Final exam up till radiation

Question 1

what is BCF

Answer 1

the tendency for a substance in water to accumulate in organisms

When exposed for a long enough period of time eq will be reached
lab baised

Question 2

How do you determine BCF

Answer 2

Internal concentration / external concentration

Question 3

what is BAF

Answer 3

provides a ratio between the chemical conc in an envoirnment and what is found within the wildlife
feild baised

Question 4

what is biomagnification

Answer 4

increases in conctrations of substances as you move up the food chain

Question 5

how does bioacculmation differ in contaminates that are readily water soluble rather that lipophilic compounds

Answer 5

they undergo carrier mediated uptake bc they cannot readily diffuse across the lipid bilayer

Question 6

how does BCF charts correlate to accumulation

Answer 6

the stepper the chart the more the substance accumulates

Question 7

why is bioaccumulation so important

Answer 7

bc if a compound is found to have a high BCF then low concretions in the environment can result in high concretions in the host tissue

Question 8

what makes a substance toxic under CEPA guidlines

Answer 8

Have a harmful effect on the environment or its biological diversity

may cause danger to envvoinment on which life depends

may cause danger to human health or death

Question 9

what is the Octanol-water Partition Coefficient

Answer 9

measurement of lipophilicity and hydrophobicity which can be determined by dissolving octanol and water into a flask along with a orgnic soild, after which mesuring the conc of the organic soild in both the liquids to determine which has accumulated more, a low value means greater hydraulicity

Question 10

what is the realtionship between BCF and high Octanol-Water Partition

Answer 10

the BCF will be high if the Octanol water partition is high, this is bc lipophillic substances tend to accumlate in greater conctrations in tissue

Question 11

what is the priority substances list

Answer 11

contains substances which are to be assessed to determine if they pose a health risk to humans

Question 12

Organophosphate insecticiides

Answer 12

AChE breaks down acetylcholine which is a neurotransmitter which can buildup at nerve ending effecting neural implusise

Question 13

what is normalization

Answer 13

means adjusting values measured on different scales to notionally common scale for comparsion

Question 14

what is the toxic model approach

Answer 14

ratio concentration to defined endpoint

Question 15

how to calculate toxic unit approach

Answer 15

find the toxic units for both contaimates

A= concA/LC50A
B= conc B/ LC50B

toxicity is then the meaure of tuA+tuB
LC50 is reached when sum of TU is = 1

however this can only be applied is addivtive sitiutations

Question 16

what are the 2 main types of radaition

Answer 16

non-ionizing which is safer to us

ionizing which is much less safe and has mutagentic effects

Question 17

what kind of particles produce ionizing radiation

Answer 17

x-ray and gamma ray

Question 18

what kind of praticles produce nonionizing radation

Answer 18

Sound, electric, radio

Question 19

what are some factors which make radiation dangerous

Answer 19

Penetration and ionization

Question 20

what the 2 majour ways in which radation can infience damage on our cells

Answer 20

Mutagenic- tagrets genes
Cacinogenic- causes cancer

Question 21

differentiate between alpha beta and gamma radiation

Answer 21

alpha- 2 protons and 2 neutrons which has a low penetraticng ability but interacts strongly with matter

Beta- neg eletronsg which morderate penitatration

Gamma- no mass, huge penitration ability

Question 22

what are free radicals

Answer 22

An atom of moleucle w a unpaired electron in outer shell making it very reactive, this can reslut from radiation.