BISC 4120 - Exam 1 Quizzes

In this example, drug A would be described as:

- less potent

- less efficacious

- more potent

- more efficacious

more potent

Drugs that block the action of an endogenous hormone are known as:

- antagonists

- agonists

- allosteric modulators

antagonist

Which type of receptor activates signal transduction pathways inside the cell by directly phosphorylating target proteins?

- receptor tyrosine kinase

- ligand-gated ion channel

- G protein-coupled receptor

- nuclear receptor

receptor tyrosine kinase

If a drug is dissolved at a concentration of 1x10^-9M, this could also be expressed as:

- 1 nanomolar (nM)

- 1 micromolar (uM)

- 1 millimolar (mM)

1 nanomolar (nM)

One reason that spare receptors occur is because of:

- receptor internalization

- covalent binding of drugs to receptors

- signal amplification by second messenger pathways

signal amplification by second messenger pathways

If a drug has a low Kd, we can also say that it has a:

-low affinity

-high affinity

high affinity

Which of these is associated with receptor antagonism that is surmountable (can be overcome by adding more agonist)?

- competitive antagonist

- negative allosteric modulators

- noncompetitive antagonist

competitive antagonists

If a drug has a narrow therapeutic index, this means that:

- the drug only works for a small percentage of the population

- the drug is specific to a small number of receptor types in the body

- the difference between its therapeutic dose and toxic dose is small

the difference between its therapeutic dose and a toxic dose is small

Constitutive activity describes a phenomenon where:

- some receptors display a low level of activation even in the absence of an agonist

- a partial agonist can block the effects of a full agonist

- a drug increases receptor activity by binding to an allosteric site on the receptor

some receptors display a low level of activation even in the absence of an agonist

On a quantal dose response curve, the ED50 value tells you:

- the minimum dose that causes adverse effects

- the dose that produces half of the maximum effect

- the dose that is effective in half of the population

the dose that is effective in half of the population

A weak acid drug with pKa of 6.2 is taken orally. In the stomach, it will be:

- approximately 50% ionized

- almost 100% non-ionized

- almost 100% ionized

almost 100% non-ionized

Which answer correctly describes the way that a noncompetitive antagonist will shift the dose-response curve?

- the curve will be shifted to the left while maintaining the same shape

- the curve will be shifted to the right and plateau at less than 100%

- the curve will be shifted to the right while maintaining the same shape

the curve will be shifted to the right and plateau at less than 100%

If a drug has a narrow therapeutic index:

- a high concentration of the drug is needed to achieve a therapeutic effect

- there is not much difference between a therapeutic and toxic dose

- the drug binds to many receptors in a nonspecific manner

there is not much difference between a therapeutic and toxic dose

What type of drug would cause an agonist dose-response curve to shift to the left? (become more sensitive)

- positive allosteric modulator

- negative allosteric modulator

- competitive antagonist

- noncompetitive antagonist

positive allosteric modulator

Inverse agonists are drugs that:

- decrease the constitutive signaling of a receptor

- activate the receptor but do not achieve a 100% effect

- bind to a site on a receptor that is distinct from the active site

decrease the constitutive signaling of a receptor

The term for decreased receptor expression after chronic agonist exposure is:

- upregulation

- downregulaiton

- tachyphylaxis

down regulation

A drug molecule is found to be 100% ionized in the small intestine. It is likely that this drug will be:

- poorly absorbed in the small intestine

- extensively absorbed in the small intestine

poorly absorbed in the small intestine

Which of these properties would increase the distribution of a drug into the brain?

- high molecular weight

- high lipid solubility

- high number of charges on the molecule

high lipid solubility

Phase I metabolic reactions:

- are conjugation reactions that add groups such as glucuronic acid to a drug molecule

- typically involve oxidation, reduction, or hydrolysis

- are always required to occur before phase II reactions

typically involve oxidation, reduction, or hydrolysis

Alcohol enhances acetaminophen toxicity because it:

- induces the P450 pathway that produces NAPQI

- acts as a competitive inhibitor of acetaminophen metabolism

- inhibits the metabolism of acetaminophen

induces the P450 pathway that produces NAPQI

A patient experiences an allergic reaction to penicillin. This is an example of _____ toxicity.

