Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Toxicology Exam > Lecture 3-4 Part 1 > Flashcards

Lecture 3-4 Part 1 Flashcards

1
Q

true or false

it is possible for chronic toxic effects to occur some time even after the exposure has stopped

A

true

as in the case of asbestos or cigarettes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

give an example of something that as a high acute toxicity, yet is a benefit in small doses

A

vitamin D

oral LD50 is 10mg/kg

we each require a very small amount (10 micrograms/400IU per day) for good health

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

toxic effects can range from ____ to ____

A

mild allergic reactions to death

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

explain what threshold level is

A

the maximum dose where there are no effects

basically how much the body can tolerate without experiencing any toxic effects (when the defense system gets saturated)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

how to quantify a toxic response

A

the dose response curve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

most tolerant route of exposure

A

the skin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

most popular route of exposure

A

ingestion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

quickest and most direct route of exposure

A

inhalation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is TD

A

dose that results in adverse toxic effect - OTHER THAN DEATH

if it was death it would be LD

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

0 + 2 = >2

what is this and give example

A

potentiation

isopropanol + carbon tetrachloride

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

2 + 2 = 4

what is this and give example

A

additive

ethanol + sedative-hypnotics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

2 + 2 >4

what is this and give example

A

synergistic

ethanol + antihistamine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

2+2 = 0

what is this and give example

A

antagonism

can be functional, chemical, dispositional, or receptor antagonism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

ex of functional antagonism

A

stimulants + depressants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

ex of chemical antagonism

A

metal + chelators

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

ex of receptor antagonism

A

tamoxifen + estrogen - compete for same receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

ex of dispositional antagonism

A

activated charcoal + phenobarbital

absorbs the toxins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

true or false

ADME is part of toxicodynamics

A

FALSE - toxicokinetics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

toxicokinetics or dynamics:

relationship between the external exposure and the dose delivered to the target organ

A

toxicokinetics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

explain toxicodynamics

A

bioochemical response at the target site

(could be a lot of things - cell death, DNA dduct formation, etc)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

following absorption from any route of administration, what happens to the toxin next

A

it enters circulation either directly or indirectly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what is BED

A

biologically effective dose (target organ dose)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is an idiosyncratic reaction

A

individual hypersensitivity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

toxicokinetics is the study of ___ in ____

A

drug disposition in the physiological compartment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

“biotranslocation: is another word for

A

distribution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

toxicity is determined by ____

A

accumulation of the compound in physiological compartments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

how is a normal dosing schedule determined

A

by the chemical’s half life

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

the accumulation of the compound is determined by what 2 things

A

the physiologic compartment and the chemical structure

29
Q

define absorption

A

process by which toxicants cross the body membranes and enter the bloodstrema

30
Q

4 things that can help absorption across the cell membrane

A

diffusion barrier
ion channels
pores
transport

31
Q

2 general transport mechanisms

A

passive transport

specialized (active) transport

32
Q

4 factors affecting membrane transport

A

molecular weight/shape

charge

lipid solubility

membrane composition and thickcness

33
Q

3 main sites of absorption

A

GI tract
lungs
skin

34
Q

acidic compartment traps ___ drugs and basic compartment traps ___ drugs

A

acidic compartment traps basic drugs and basic compartment traps acidic drugs

35
Q

the absorption of most drugs is better and more predictable when administered when?

A

in a fasted state and with a large volume of water

however, drugs that irritate the GI tract should be given with food

36
Q

what can increase the dissolution of basic drugs in the GI tract

A

the presence of food – because it causes HCl secretion

37
Q

what can increase the absorption of lipid soluble drugs in the GI tract

A

stimulation of bile flow

38
Q

define first pass effect

A

removal of orally administered chemicals before they reach systemic circulation

39
Q

generally, orally administered drugs undergo absorption in the ______ and are transported where

A

duodenum and transported to the hepatic portal vein by mesenteric vessels before entering systemic circulation

40
Q

3 ways that 1st pass effects can be avoided

A

giving diff route
give larger dose
give a form of the drug that absorbs more rapidly

41
Q

first pass effect is important consideration for drugs that have a high ___–

A

extraction ratio

(the fraction of oral drug reaching systemic circulation)

42
Q

true or false

the lungs cannot absorb a large amount of toxic substances

A

FALSE

they can - have a very large surface area and a lot of blood flow

43
Q

______ soluble gasses will be readily dissolved in the upper respiratory tract

A

water soluble

bc the upper respiratory tract contains moisture

44
Q

name 2 highly water soluble gasses that will readily dissolve in the upper respiratory tract

A

ammonia and formaldehyde

45
Q

true or false

some toxic substances can cause harm without being absorbed

A

true

46
Q

true or false

pulmonary absorption AVOIDS 1st pass effects

A

true

47
Q

there is equilibrium between ___ and ____

A

blood and tissues

48
Q

what is a chemical’s “plasma half life”

A

time taken for the concentration of the compound in the plasma to decrease by half from a given point

49
Q

what is the most important vehicle for distribution to the body tissues

A

THE BLOOD

50
Q

when the substance is distributed throughout the body, it can be ___, ____, or ____

A

stored, eliminated, or biotransformed (metabolized)

51
Q

2 determining factors of toxin distribution

A

blood flow

affinity for a organ/tissue

52
Q

name 2 things that deposit in bone

A

tetracyclines and heavy metals

also fluoride and lead

53
Q

how does the placenta barrier protect the fetus against toxic chemicals from the mother

A

it has the capability to metabolize

54
Q

3 routes of excretion

A

urinary
fecal
exhalation

55
Q

1st, 2nd, and 3rd most important organs for excretion

A

kidney, feces, lungs

56
Q

define extraction

A

the removal of drug from the blood by an organ

57
Q

ER (extraction ratio) formula

A

ER = (Ca-Cv)/Ca

Ca = arterial drug concentration
Cv = venous blood concentration
aka clearance by the organ/blood flow to the organ

58
Q

when the ER (extraction ratio) approaches 1, what does this mean

A

the clearance by the organ HIGHLY DEPENDS ON BLOOD FLOW. drug is being removed from the blood almost as rapidly as the organ is being perfused by the blood that contains the drug

FLOW DEPENDENT DRUG METABOLISM

59
Q

if the ER (extraction ratio) is very low, what does this mean

A

clearance of the drug by the organ is INDEPENDENT of blood flow

more affected by the activity of metabolizing enzymesd

60
Q

drugs with a low ER are eliminated primarily by ______

A

metabolism

61
Q

3 specific roles of the kidneys

A

filter the blood
reabsorb any useful material
actively secrete things

things filtered/secreted become part of urine

62
Q

bases are excreted better at higher or lower urinary pH?

A

higher

63
Q

acids are excreted better at higher or lower urinary p

A

lower

64
Q

enterohepatic circulation

A

circulation of substances absorbed from the intestine and carried to the liver

at the liver, they are again excreted into the bile and enter the intestine again

65
Q

fecal excretion is through the ______

A

bile

66
Q

the rate of PULMONARY elimination is inversely proportional to…..

A

the blood solubility of the compound

the higher the blood solubility, the slower the rate of pulmonary elimination

67
Q

what is KOW

A

the octanol-water partition coefficient

68
Q
A

Toxicology Exam (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions