Category: Drug & Pharmaceutical Biotechnology Objective Questions

Drug Biotechnology Multiple Choice Questions on “Mechanisms of Drug Absorption”.

1. Which is the major process of absorption for more than 90% of drugs?
a) Facilitated diffusion
b) Active transport
c) Endocytosis
d) Passive diffusion
Answer: d
Clarification: Passive diffusion is also known as non-ionic diffusion. It is the major process through which 90% of the drugs get absorbed. The driving force for passive diffusion is the concentration gradient and electrochemical gradient.

2. What is the driving force for Passive Diffusion?
a) Concentration gradient only
b) Electrochemical gradient only
c) Charge equilibration and concentration gradient
d) Concentration and Electrochemical gradient both
Answer: d
Clarification: Passive diffusion, the driving forces are both concentration gradient and electrochemical gradient. According to Fick’s first law of diffusion, drug molecules always diffuse from the site of higher concentration to the site of lower concentration until equilibrium is attained.

3. Which kind of molecules cannot pass through a pore transport?
a) Low Molecular weight molecules
b) Water-soluble drugs
c) Molecules up to 400 Dalton
d) Molecules greater than 400 Dalton
Answer: d
Clarification: Pore transport is important for the absorption of low molecular weight and size molecules. Water-soluble drugs can also easily pass through the aqueous filled spaces or pores in the cell membrane. Linear molecules of size up to 400 Dalton can be absorbed.

4. What is the driving force of Pore Transport?
a) Hydrostatic pressure
b) Concertation Gradient
c) Electrochemical gradient
d) Charge equilibration
Answer: a
Clarification: The driving force of pore transport is Hydrostatic pressure and Osmotic pressure across the cell membrane. Electrochemical gradient and concentration gradient is the driving force of passive diffusion.

5. What will be the best definition for “carrier”?
a) Nonpolar drugs can be transported through carrier-mediated transport
b) Carrier binds reversibly and no covalently with the molecules
c) It discharges the molecules and gets destroyed itself
d) The carrier is a protein
Answer: b
Clarification: The carrier-solute complex can cross the membrane to reach the other site where the carrier discharges the solute and returns back to its position. The carriers carry polar charged molecules and are mostly enzymes.

6. What is the major difference between Facilitated diffusion and Passive diffusion?
a) Carrier-mediated transport
b) Downhill transport
c) Energy is used
d) Inhibition by metabolic poisons
Answer: a
Clarification: Facilitated diffusion is a carrier-mediated transport which operates down the concentration gradient. It is faster than passive diffusion because of the involvement of Carriers. The driving force is the concentration gradient.

7. What influences the permeation of drugs in an Ionic or Electrochemical diffusion?
a) Charge on the membrane
b) Charge on the particle
c) Concentration gradient
d) Equilibration of charge
Answer: a
Clarification: The charge on the membrane influences the permeation of drugs. The permeation of positively charged drugs depends on the potential difference or electrical gradient as the driving force across the membrane.

8. Which kind of drugs are absorbed through endocytosis?
a) Molecular weight ranging 100-400Dalton
b) Water-soluble drugs
c) Macromolecular drugs or drugs as oily droplets
d) Polar drugs
Answer: c
Clarification: Macromolecular drugs, Drugs as solid particles and drugs as oily particles are absorbed through endocytosis. Passive diffusion helps in the absorption of drugs with molecular size fro 100-400 Dalton.

9. Which drugs are absorbed through pore transport?
a) High lipophilicity
b) Water-soluble drugs of molecular weight less than 100 Dalton
c) Oily droplets
d) Affinity for carriers
Answer: b
Clarification: Pore transport helps in the transport of water-soluble drugs which are of molecular weight less than 100 Dalton. Drugs with high lipophilicity and a molecular weight between 100-400 Dalton are transported by Passive diffusion.

10. Which types of drugs get absorbed by ion-pair transport?
a) High lipophilicity
b) Oily droplets
c) Affinity for carriers
d) Drugs that ionize at all pH conditions
Answer: d
Clarification: Ion-Pair Transport is the mechanism where absorption of drugs like quaternary ammonium compounds, sulphonic acids get absorbed. These drugs can get ionize at all pH conditions. These neutral complexes have lipophilicity and aqueous solubility for passive diffusion.

