Week 1 MCQ Flashcards
Which ONE of the following receptor types is capable of the fastest response (milliseconds)?
A. kinase-linked receptors B. nuclear receptors C. metabotropic receptors D. ionotropic receptors E. G-protein coupled receptors
d
In G-protein coupled receptors what is the correct order of events following G-protein activation that leads to a cellular response?
A. second messenger – primary effector – secondary effector –cellular response B. primary effector – secondary effector – second messenger – cellular response C. primary effector – second messenger – secondary effector – cellular response D. secondary effector – second messenger – primary effector –cellular response E. second messenger – secondary effector – primary effector –cellular response
c
Schedule 4 drugs are usually available:
A. only from pharmacists on a prescription B. from a pharmacy, but a pharmacist must be aware of the sale C. in supermarkets D. only with prior authority from the Department of Health E. from a pharmacy
a
f a drug has an apparent volume of distribution of 10 litres and a plasma concentration of 2mg/ml, the total amount of drug in the body is around:
A. 20 mg B. 2 mg C. 20 g D. 200 mg E. 2.0 g
CorrectC.
20 g
You need to give an 80 kg patient a loading dose of drug X by a single intravenous injection, prior to commencing an i.v. infusion. The required plasma concentration of drug X is 0.2 mg/ml. Given that the apparent volume of distribution (Vd) of drug X is 0.5 litres/kg, what loading dose of drug X will most closely reach this concentration?
A. 8 g B. 40 mg C. 8 mg D. 160 g E. 16 mg
a
A patient is started on an infusion of an antibiotic drug at a constant rate. The antibiotic has a half-life of 1 hours. How long will it take for the antibiotic to reach a steady-state level in the blood?
A. it depends on the infusion rate B. 2-3 hours C. 4-5 hours D. 3-4 hours E. 1-2 hours
C.
4-5 hours
ntagonists for a specific receptor possess:
A. Affinity and efficacy B. Affinity and intrinsic activity C. Affinity only D. Efficacy only E. Intrinsic activity only
c
Which of the following statements is FALSE regarding irreversible competitive antagonist?
A. Agonist will act normally at unoccupied receptors B. The Emax is decreased for the agonist C. The ED50 is increased for the agonist D. The antagonist dissociates slowly, or not at all, from the receptors E. No change in antagonist occupancy takes place when the agonist is applied
CorrectC.
The ED50 is increased for the agonist
Amphetamines are weak bases with a pKa of around 9.8. Their elimination from the body can be increased by which one of the following?
A. It is not possible to increase the elimination of weak bases. B. Alkalinisation of the urine using sodium bicarbonate C. Acidification of the urine using sodium bicarbonate D. Alkalinisation of the urine using ammonium chloride E. Acidification of the urine using ammonium chloride
e
Star fruit increases the plasma concentration of statins due to which of the following mechanisms?
A. activation of CYP2D6 B. inhibition of CYP3A4 C. decreased statin secretion in the kidney tubule D. a decrease in gastric pH E. an acceleration in gastric emptying
b
The Therapeutic Goods Administration (TGA) has classified category A drugs in pregnancy as drugs that:
A. have not been fully evaluated in prenant women B. increase the incidence of foetal malformations or irreversible damage C. have been used by many pregnant women and there is no proven increase in the frequency of harmful effects on the foetus D. may cause harmful effects to the foetus without causing malformations E. have a high risk of causing permanent damage to the foetus and should not be used in pregnancy, or when there is a possibility of pregnancy
c
Which ONE of the following is NOT a chronic effect of ethanol abuse?
A. higher glucose metabolism B. brain shrinkage C. loss or damage to neurons and glial cells D. enlarged ventricles visible on a CT/MRI scan of the brain E. irreversible neurological abnormalities
a
A drug has a steady-state plasma concentration of 300 mg/ml and an elimination half-life of 30 minutes. Approximately how long will you have to wait till most (> 95%) of the drug has been lost from the body?
A. 4 - 5 hours B. 1 hour C. 1 - 2 days D. 2 - 2.5 hours E. not enough information is given to calculate this
d
Which of the following is NOT a factor that contributes to individual variation to drugs?
age
interactions with other drugs
genetic factors
liver disease
route of drug administration
E
The amount of plasma protein binding of a drug may affect:
A. the concentration of unbound drug in plasma B. the amount available for metabolism in the liver C. all of the above D. the amount available to bind to its site of action E. the amount available for filtration through the kidneys
c
