Y1S2 002 III Pharmacology: What the Drug Does to the Body

What is the primary focus of pharmacodynamics?

The study of the mechanisms of action of enzymes and ion channels
The study of how the body affects the drug's chemical structure
The study of how the drug affects the body's physiological functions (correct)
The study of the effects of food on drug absorption

What type of drug action involves the replacement of a deficient substance in the body?

Depression
Replacement (correct)
Stimulation
Irritation

Which of the following is an example of a chemical action of a drug?

Antacids neutralizing stomach acid (correct)
Epinephrine binding to beta receptors
Neostigmine inhibiting acetylcholinesterase
Benzodiazepines depressing the CNS

What is the term for the binding of a drug to a particular target protein in the body?

Mechanism of action (B) Signup and view all the answers

What is the primary mechanism of action of an antagonist?

Binding to receptors without producing a tissue response and preventing an agonist from binding (D) Signup and view all the answers

What type of drug action involves the inhibition of an enzyme's activity?

Enzyme inhibition (D) Signup and view all the answers

What is the product of the affinity of a drug and its intrinsic activity?

Efficacy (B) Signup and view all the answers

What is the term for the study of the effects of drugs on the body?

Pharmacodynamics (B) Signup and view all the answers

What is the definition of a partial agonist?

A drug with high affinity and low intrinsic activity (A) Signup and view all the answers

What is the term for the amount of drug required to produce an effect of a given intensity?

Potency (B) Signup and view all the answers

What is the result of the binding of a drug to a receptor?

Formation of a drug-receptor complex (B) Signup and view all the answers

What is the characteristic of a drug with high affinity but low intrinsic activity?

It is a partial agonist (D) Signup and view all the answers

What is the primary function of channel-linked receptors in the nervous system?

To convert the binding of neurotransmitters into an electrical signal (A) Signup and view all the answers

What is the characteristic structure of G-protein-coupled receptors?

Seven membrane-spanning segments (B) Signup and view all the answers

Which of the following receptors is an example of a channel-linked receptor?

GABAA (A) Signup and view all the answers

What is the effect of the binding of neurotransmitters to channel-linked receptors?

Depolarization of the cell (A) Signup and view all the answers

What is the function of the α subunit in G-protein-coupled receptors?

It possesses GTPase activity (D) Signup and view all the answers

What is the primary difference between channel-linked receptors and G-protein-coupled receptors?

The structure of the receptor (A) Signup and view all the answers

What is the characteristic of a non-competitive antagonist?

It binds to an allosteric binding site and reduces the effect of the agonist (A) Signup and view all the answers

What is the result of competitive antagonism on the dose-response curve?

A shift to the right with no change in slope (D) Signup and view all the answers

What is the primary difference between tachyphylaxis and tolerance?

Tachyphylaxis occurs rapidly, while tolerance develops slowly (D) Signup and view all the answers

What is the mechanism of non-competitive antagonism that leads to a maximal response?

Binding to an allosteric site and reducing the effect of the agonist (A) Signup and view all the answers

What is the result of irreversible antagonism on the receptor?

The receptor is permanently bound and inactivated (B) Signup and view all the answers

What is the mechanism of tachyphylaxis and tolerance that involves changes in the receptor?

Loss of receptors (B) Signup and view all the answers

What is the characteristic of ligands that bind to intracellular nuclear receptors?

Lipophilic compounds (B) Signup and view all the answers

What is the function of the DNA-binding domain of intracellular nuclear receptors?

Recognizing specific base sequences (A) Signup and view all the answers

What is the role of the zinc atom in the zinc fingers of intracellular nuclear receptors?

Knotted together by a cluster of 4 cysteine residues (A) Signup and view all the answers

What is the effect of altered protein synthesis on the physiological response to intracellular nuclear receptors?

Slow onset of action (D) Signup and view all the answers

What is the significance of the variable region upstream of the DNA-binding domain in intracellular nuclear receptors?

Controlling gene transcription (A) Signup and view all the answers

What is the focus of pharmacogenomics in relation to therapeutic drugs?

The genetic influence of an individual on therapeutic drugs (B) Signup and view all the answers