11. Which of these absorption methods involves engulfing of the extracellular drug?
a) Endocytosis
b) Passive diffusion
c) Facilitated diffusion
d) Ion-Pair transport
Answer: a
Clarification: Endocytosis is the absorption method which includes engulfing of extracellular materials within a segment of the cell membrane to form a saccule or vesicle which will be then pinched off intracellularly.

12. Which is the other name of “cell eating”?
a) Transcytosis
b) Phagocytosis
c) Pinocytosis
d) Endocytosis
Answer: b
Clarification: Phagocytosis is a type of endocytosis. Phagocytosis is also called cell eating which includes absorption of solid particulates. Endocytosis is of two types phagocytosis and pinocytosis later meaning cell drinking.

13. Transfer of an endocytic vesicle from one extracellular compartment to another is known as _____________
a) Phagocytosis
b) Transcytosis
c) Pinocytosis
d) Endocytosis
Answer: b
Clarification: Transfer of an endocytic vesicle from one extracellular compartment to another is known as Transcytosis. Phagocytosis is the engulfing of solid particulates. Pinocytosis is the absorption of fluids.

14. A drug can be absorbed by more than one mechanism.
a) True
b) False
Answer: a
Clarification: Yes, a drug can be absorbed by different mechanisms through different sites in the body. The mechanism depends upon the absorption site of the body. A drug can be absorbed passively and actively.

15. Which kind of absorption mechanism is showing in the following picture?

a) Endocytosis
b) Passive transport
c) Active transport
d) Facilitated diffusion
Answer: b
Clarification: Passive diffusion is a kind absorption where substances move from higher concentration to the lower concentration without the use of any carriers or energy. 90% of the drugs are absorbed through Passive diffusion.

Drug Biotechnology written test Questions & Answers on “Factors Affecting Protein Drug Binding”.

1. Which one of the following factors related to protein-drug binding is not related to drugs?
a) Physicochemical characteristics of a drug
b) The concentration of the drug in the body
c) The affinity of the drug for binding
d) Number of binding sites on the binding agent
Answer: d
Clarification: There are many factors affecting protein-drug binding. The factors related to the drug, are physicochemical characteristics of a drug, concentration of the drug in the body, affinity of the drug for binding. A number of binding sites on the binding agent are related to the protein and other binding components.

2. Which one of the following factor related to protein-drug binding is not related to drug interactions with the binding site?
a) Competition between the drug and the binding site
b) Competition between drugs and normal body constituents
c) Allosteric changes in a protein molecule
d) Inter subject variation
Answer: d
Clarification: Competition between the drug and the binding site, competition between drugs and normal body constituents, allosteric changes in protein molecule these factors are related to drug interactions. Inter subject variation is a patient-related factor.

3. Which of the following factors for protein drug binding is a drug interaction factor?
a) Competition between drugs for the binding site
b) Age
c) Physicochemical characteristics of a drug
d) Physicochemical characteristics of the protein or binding agent
Answer: a
Clarification: Physicochemical interaction is not a drug interaction factor. Competition between the drug and the binding site and competition between drug and other normal body constituents, allosteric changes in protein molecule all these factors are related to drug interaction with the protein. Age is a patient-related factor.

4. Which drugs bind to HSA easily?
a) Cationic drug
b) Anionic drug
c) Lipophilic drug
d) Neutral drug
Answer: b
Clarification: Anionic or acidic drugs bind to HSA easily, for example, penicillin and sulphonamides. Cationic or basic drugs bind easily to alpha 1 acid glycoprotein, for example, imipramine and alprenolol. Neutral and unionized drugs bind to lipoproteins. Lipophilic drugs localize more into adipose tissue.

5. Which drugs easily bind to adipose tissue?
a) Cationic drug
b) Anionic drug
c) Lipophilic drug
d) Neutral drug
Answer: c
Clarification: Anionic or acidic drugs bind to HSA easily. Cationic or basic drugs bind easily to alpha 1 acid glycoprotein. Neutral and unionized drugs bind to lipoproteins. Lipophilic drugs localize more into adipose tissue. Since lipophilic drugs are lipid loving they can easily get deposited on the adipose tissue.