- intrinsic

- idealistic

- idiosyncratic

idiosyncratic

A drug undergoes extensive metabolism in the liver via the first pass effect. This means that it will have:

- low bioavailability

- long half-life

- high volume of distribution

low bioavailability

Compared to extensive metabolizers, patients who are CYP2D6 poor metabolizers will experience _____ analgesia when they take codeine.

- more

- less

less

If a drug has a high volume of distribution, this indicates that:

- a large fraction of the drug dose leaves the plasma and binds to tissue sites

- a large fraction of the drug is metabolized by the lover before reaching the systemic circulation

- a large fraction of the drug is excreted unchanged

- a large fraction of the drug dose stays in the plasma

a large fraction of the drug dose leaves the plasma and binds to tissue sites

In a heart that is beating at normal resting rate of 70 beats per minute, what would be the effect of complete blockade of muscarinic receptors by a muscarinic antagonist drug?

- the heart rate would increase approximately 100 beats per minute

- there would be no effect one eating heart rate

- the heart rate would decrease below the normal resting rate

- the heart rate would increase to the maximum (approximately 180-200 beats per minute)

the heart rate would increase approximately 100 beats per minute

Which of these is NOT a location where nicotinic acetylcholine receptors are typically found?

- sympathetic ganglia

- parasympathetic target organs

- parasympathetic ganglia

- the neuromuscular junction

parasympathetic target organs

Many organs receive dual innervation from both divisions of the autonomic nervous system. An important exception is:

- the heart, which only receives parasympathetic innervation

- the bladder, which only receives parasympathetic innervation

- the lungs, which only receive sympathetic innervation

- the blood vessels, which only receive sympathetic innervation

the blood vessels, which only receive sympathetic innervation

What is the mechanism of action and effect for organophosphates?

- inhibition of acetylcholinesterase leading to a cholinomimetic effect

- antagonism of muscarinic receptors leading to a cholinomimetic effect

- inhibition of acetylcholinesterase leading to a cholinolytic effect

- direct activation of nicotinic receptors leading to a cholinomimetic effect

inhibition of acetylcholinesterase leading to a cholinomimetic effect

The drug bethanechol is:

- an anticholinesterase

- an anticholinergic

- an muscarinic antagonist

- a muscarinic agonist

a muscarinic agonist

Which of these symptoms would NOT typically be seen in a patient who overdosed on an anticholinergic medication?

- profuse sweating

- decreased salivation

- altered mental status

- dilated pupils (mydriasis)

profuse sweating

Botulinum toxin works by:

- blocking muscarinic receptors

- inhibiting neurotransmitter release

- inhibiting acetylcholinesterase

- blocking alpha-1 receptors

inhibiting neurotransmitter release

Reflex tachycardia would most likely to occur with which type of drug?

- vasodilator

- beta blocker

- muscarinic agonist

- vasoconstrictor

vasodilator

Norepinephrine is a relatively poor agonist at which receptor type?

- alpha-2

- beta-2

- beta-1

- alpha-1

beta-2

Which of these drugs activates alpha-2 receptors?

- propranolol

- albuterol

- clonidine

- atropine

clonidine

Which drug class can exacerbate asthma?

- alpha-1 agonists

- nonselective beta blocker

- nonselective alpha blockers

- indirect-acting sympathomimetics

nonselective beta blocker

Which drug class has the highest risk of sympathomimetic toxicity?

- nonselective alpha blockers

- indirect-acting sympathomimetics

- alpha-1 agonists

- nonselective beta agonists

indirect-acting sympathomimetics