the operator
Scheduled maintenance
Software update
Explanation - External temperature shifts can affect the bioreactor’s internal temperature, requiring compensation.
Correct answer is: Change in ambient room temperature
Q.107 Which of the following best describes a ‘closed‑system’ bioreactor?
A reactor with a transparent lid for visual inspection
A system where all connections are sterile and the culture is not exposed to the environment
A reactor that uses open air for aeration
A system that operates without any sensors
Explanation - Closed systems maintain sterility by preventing exposure to external contaminants.
Correct answer is: A system where all connections are sterile and the culture is not exposed to the environment
Q.108 In the manufacturing of a therapeutic protein, the term ‘glyco‑engineering’ refers to:
Altering the amino acid sequence to improve solubility
Modifying the carbohydrate structures attached to the protein to influence its properties
Changing the protein’s secondary structure
Engineering the gene promoter
Explanation - Glyco‑engineering tailors glycan patterns to improve efficacy, stability, and half‑life.
Correct answer is: Modifying the carbohydrate structures attached to the protein to influence its properties
Q.109 Which type of sensor would you use to monitor the pressure inside a high‑pressure sterilization (SIP) vessel?
Thermocouple
Capacitive pressure sensor
pH electrode
Flow meter
Explanation - Capacitive sensors accurately measure high pressures and are compatible with sterilization conditions.
Correct answer is: Capacitive pressure sensor
Q.110 In a downstream purification train, the purpose of a ‘viral inactivation’ step is to:
Increase product concentration
Remove host cell proteins
Eliminate any potential viral contaminants
Adjust pH of the product
Explanation - Viral inactivation (e.g., low pH treatment) ensures product safety by destroying residual viruses.
Correct answer is: Eliminate any potential viral contaminants
Q.111 Which of the following is the most common type of membrane used for ultrafiltration of therapeutic proteins?
Polyethersulfone (PES)
Polyvinyl chloride (PVC)
Nylon
Cellulose acetate
Explanation - PES membranes offer high flux, chemical resistance, and low protein binding, ideal for protein UF.
Correct answer is: Polyethersulfone (PES)
Q.112 In a fed‑batch process, the term ‘exponential feeding’ means:
Feeding substrate at a constant rate
Increasing the feed rate exponentially over time to match cell growth
Stopping feed after a set time
Feeding only when DO drops
Explanation - Exponential feeding aligns substrate supply with the exponential increase in cell biomass.
Correct answer is: Increasing the feed rate exponentially over time to match cell growth
Q.113 Which of the following best describes a ‘critical process parameter’ (CPP) in biomanufacturing?
A variable that can affect the critical quality attributes of the product and must be controlled
A documentation form
A type of raw material impurity
A piece of equipment
Explanation - CPPs are monitored and controlled to ensure CQAs remain within specification.
Correct answer is: A variable that can affect the critical quality attributes of the product and must be controlled
Q.114 During lyophilization, the primary drying phase removes:
Bound water through sublimation
Free water by evaporation
All moisture via boiling
Residual solvents
Explanation - Primary drying (sublimation) removes ice directly as vapor, leaving the product in a dry, porous state.
Correct answer is: Bound water through sublimation
Q.115 Which regulatory agency is responsible for approving biologic therapeutics in the United States?
EMA
FDA
WHO
MHRA
Explanation - The U.S. Food and Drug Administration (FDA) oversees the approval of biologics through the Center for Biologics Evaluation and Research (CBER).
Correct answer is: FDA
Q.116 What is the main benefit of using a ‘digital twin’ model in bioprocess development?
Physical replication of the plant
A virtual replica that enables simulation of process changes without risking real batches
Automatic cleaning of equipment
Real‑time video monitoring
Explanation - Digital twins allow rapid testing of scenarios, reducing time and cost associated with physical trials.
Correct answer is: A virtual replica that enables simulation of process changes without risking real batches
Q.117 When a protein therapeutic is stored at 2‑8 °C, the main degradation pathway that must be monitored is:
Oxidation
Thermal denaturation
Hydrolysis
Photodegradation
Explanation - Even at refrigerated temperatures, oxidation of methionine, tryptophan, and cysteine residues can occur over time.