6. Which drug easily bind to AAG?
a) Cationic drug
b) Anionic drug
c) Lipophilic drug
d) Neutral drug
Answer: a
Clarification: Anionic or acidic drugs bind to HSA easily. Cationic or basic drugs having negative charge can bind easily to alpha 1 acid glycoprotein, for example, imipramine and alprenolol. Neutral and unionized drugs bind to lipoproteins. Lipophilic drugs localize more into adipose tissue.

7. The extent of drug-protein binding can change with both changes in protein and drug concentration.
a) True
b) False
Answer: a
Clarification: The concentration of drug that binds to HSA do not have much influence on HA, since any concentration of drug in less than the concentration of HSA. The therapeutic concentration of lidocaine can saturate AAG with which it binds as the concentration of AAG is much less in comparison to that of HSA in blood.

8. In the equation X= Vd C, what does X stands for?
a) Amount of drug in the blood
b) Amount of drug in plasma
c) Amount of drug in the tablet
d) Amount of drug in the body
Answer: d
Clarification: The relationship between tissue-drug binding and apparent volume of distribution can be established as Vd = amount of drug in the body (X)/ Plasma drug concentration (C).

9. Only unbound or free drug is capable of being eliminated.
a) True
b) False
Answer: a
Clarification: Unbound or free drug is capable of being eliminated. Because the drug-protein complex cannot penetrate into the metabolizing organ. The large molecular size of the complex also prevents it from getting filtered through the glomerulus.

10. Penicillin has short plasma half-life although it can bind to plasma protein rigidly.
a) True
b) False
Answer: a
Clarification: Penicillin has a short plasma half-life. Though it can rigidly bind to the plasma still it has short elimination half live. This is because equilibration occurs between the free and the bound protein and the free drug is equally rapidly excreted by active secretion in renal tubules.

11. What kind of graph is shown in the picture?

a) Direct plot
b) Scatchard plot
c) Double reciprocal plot
d) Michele’s menten plot
Answer: a
Clarification: The graph which is got by potting r v/s D then we call it a direct plot. When all the binding sites are occupied by the drug, the protein is saturated and plateau is reached. At the plateau r=N.

12. What kind of graph is shown in the picture?

a) Direct plot
b) Scatchard plot
c) Double reciprocal plot
d) Michele’s menten plot
Answer: b
Clarification: The plot between r/d v/s r is known as Scatchard plot. This plot is a straight line. The slope of the line –Ka, Y intercept is NKa and X intercept is N.

13. What kind of graph is shown in the picture?

a) Direct plot
b) Scatchard plot
c) Double reciprocal plot
d) Michele’s menten plot
Answer: c
Clarification: Double reciprocal plot is also known as Lineweaver Burk plot. This plot of 1/r versus 1/D yields a straight line with slope 1/NKa and Y-intercept 1/N.

14. Displacement interactions are significant in the case of drugs which are more than 95% bound.
a) True
b) False
Answer: a
Clarification: A displacement of 1% and 99% bound drug results in doubling of the free drug concentration i.e. a 100% rise. For a drug which is bound to 99% and a displacement of 1% results in only a 10% rise in freed rug concentration which may be insignificant clinically.

15. Which of the following is a correct method to find the fraction of unbound drug in plasma? Given where Cu is the concentration of unbound drug and C is total plasma drug concentration.
a) CuC
b) C / Cu
c) Cu/C
d) 1/C Cu
Answer: c
Clarification: The fraction of unbound drug can be calculated with the formula fu = Cu/C, where Cu is the concentration of unbound drug and C is total plasma drug concentration and fu is the unbound drug.

To practice all written questions on Drug Biotechnology,

Drug Biotechnology Multiple Choice Questions on “Bioavailability – Measurement”.

1. What is bioavailability?
a) The time of absorption of the drug from its dosage form
b) The rate of absorption of the unchanged drug from its dosage form
c) The time of absorption of the unchanged drug from its dosage form
d) The rate of absorption of the drug from its dosage form
Answer: b
Clarification: Physiologic availability, biologic availability or just bioavailability is defined as the rate or the amount of absorption of an unchanged drug from its dosage form. The rate with which the drug is getting absorbed is important since in some treatment such as asthma attack rapid onset action is required.

