Definitions

Question 1

Concentration effect

Answer 1

Phenomenon by which the rise in alveolar partial pressure of nitrous oxide is disproportionately rapid when administered in high concentrations

Question 2

Second gas effect

Answer 2

The phenomenon by which the speed of onset of inhalational anaesthetic agents is increased when administered with nitrous as a carrier gas.

Question 3

Isomerism

Answer 3

The phenomenon where molecules with the same atomic formulae have different structiral arrangements

Question 4

Structural isomerism

Answer 4

Identical chemical formulae with different order of atomic bonds

Question 5

Tautomerism

Answer 5

Dynamic change between two different forms of a molecular structure depending on environmental conditions

Question 6

Stereoisomerism

Answer 6

Identical chemical formulae and bond structure, with different 3d configuration

Question 7

Enantiomers

Answer 7

Compounds with a single chiral centre that form non super-imposable mirror images of one another

Question 8

Disteroisomers

Answer 8

Compounds with more than one chiral centre subject to geometric isomerism

Question 9

Geometric isomerism

Answer 9

Two dissimilar groups linked by a double bond or ring, created due to the reduced mobility of that bond/ring

Question 10

Chiral centre

Answer 10

central atom bound to four dissimilar groups

Question 11

Enzyme

Answer 11

biological catalyst that increases the speed of a chemical reaction without being consumed by the reaction itself

Question 12

First order reaction

Answer 12

Rate depends upon the concentration of the reacting components- exponential

Question 13

Zero order reaction

Answer 13

A reaction independent of the concentration of reacting components and is therefore constant

Question 14

Summation

Answer 14

Actions of two drugs are additive, each has an independent action

Question 15

Potentiation

Answer 15

The action of one drug is amplified by another, which has no independent action of its own

Question 16

Synergism

Answer 16

Combined action of two drugs is greater than would be expected from a purely additive effect

Question 17

Adverse drug reaction

Answer 17

Occurance of any drug effect not of therapeutic, diagnostic or prophylactic benefit to the patient

Question 18

Anaphylactic reaction

Answer 18

The response to a substance to which an individual has been previously sensitised by the formation of a specific IGE AB. It is characterised by the release of vasoactive substances and the presence of systemic symptoms (ABC)

Question 19

Anaphylactoid reaction

Answer 19

A response to a substance not mediated by a specifiv IGE ab but characterised by the same release of vasoactive substances and presence of systemic symptoms

Question 20

Ligand

Answer 20

Chemical messenger able to bind to a recepto

Question 21

Receptor

Answer 21

Component of a cell that interacts selectively with a compound to initiate biochemical change or cascade to produce the effects of the compound

Question 22

Kd

Answer 22

Molar concentration of a drug at which 50% of its receptors are occupied at equilibrium

Question 23

Affinity

Answer 23

How avidly a drug binds to a receptor

Question 24

Efficacy (IA)

Answer 24

A measure of the magnitude of the effect once a drug is bound

Question 25

Potency

Answer 25

A measure of the quantity of the drug needed to produce maximal effect

Question 26

Median effective concentration

Answer 26

Concentration of a drug that induces a specified response halfway between baseline and maximum

Question 27

Median effective dose

Answer 27

The dose of a drug that induces a specified response in 50% of the population to whom it is administered.

Question 28

Agonist

Answer 28

A drug that binds to a specific receptoy and once bound is able to produce a response

Question 29

Antagonist

Answer 29

A drug with affiniity but no intrinsic activity

Question 30

Full agonist

Answer 30

Drug that produces a maximal response

Question 31

Partial agonist

Answer 31

A drug with significant affinity bt submaximal intrinsic activity

Question 32

Competitive antagonist

Answer 32

Compound that competes with agonists for the same binding site

Question 33

Non -competitive antagonist

Answer 33

A compound that binds at a different site to the natural receptor and produces a conformational distortion that prevents receptor activation

Question 34

Inverse agonist

Answer 34

A compound that when bound produces the opposite effect to the agonist

Question 35

Volume of distribution

Answer 35

The theoretical volume into which a drug distrubutes following its administration

Question 36

Clearance

Answer 36

The volume of plasma from which a drug is cleared per unit time

Question 37

Context sensitive half time

Answer 37

Time taken for the plasma concentration of a drug to fall by half after the cessation of an infusion designed to maintain a steady plasma concentration