Y1S2 002 II Pharmacology: Understanding Drug Effects on the Body

What is the main focus of pharmacodynamics?

The effects of drugs and their mechanisms of action in the body (correct)
The chemical composition of drugs and their interactions
How the body absorbs, distributes, and eliminates drugs
The psychological impact of drugs on the mind

What type of drug action increases heart rate?

Stimulation (correct)
Irritation
Replacement
Depression

What type of target protein do most drugs bind to?

Ion channels
Enzymes
Carriers
Receptors (correct)

What is the mechanism of action of antacids?

Chemical action (C) Signup and view all the answers

What is the role of insulin in diabetes management?

Replacement of a lacking hormone (A) Signup and view all the answers

What is the term for the study of the effects of drugs and their mechanisms of action in the body?

Pharmacodynamics (A) Signup and view all the answers

What is the characteristic of a non-competitive antagonist?

It binds to the receptor and stays bound irreversibly (C) Signup and view all the answers

What is the effect of a competitive antagonist on the dose-response curve of an agonist?

It shifts the curve to the right without a change in slope (D) Signup and view all the answers

What is the mechanism of tachyphylaxis and tolerance due to a change in receptors?

It occurs in receptors coupled to ion-channels and second messengers (C) Signup and view all the answers

What is the difference between tachyphylaxis and tolerance?

Tachyphylaxis is a rapid decrease in responsiveness, while tolerance is a gradual decrease (C) Signup and view all the answers

What is the characteristic of an irreversible antagonist?

It cannot be unbound from the receptor (D) Signup and view all the answers

What is the effect of a non-competitive antagonist on the maximal response of an agonist?

It decreases the maximal response (C) Signup and view all the answers

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

They are lipophilic compounds (D) Signup and view all the answers

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

To recognize specific base sequences (C) Signup and view all the answers

What is the effect of altered protein synthesis on the physiological response?

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

What is the structure of the DNA-binding domain in intracellular/nuclear receptors?

Two loops of about 15 residues each (C) Signup and view all the answers

What is the role of the variable region in intracellular/nuclear receptors?

To control gene transcription (C) Signup and view all the answers

What is the study of the genetic influence of an individual on therapeutic drugs?

Pharmacogenomics (B) 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 (B) Signup and view all the answers

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

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

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

Possessing GTPase activity (B) Signup and view all the answers

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

Direct vs. indirect coupling to ion channels (B) Signup and view all the answers

What is the result of the depolarization of the cell membrane through channel-linked receptors?

Generation of a action potential (A) Signup and view all the answers

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

nACh (C) Signup and view all the answers

What is the result of phosphorylation of regions of the receptor?

Down regulation of the receptor (D) Signup and view all the answers

Which of the following is a mechanism of physiological adaptation?

Homeostatic responses that nullify the drug's effect (B) Signup and view all the answers

What is the purpose of the Therapeutic Index (TI)?

To quantify the safety of a drug (C) Signup and view all the answers

What is the main difference between the four types of receptors?

Their molecular structure, coupling and effector (C) Signup and view all the answers

What is the effect of repeated administration of a drug at the same dose?

Progressive lowering of the plasma concentration of the drug (A) Signup and view all the answers

What is the term for the dose at which 50 percent of the population or sample manifests a given toxic effect?

Median Toxic Dose (TD50) (B) Signup and view all the answers