2. What is the equation of bioavailable fraction?
a) 1/Bioavailable dose
b) 1/Administered dose
c) Bioavailable dose/Administered dose
d) Administered dose/Bioavailable dose
Answer: c
Clarification: The amount of drug that reaches the systemic circulation is known as systemic bioavailability. The bioavailable fraction F refers to the fraction of administered dose that enters the systemic circulation after drug administration. The equation is F = Bioavailable dose/Administered dose.

3. Which of the following is not an objective of bioavailability studies?
a) Primary stages of development of suitable dosage form for new drug
b) Determination of the influence of excipients, patient-related factors, etc
c) Development of new formulations of the existing drugs
d) Control the quantity of the drug to be administered
Answer: d
Clarification: More than the quantity, bioavailability studies are more used to study the quality of a drug product during the early stages of marketing so that the influence of processing factors, storage, and stability on drug absorption can be determined. Other objectives are the development of suitable dosage form, determination of the influence of excipients, patient-related factors, etc. and development of new formulations of the existing drugs.

4. Single-dose bioavailability studies are simple and common.
a) True
b) False
Answer: a
Clarification: Single-dose bioavailability studies are common, easy, offer less exposure to drugs and are less tedious. Although it is difficult in a single dose bioavailability study to predict the steady-state characteristics of a drug and inter-subject variability. Multiple dose study is difficult to control.

5. Multiple dose study is better since we can understand the peak, valley, drug blood levels, etc.
a) True
b) False
Answer: a
Clarification: Multiple dose study is difficult to control since it exposes the subject to a higher level of drug which is dangerous sometimes. This method is very tedious and time-consuming. The advantages of such method are accurately reflected how the drug should be used, easy to predict peak and valley of a drug, can be ethically performed on the patient, better evaluation of the performance of controlled release formulation is possible.

6. Which of the following is the pharmacodynamics method of studying bioavailability?
a) Acute pharmacologic response
b) Plasma-level time studies
c) Urinary excretion studies
d) Stool excretion studies
Answer: a
Clarification: Pharmacodynamic methods are a direct measurement of the drug effect on physiological processes as a function of time. The methods are acute pharmacologic response and therapeutic response. Pharmacokinetics method is indirect methods and these are Plasma level time studies and Urinary excretion studies.

7. Which of the following is not an important parameter of plasma level time studies?
a) Cmax
b) Tax
c) The area under the plasma level-time curve
d) Steady state level
Answer: d
Clarification: Cmax is the peak plasma concentration which shows whether the drug is being absorbed systemically so that it can be able to provide a therapeutic response. Tmax is the peak time which will give the indication of the rate of absorption. The area under the plasma level-time curve gives the measure of the quantity of absorption of the drug that reaches the systemic circulation.

8. What is the equation for bioavailability?
a) [AUC]std Dstd τtest / [AUC]test Dtest τstd
b) [AUC]test Dtest τstd / [AUC]std Dstd τtest
c) [AUC]test Dstd τtest / [AUC]std Dtest τstd
d) 1 / [AUC]std Dtest τstd
Answer: c
Clarification: The equation of bioavailability is [AUC]test Dstd τtest / [AUC]std Dtest τstd, D stands for dose administered, test and std indicate the test and standard doses of the same drug to determine the relative availability. The dosing interval is τ.

9. The urinary excretion of the unchanged drug is directly proportional to the plasma concentration of a drug.
a) True
b) False
Answer: a
Clarification: Urinary excretion studies help in assessing bioavailability is based on the principle that urinary excretion of unchanged drug is directly proportional to the plasma concentration of a drug. If a drug is excreted at least 10 to 20% in the urine, bioavailability can be determined.

10. Which of the following will not be a parameter that should be examined for urinary excretion data?
a) (dX_u/dt)_max
b) (t_u)_max
c) X_u
d) C_max
Answer: d
Clarification: (dX_u/dt)_max is the maximum urinary excretion rate. It is analogous to C_max from plasma level studies since the rate of appearance of drug in the urine is proportional to its concentration in circulation. Its value increases as the rate of absorption increases. (t_u)_max is the time for maximum excretion rate, its value decreases as the absorption rate increases. X_u is the cumulative amount of drug excreted in the urine.

11. Find out the correct option for the marked place in the given picture of the rate of excretion versus midpoint time of urine collection period curve.

a) (dX_u/dt)_max
b) (t_u)_max
c) X_u
d) C_max
Answer: a
Clarification: (dX_u/dt)_max is the maximum urinary excretion rate. This is obtained from the peak of the rate of excretion versus midpoint time of urine collection period. It is analogous to Cmax from plasma level studies since the rate of appearance of drug in the urine is proportional to its concentration in circulation. Its value increases as the rate of absorption increases. (t_u)_max is the time for maximum excretion rate, its value decreases as the absorption rate increases. X_u is the cumulative amount of drug excreted in the urine.

12. Find out the correct option for the marked place in the given picture of the rate of excretion versus midpoint time of urine collection period curve.

a) (dX_u/dt)_max
b) (t_u)_max
c) X_u
d) C_max
Answer: b
Clarification: (dX_u/dt)_max is the maximum urinary excretion rate. This is obtained from the peak of the rate of excretion versus midpoint time of urine collection period. (t_u)_max is the time for maximum excretion rate, its value decreases as the absorption rate increases. The curve is analogous to plasma-level time profile obtained after oral administration of a single dose of the drug.

13. Which of the following is not measured in acute pharmacological response study?
a) ECG
b) EEG
c) Pupil diameter
d) Serum drug level
Answer: d
Clarification: When bioavailability measurement using pharmacokinetic processes are difficult, inaccurate, non-reproducible, acute pharmacological effect such as a change in ECG, EEG, pupil diameter, etc. is related to the time course of a given drug. Bioavailability can then be calculated by construction the pharmacologic effect-time curve as well as dose-response graphs.

14. Therapeutic response is based on observing the clinical response to a drug formulation.
a) True
b) False
Answer: a
Clarification: Therapeutic response is based upon the clinical responses to a drug formulation given to patients suffering from the disease for which the drug should be used. A drawback of the method is the quantification of observed response is not proper to allow for assessment of relative bioavailability between dosage forms of the same drug.

15. In vitro determination of bioavailability by dissolution rate is not the best way to determine therapeutic efficacy.
a) True
b) False
Answer: b
Clarification: Physicochemical property of most of the drugs that have the greatest influence on their absorption characteristics from the gastrointestinal tract is dissolution rate. To assess the therapeutic efficacy of slow dissolving drugs is in vivo determination of bioavailability. It is done whenever a new formulation is to be introduced in the market.

Drug Biotechnology test on “Controlled Release Medication – Food and Drug Administration in India”.

1. What is the other name of the food and drug act?
a) Wiley Act
b) Wily act
c) Will Act
d) Wheel Act
Answer: a
Clarification: In June 1906, President Theodore Roosevelt signed the Food and Drug Act which is also known as the “Wiley Act”. Under these acts, all the medical equipment, drugs, foods, food colorants, preservatives, spices, nutraceuticals, pharmacy compounds everything has proper guidelines which should be followed by the manufacturer, retailer, storage, etc.

2. What is the full form of the FDA?
a) Federal Agency
b) Food and Drug Administration
c) Food and Drug Agency
d) Food Drug Alliances
Answer: b
Clarification: Food and Drug Administration or FDA is under the agency of the United States Department of Health and Human Services. FDA gives permission for the marketing of all the medical equipment, drugs, foods, food colorants, preservatives, spices, neutraceuticals, pharmacy compounds, and everything has proper guidelines which should be followed by the manufacturer, retailer, storage, etc.

3. For which of the following FDA is not at all responsible?
a) Foods
b) Radiation-emitting devices
c) Cosmetics
d) Vehicles
Answer: d
Clarification: FDA is responsible for the safety regulation of foods, dietary supplements, drugs, vaccines, biological medical products, blood products, medical devices, radiation-emitting products, veterinary products, and cosmetics. FDA is not at all responsible for the manufacturing of vehicles.

4. FDA regulates aspects of prescription drugs.
a) True
b) False
Answer: a
Clarification: FDA monitors potential risks of the product, regulate aspects of prescription drugs such as testing, manufacturing, labeling, advertising, marketing, efficacy, and safety. FDA also evaluates marketing applications in a timely fashion. Facilities inspections by FDA are common.

