Biopharmaceutics & Pharmacokinetics (BP604TT)
Chapter 1 ABSORPTION
51. Absorption of griseofulvin is……………
- (a) Dissolution rate limited
- (b) Permeation rate limited
- (c) Perfusion rate limited
- (d) None of the above
Answer: a
52. Micronized form of drug absorbed fast because
- (a) surface area increased
- (b) viscosity increased
- (c) angle of distribution increased
- (d) none of the above
Answer: a
53. …………form of weakly acidic drug absorbed well in stomach
- (a) ionized
- (b) unionised
- (c) both
- (d) none of the above
Answer: b
54. According to pH partition theory, a weak acidic drug will most likely be absorbed from the stomach because the drug which exist primarily in the
(a) Unionized, more lipid soluble form
(b) Ionised, more water soluble form
(c) Form of weak acid and more soluble in acid media
(d) Ionic form of the drug, which facilitates diffusion
Answer: a
55. Very weak bases having pKa < 5
(a) Are ionized in the entire pH range of GIT
(b) Show absorption, which is pH dependent
(c) Are unionized at all pH values
(d) None of the above
Answer: c
56. Micronized form of drug absorbed fast because
(a) Surface area increased (b) Viscosity increased
(c) Angle of distribution increased (d) none of the above
Answer: a
57. IV route of drug administration does not involve…………
- (a) distribution step
- (b) absorption stec
- (c) biotransformation step
- (d) All of the above
Answer: b
58. In carrier mediated transport energy is derived from……..
(a) Hydrolysis of ATP
(b) Protein metabolism
(c) Concentration gradient
(d) All of the above
Answer: a
59. Which of the following drug is not stable in the gastric fluid?
- (a) Erythromycin
- (b) Paracetamol
- (c) Salicylic acid
- (d) none of the above
Answer: a
60. ………types of drugs are absorbed by pore transport mechanism.
(a) Macromolecules
(b) Ionic drugs
(c) Drugs with molecular weight 100-400
(d) Water soluble drugs of molecular weight less than 100
Answer: d
61. Area in which the carrier system is most dense is called as…………..
- (a) Therapeutic window
- (b) Absorption index
- (c) Therapeutic index
- (d) Absorption window
Answer: d
63. ………..is known as nonionic diffusion
- (a) Passive diffusion
- (b) Ion-Pair transport
- (c) Pore transport
- (d) Endocytosis
Answer: a
63. Which of the following is carrier mediated transport system
- (a) passive diffusion
- (b) active transport
- (c) pore transport
- (d) none of the above
Answer: b
64. Absorption of poorly soluble drug is
- (a) diffusion rate limited
- (b) dissolution rate limited
- (c) both (a) & (b)
- (d) none of the above
Answer: b
65. Which of the following process drug moves from site of administration to systemic circulation?
(a) excretion
(b) absorption
(c) distribution
(d) metabolism
Answer: b
66. Based on Henderson-Hasselbalch equation, at what pH value a weak acid would be 99.9% ionized?
- (a) At pH equivalent to pKa – 3
- (b) At pH equivalent to pKa + 3
- (c) At pH equivalent to pKa – 1
- (d) At pH equivalent to pKa + 1
Answer: b
67. In passive diffusion, the transport of drugs takes place from a region of ……………concentration to a ……………..concentration.
- (a) Lower, Higher
- (b) Higher, Lower
- (c) Both (a) and (b)
- (d) none of the above
Answer: b
68. 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
69. 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
70. 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
71. What is the driving force of Pore Transport?
a) Hydrostatic pressure
b) Concertation Gradient
c) Electrochemical gradient
d) Charge equilibration
Answer: a
72. 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
73. 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
74. 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
75. 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
76. 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
77. 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
78. Which of these absorption methods involves engulfing of the extracellular drug?
a) Endocytosis
b) Passive diffusion
c) Facilitated diffusion
d) Ion-Pair transport
Answer: b
79. Which is the other name of “cell eating”?
a) Transcytosis
b) Phagocytosis
c) Pinocytosis
d) Endocytosis
Answer: b
80. Transfer of an endocytic vesicle from one extracellular compartment to another is known as
a) Phagocytosis
b) Transcytosis
c) Pinocytosis
d) Endocytosis
Answer: b
81. A drug can be absorbed by more than one mechanism.
a) True
b) False
Answer: a
.
82. Which kind of absorption mechanism is showing in the picture?
a) Endocytosis
b) Passive transport
c) Active transport
d) Facilitated diffusion
Answer: b
83. 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
84. 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
85. 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
86. 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
87. 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
88. 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 timd
b) Dissolution time
c) Rate limiting step
d) Gastric Emptying time
Answer: c
89. Diffusion coefficient of drug D, Greater the value faster us the dissolution.
a) True
b) False
Answer: a
90. Greater the surface area lesser is the dissolution.
a) True
b) False
Answer: b
91. Which one of the following is a critical rate-limiting step of drug absorption?
a) Rate of drug disintegration
b) Size of the drug
c) Size of the porous particle
d) Rate of dissolution
Answer: d
92. Which sentence will define the Dissolution rate?
a) Amount of solid substrate that goes into solution under constant time
b) Amount of solid substrate that goes into solution under constant time under standard temperature
c) Amount of solid substrate that goes into solution under constant time under standard temperature, pH, and pressure
d) Amount of solid substrate that goes into solution under constant time under standard temperature, pH, solvent composition and constant surface area
Answer: d
93. What should be the ideal solubility rate of an orally administered drug in the pH range of 2 to 8?
a) 3-4mg/ml
b) 4-6 mg/md
c) 7-8 mg/ml
d) 1-2 mg/ml
Answer: d
94. Which one of these is not a theory of Drug dissolution?
a) Diffusion layer model
b) Fick’s law of diffusion
c) Penetration or surface renewal theory
d) Interfacial barrier model
Answer: b
95. Which theory takes into account that a thin film is created by the solution of the solid at the solid- liquid interface?
a) Interfacial barrier model
b) Diffusion layer model
c) Penetration or surface renewal theory
d) Danckwert’s model
Answer: b
96) In the equation G=Ki (Cs-Cb), what does G stands for______________
a) Dissolution rate per unit area
b) Effective interfacial transport constant
c) Concentration of the solute
d) Concentration of the impurity
Answer: a
97. Which model does not approve the existence of the stagnant layer in the solid-liquid interface?
a) Interfacial barrier model
b) Diffusion layer model
c) Penetration or surface renewal theory
d) Danckwert’s model
Answer: a
98. What does the interfacial barrier model states?
a) An intermediate concentration exists at the interface
b) Turbulence in the dissolution medium exists at the solid/liquid interface
c) Formation a thin film or layer at the solid-liquid interface
d) Solutes passes easily through the interfaces
Answer: a
99. In the equation, Wo1/3-W1/3=Kt, K stands for ____________
a) The original mass of the drug
b) Mass of the drug remaining after time t
c) Dissolution constant
d) Concentration of solute
Answer: c
100. Which are the two rate-determining step of drug absorption when given orally?
a) Disintegration and deaggregation
b) Disintegration and Dissolution
c) Dissolution and permeation through the membrane
d) Permeation through the membrane and Disintegration
Answer: c
