Formative quizzes Flashcards
Which of the following statements is TRUE concerning agonists?
a. An agonist is an agent that by binding to a receptor initiates a cellular response b. All receptors are inactive unless an agonist is bound c. An agonists that inhibits a cellular function has an efficacy less than zero d. All agonists bind to the extracellular portion of their respective receptors
An agonist is an agent that by binding to a receptor initiates a cellular response
Which of the following statements below are FALSE?
a. Proteins that function as drug targets generally show a high degree of ligand specificity b. The great majority of drugs act with complete specificity c. A small change in a molecule, eg. alteration in chirality, can inactivate the molecule d. A useful drug must act selectively on particular cells and tissues
The great majority of drugs act with complete specificity
The total number of agonist binding sites in a preparation can be determined from which of the following?
a. concentration-response curve b. scatchard plot c. schild plot d. Using the Hill Equation
scatchard plot
Four agonists (A, B, C & D) all contract the guinea-pig ileum preparation by acting upon muscarinic receptors. The concentration-response curves for each agonist is shown in the graph below.
Which of the statements is TRUE
a. When given together, the response to a given concentration of A and B will be greater than that of either given alone b. When given together, the response to a given concentration of A and B will be less than that of either given alone c. When given together, the response to a maximum concentration of B and C will be greater than that of either given alone d. When given together, the response to a sub-maximum concentration of B and C will be less than that of either given alone
When given together, the response to a given concentration of A and B will be less than that of either given alone
Which is TRUE about a pro-drug?
a. it is a more ‘active’ form of a drug b. it is a drug that binds particularly well to proteins found in the plasma c. it is a drug that needs to undergo metabolism to form an active drug d. none of the above
c.
it is a drug that needs to undergo metabolism to form an active drug
Which of the following statements about the administration and absorption of a drug are true
a. All weak acids, given orally are rapidly absorbed in the stomach b. Strong bases, given orally, are well absorbed in the small intestine c. Sublingual administration of a drug avoids first-pass metabolism d. Drugs are only given orally if they are intended to be absorbed from the gastrointestinal tract
Sublingual administration of a drug avoids first-pass metabolism
Which of the following is TRUE regarding the effect of pH on the urinary excretion of drugs
a. urinary alkalinization has no effect on the excretion of weak bases b. urinary alkalinization accelerates excretion of weak acids c. urinary acidification accelerates excretion of weak acids d. urinary acidification accelerates excretion of weak acids and bases
urinary alkalinization accelerates excretion of weak acids
Which of the following statements is FALSE about the clinical useful effects of NSAIDs?
a. They reduce body temperature b. They reduce pain of musculoskeletal origin c. They eliminate local inflammation d. They decrease oedema
They eliminate local inflammation
The most common adverse effect of most NSAIDs is:
a. thrombosis b. skin rash c. gastrointestinal distress d. renal impairment
GI distress
Which of the following is TRUE about DMARDs
a. like NSAIDs they only reduce the symptoms of disease b. they are used in the treatment of rheumatoid arthritis c. they are antagonists of glucocorticoid receptors d. are commonly used to suppress rejection of transplanted organs
b.
they are used in the treatment of rheumatoid arthritis
Which of the following statements is true of the mechanism of action of benzodiazepine agonists?
they bind to the GABA site on postsynaptic GABA receptors
they act as agonists on presynaptic GABA receptors
the act on postsynaptic GABA receptors causing chloride channels to open
They augment the action of GABA by increasing the number of chloride channels opened by a given concentration of GABA.
They augment the action of GABA by increasing the number of chloride channels opened by a given concentration of GABA.
Which of the following statements is incorrect about epilepsy?
Grand mal: tonic/clonic seizures with loss of consciousness
Petit mal: absence seizures , not associated with convulsions
Partial seizures involving the hypothalamus are associated with loss of consciousness
A seizure may be triggered by fatigue
Partial seizures involving the hypothalamus are associated with loss of consciousness
Which of the following statements is NOT true about tricyclic antidepressants?
haloperidol is a classic example
they can cause urinary retention
they can cause sedation
they inhibit both noradrenaline and 5HT uptake
haloperidol is a classic example
Which of the following is TRUE about diazepam?
it is an agonist at GABAA receptors
it is an inverse agonist at GABAA receptors
it is an allosteric regulator of GABAA receptors
it is an antagonist at GABAB receptors
it is an allosteric regulator of GABAA receptors
Which of the following is FALSE about GABAA receptors?
A. they are therapeutic target of anxiolytics B. they are a therapeutic target of anti-convulsants C. they couple to Gi proteins to inhibit the activity of adenylate cyclase D. overdose of agonists at these receptors can be lethal
they couple to Gi proteins to inhibit the activity of adenylate cyclase