5. What do the Pediatric Rule states?
a) No drug should be tested on children
b) No separate drug for children
c) Include usage of pediatric use of a product
d) Advertise the pediatric usage
Answer: c
Clarification: Under the Pediatric Rule introduced in 1998, companies introducing new active ingredients for biologics and drugs, and new dosage forms or indications for existing biologics and drugs, are supposed to assess the effects of the drugs in children and include information about pediatric use of the product in their post-marketing reports.

6. What is meant by Fast Track provision?
a) Send medicines fast
b) Common medicines should reach poor people
c) Rapid approval of priority medications
d) Rapid selling of priority medications
Answer: c
Clarification: Under the Food and Drug Modernization Act of 1997 which is also known as the Fast track provisions, the FDA tries to rapidly approve “priority” medications intended for serious illnesses and for which no alternative currently is available. Such as medicines for Alzheimer, cancers, AIDS, Viral infection may get a speedy approval from the FDA and thus can be available in the market as soon as they are approved.

7. What is the full form of GMP?
a) Good manufacturing provisions
b) Good Monitoring prohibitions
c) Good medical practices
d) Good manufacturing practice
Answer: d
Clarification: According to the rules of FDA good manufacturing practice regulations to which the companies must conform in their manufacturing. Products which will not be manufactured in accordance with good manufacturing practice regulations may be adulterated or misbranded and subject to seizure and in the worst cases, these companies can be told to shut down. All the medicines, cosmetics, etc. have different manufacturing guidance which each and every industry is intended to listen to.

8. What is meant by the Good Manufacturing Practice Regulations?
a) Followed by manufacturing companies
b) Only followed by MNCs
c) Followed in the labs only
d) Followed only for cosmetics
Answer: a
Clarification: According to the rules of FDA good manufacturing practice regulations to which the companies must conform in their manufacturing. All the drugs, medical equipment, injections, cosmetics, etc, have different manufacturing guidelines according to FDA which should be followed by manufacturing units. Products which will not be manufactured in accordance with good manufacturing practice regulations may be adulterated or misbranded and subject to seizure and in the worst cases, these companies can be told to shut down.

9. What are generic drugs?
a) Drugs for poor people
b) Patented products can be manufactured by other companies once the patent is lost
c) These drugs do not need FDA approval
d) These drugs don’t have specific guidelines
Answer: b
Clarification: When new drugs are introduced, they are patented by brand-name drug companies. When these patents get expire, other companies can make drugs using the same active ingredient. These drugs are known as generic drugs. Generic drug companies must submit an abbreviated new drug application demonstrating that their products are bioequivalent to a drug product already on the market. Generic drugs are sold at much lower prices than the original one.

10. What is the full form of OTC?
a) Over the counter
b) Once Treated
c) Over the century
d) Over the country
Answer: a
Clarification: OTC drugs are available to consumers without a prescription. Drugs are classified as OTC based on their safety profile, the degree to which their benefits outweigh risks. Such as pantoprazole, paracetamol, etc. These drugs are OTC drugs and are available without a prescription.

11. What is meant by OTC drugs?
a) Drugs which are easy to manufacture
b) Drugs which are available without a prescription
c) These drugs do not need FDA approval
d) These drugs don’t have specific guidelines
Answer: b
Clarification: Drugs such as paracetamol, pantoprazole, etc are available without a prescription such drugs are known as Over the counter drugs. OTC drugs are available to consumers without a prescription. Drugs are classified as OTC based on their safety profile, the degree to which their benefits outweigh risks.

12. Which of the following devices are included in Class I devices?
a) Bandages
b) Thermometers
c) Pacemakers
d) Micro ovens
Answer: a
Clarification: FDA has different classes of devices such as Class I includes bandages, gloves, Stethoscopes. Class II devices include thermometers and endoscopes. Class III devices include those which come in contact with the body fluids such as that of pacemakers and heart valves.

13. Which of the following devices are included in Class II devices?
a) Bandages
b) Thermometers
c) Pacemakers
d) Micro ovens
Answer: b
Clarification: FDA has different classes of devices such as Class I includes bandages, gloves, Stethoscopes. These have different kind of manufacturing guidelines and practices which should be followed. Class II devices include thermometers and endoscopes which come in contact with the body fluids. Class III devices include those which come in contact with the body fluids such as that of pacemakers and heart valves.

