Pharmacology
???????? Topic : Pharmacokinetics : AD????????
1️⃣ The rate of drug transport across a cell membrane by lipid diffusion depends on all of the following EXCEPT:
A. Drug size (diffusion constant)
B. Surface area of absorption
C. Lipid partition coefficient
D. Density of transporters
2️⃣ The major mechanism of drug transport involved in the transport of drug out of the blood into tissues is:
A. Aqueous diffusion
B. Lipid diffusion
C. Active transport
D. Facilitated transport
3️⃣ The distribution of drugs into the central nervous system (brain) usually depends on:
A. Aqueous diffusion
B. Lipid diffusion
C. Active transport
D. Facilitated transport
4️⃣ Following intravenous administration, drugs are distributed fastest to:
A. the skin, kidney, and brain
B. the liver, kidney, and brain
C. the liver, adipose, and brain
D. the liver, kidney, and adipose
5️⃣ Which of the following characteristics is most likely to be associated with a high apparent volume of distribution?
A. Penetration across the blood:brain and blood:testes barriers
B. Extensive binding to plasma protein
C. Distribution into total body water
D. Extensive binding to tissue constituents
6️⃣ The volume of distribution of drugs is __
A. An expression of total body volume
B. A measure of total fluid volume
C. A relationship between the total amount of drug in the body and the concentration of the drug in the blood
D.Proportional to bioavailability of the drug
7️⃣ The loading dose of a drug is based upon the:
A. Time taken for complete elimination
B. Percentage of drug excreted unchanged in urine
C. Percentage of drug bound to plasma protein
D. Apparent volume of distribution and the desired drug concentration in plasma
8️⃣ If a drug has a very small volume of distribution(Vd ), it is likely that this drug (GATE 1998)
A.Has a short biological life
B. Does not accumulate in various tissues and organs
C. Not bioavailable
D.Will not be effective
9️⃣ The initial distribution of a drug into the tissue is determined chiefly by__
A. Rate of blood flow to the tissue
B.Plasma protein binding of the drug
C.Affinity for the tissue
D.Stomach emptying time
???? The ultra short-acting barbiturates have brief duration of action due to__
A. High degree of binding to plasma protein
B.Low lipid solubility resulting in a minimal concentration in the brain
C.Metabolism is slow in the liver
D.Rapid rate of redistribution from the brain due to its high liposolubility
Answers
1. D ( Density of transporters )
2. A ( Aqueous diffusion )
3. B ( Lipid diffusion )
4. B ( Liver , Kidney , Brain )
5. D ( Extensive binding to tissue constituents)
6. C ( A relationship between total amount of drug in the body & concentration of drug in the blood )
7. D ( Apparent volume of distribution and the desired drug concentration in plasma )
8. B ( Does not accumulate in various tissue and organs )
9. A ( Rate of blood flow to tissue )
10. D ( Rapid rate of redistribution from the brain due to its high liposolubility )