Correct answer is: Oxidation
Q.118 In an upstream bioprocess, what does the term ‘cell density’ usually refer to?
Number of cells per unit volume (e.g., cells/mL)
Weight of the bioreactor
Volume of the medium
pH of the culture
Explanation - Cell density is a key metric indicating the concentration of viable cells in the culture.
Correct answer is: Number of cells per unit volume (e.g., cells/mL)
Q.119 Which of the following is a common approach to increase the expression level of a recombinant protein in a bacterial host?
Using a weaker promoter
Lowering the incubation temperature during induction
Increasing the plasmid copy number
Adding excess antibiotics
Explanation - More copies of the gene per cell can boost transcription and translation, raising protein yield.
Correct answer is: Increasing the plasmid copy number
Q.120 During downstream processing, the term ‘load’ refers to:
The amount of feed media added to the bioreactor
The quantity of protein solution applied to a chromatography column per run
The number of operators working on the line
The pressure applied to a filter
Explanation - Load determines column capacity and influences breakthrough and product recovery.
Correct answer is: The quantity of protein solution applied to a chromatography column per run
Q.121 Which analytical technique is most suitable for detecting post‑translational modifications (PTMs) such as phosphorylation on a therapeutic protein?
Mass spectrometry (MS)
UV‑Vis spectroscopy
Conductivity measurement
Refractometry
Explanation - MS can precisely identify mass shifts corresponding to PTMs like phosphorylation, acetylation, etc.
Correct answer is: Mass spectrometry (MS)
Q.122 In the context of bioprocessing, the abbreviation ‘SIP’ stands for:
Sterile In‑Process
Steam‑In‑Place
Signal Integration Protocol
Standard Inspection Procedure
Explanation - SIP uses steam to sterilize equipment and piping without disassembly.
Correct answer is: Steam‑In‑Place
Q.123 Which of the following best describes the purpose of a ‘process validation’ study?
To confirm that a manufacturing process reliably produces a product meeting its predetermined specifications
To train staff on new equipment
To design the layout of the facility
To calculate the cost of raw materials
Explanation - Process validation provides evidence that the process is reproducible and under control.
Correct answer is: To confirm that a manufacturing process reliably produces a product meeting its predetermined specifications
Q.124 When using a peristaltic pump, why is it important to select tubing with the correct inner diameter?
To control the flow rate accurately
To reduce electrical noise
To increase the temperature of the fluid
To improve visual appearance
Explanation - Flow rate is directly proportional to the tubing’s inner diameter; incorrect size leads to inaccurate dosing.
Correct answer is: To control the flow rate accurately
Q.125 Which of the following is a key advantage of using a ‘continuous‑perfusion’ system for mammalian cell culture?
Higher cell viability due to removal of waste metabolites and constant nutrient supply
Lower capital cost
Simpler equipment design
Elimination of need for sterility
Explanation - Perfusion continuously supplies fresh media and removes waste, sustaining high cell densities and viability.
Correct answer is: Higher cell viability due to removal of waste metabolites and constant nutrient supply
Q.126 In a chromatographic separation, the term ‘binding capacity’ refers to:
The maximum amount of target protein that can be adsorbed onto the resin before breakthrough occurs
The speed at which the column operates
The pH range of the mobile phase
The temperature of the column
Explanation - Binding capacity determines how much product can be loaded onto a column before the resin becomes saturated.
Correct answer is: The maximum amount of target protein that can be adsorbed onto the resin before breakthrough occurs
Q.127 What is the primary purpose of a ‘filter integrity test’ after sterile filtration?
To verify that the filter has not been damaged and still provides a 0.2 µm barrier
To measure the pH of the filtrate
To calibrate the pressure sensor
To determine the filter’s color
Explanation - Integrity testing (e.g., bubble point) confirms the filter remains intact and functional.
Correct answer is: To verify that the filter has not been damaged and still provides a 0.2 µm barrier
Q.128 Which of the following is the most suitable method for measuring the viscosity of a high‑cell‑density culture broth?
Rheometer
pH meter
Refractometer
Spectrophotometer
Explanation - A rheometer directly measures shear stress and strain, providing accurate viscosity data for complex fluids.
Correct answer is: Rheometer