14. Which of the following devices are included in Class III devices?
a) Bandages
b) Thermometers
c) Pacemakers
d) Micro ovens
Answer: c
Clarification: FDA has different classes of devices. These have different kind of manufacturing guidelines and practices which should be followed. Such as Class I includes bandages, gloves, Stethoscopes. Class II devices include thermometers and endoscopes. Class III devices include those which come in contact with the body fluids and are kept at that place for a long time such as that of pacemakers and heart valves.

15. Which of the following is not included in Radiological products?
a) Stethoscope
b) X rays
c) Microwave ovens
d) Ultrasound
Answer: a
Clarification: Radiological products such as lasers, x-rays and ultrasound machines also may be medical devices are subjected to FDA regulations. Television receivers, microwave ovens, and laser range finding devices, as “radiation-emitting electronic products,” also are subject to FDA regulation. These devices are subject to varying levels of reporting and record-keeping requirements. The radiation-emitting levels are checked by the FDA and are kept under a controllable range.

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Drug Biotechnology Interview Questions and Answers on “Drug Absorption – Influencing Factors and Bioavailability”.

1. Which one of these is a physicochemical property of Drug substance?
a) Drug solubility
b) Disintegration time
c) Age of patient
d) Dissolution time
Answer: a
Clarification: Pharmaceutical factors include factors relating to the physicochemical properties of the drug and dosage. The physicochemical property includes drug solubility, dissolution rate, particle size, etc.

2. Which one of these does not come under a physicochemical property of drugs?
a) Drug solubility
b) Disintegration time
c) Dissolution rate
d) Drug stability
Answer: b
Clarification: Physicochemical properties of drug substances include drug solubility, dissolution rate, particle size, effective surface area, polymorphism, etc. Dissolution time comes under Dosage form characteristics and pharmaceutic ingredients.

3. In the sequence of events in the drug absorption from orally administered solid dosage, which one comes at first?
a) Disintegration
b) Disaggregation
c) Dissolution
d) Absorption
Answer: a
Clarification: The solid dosage form at first disintegrate into smaller granules or aggregates. Those are then deaggregated to form fine particles. In dissolution, the drug is in the solution form and then it gets absorbed.

4. Which one is the correct sequence for drug absorption through the oral route?
a) Absorption – Dissolution – Disintegration – Deaggregation
b) Disintegration – Dissolution – Deaggregation – Absorption
c) Disintegration – Deaggregation – Dissolution – Absorption
d) Disintegration – Deaggregation – Absorption – Dissolution
Answer: c
Clarification: Disintegration of the drug and then Deaggregation and subsequent release of a drug. Followed by the dissolution of the drug in aqueous fluids at the absorption site and the movement of the dissolved drug through the gastrointestinal membrane into the systemic circulation.

5. Patient-related factors of drug absorption do not deal with which one of these?
a) Age
b) Gastric Emptying time
c) Intestinal transit time
d) Pharmaceutic ingredients
Answer: d
Clarification: Patient-related factors include factors related to anatomy, physiology, and pathologic characteristic of a patient. This includes age, Gastric Emptying time, Intestinal transit time, gastrointestinal pH, Disease states, Blood flow, etc.

6. The rate at which drug reaches the systemic circulation is determined by the slowest of the various steps involved in the sequence. This is known as ____________
a) Disintegration time
b) Dissolution time
c) Rate limiting step
d) Gastric Emptying time
Answer: c
Clarification: The rate at which drug reaches the systemic circulation is determined by the slowest of the various steps involved in the sequence. Such a step is known as the rate-limiting. Disintegration time is the time required for the drug to be broken down into smaller particles or aggregates. Dissolution time is the time required for all the drug disintegrated particle to dissolve in the fluid. Gastric emptying time is the emptying time of the stomach.

7. Diffusion coefficient of drug D, Greater the value faster us the dissolution.
a) True
b) False
Answer: a
Clarification: Greater the value faster is the dissolution of the drug into solution. Diffusion decreases as the viscosity of the dissolution medium increase.

8. Greater the surface area lesser is the dissolution.
a) True
b) False
Answer: b
Clarification: Greater the surface area greater is the dissolution. Thus micronization of the drug is preferred. Dissolution can be increased by micronization.