2.3

Question 1

What are pesticides?

Answer 1

Chemicals used to eliminate pests, such as insecticides that kill insects and herbicides tags kill weeds.

Question 2

What was introduced to the environment by humans that has caused huge changes?

Answer 2

Synthetic (man made) chemicals.

Question 3

What is bioaccumulation?

Answer 3

The gradual build up of synthetic and organic chemicals in living organisms

Question 4

What goes wrong in order for a chemical to accumulate?

Answer 4

If the chemicals are taken up faster than they are broken down and excreted.

Question 5

How do chemicals enter organisms?

Answer 5

Through food intake, skin contact, or respiration.

Question 6

Can chemicals be stored in the fat tissues of animals?

Answer 6

Yes

Question 7

How do synthetic and organic chemicals effect animals?

Answer 7

They harm the nervous, immune and reproductive systems of animals.

Question 8

What happens if synthetic and organic chemicals are bio accumulated?

Answer 8

They can cause birth defects and cause the animals to be unable to reproduce.

Question 9

What are keystone species?

Answer 9

Species that greatly effect the population numbers and health of an ecosystem.

Question 10

What is a keystone species in British Columbia?

Answer 10

SALMON

Question 11

What is biomagnification?

Answer 11

The process in which chemicals not only accumulate, but become more concentrated at each trophic level

Question 12

When do chemicals bioaccumulate and become biomagnified?

Answer 12

When they are stored in plant tissue and in the fat tissue of animals.

Question 13

How are chemical freed of an animals body?

Answer 13

They have to be broken down for energy

Question 14

What are PBCs?

Answer 14

They are polychlorinated biphenyls, which are synthetic chemicals that were widely used from the 1930s to the 1970s.

Question 15

What were PBCs used for?

Answer 15

Heat exchange fluids, paints, plastics, and lubricants for electrical transformers.

Question 16

What is a half life?

Answer 16

The amount of time it takes for a substance to decrease by half.

Question 17

What effect do PBCs have on humans?

Answer 17

They suppress the immune system and cause cancer.

Question 18

What animals was hit the hardest by PBCs?

Answer 18

ORCA WHALES

Question 19

Why are PBCs so harmful to orca whales?

Answer 19

They are at the top of the food chain in the ocean, so they receive the highest concentration of chemicals like PBCs through bioaccumulation and biomagnification .

Question 20

What class of compounds do PBCs belong to?

Answer 20

Persistent organic pollutants, or POPs.

Question 21

What are POPs?

Answer 21

Carbon containing compounds that remain in water and soil for many years.

Question 22

What is the ,easing way many POPs enter the ecosystem?

Answer 22

Insecticide sprays

Question 23

What is a DDT?

Answer 23

A dichlorodiphenyl trichloroethane, which is an insecticide.

Question 24

Where does DDT bioaccumulate?

Answer 24

In plants, the fatty tissue of animals that eat the plants, in streams, and lakes.

Question 25

How is chemical accusation measured?

Answer 25

In ppm, A.K.A. parts per million.

Question 26

At what level of ppm is DDT considered harmful?

Answer 26

5 ppm

Question 27

What are the effects of DDT on animals?

Answer 27

Causes nervous system, immune system ad reproductive disorders.

Question 28

What are heavy metals?

Answer 28

Metallic elements with a high density that are toxic to organisms at a low concentration. They don’t degrade and cannot be destroyed.

Question 29

Where can heavy metals be found?

Answer 29

In water and in air

Question 30

What are the three most polluting heavy metals?

Answer 30

Lead, Cadmium, and Mercury

Question 31

What level of ppm is lead usually present in?

Answer 31

15ppm - 40 ppm.

Question 32

What was lead used for in the past?

Answer 32

Insecticides, paints, gasoline, lead acid batteries, and electronics.

Question 33

At what level of ppm is lead toxic?

Answer 33

0.0012ppm

Question 34

What effects does lead have on humans?

Answer 34

Anemia, nervous system damage, sterility in men, low fertility rates in women, impaired mental development and kidney failure.

Question 35

Where is cadmium found?

Answer 35

It is found in earth’s crust and is released into the environment by weathering, volcanos, and forest fires.

Question 36

What effect does cadmium have on abiotic and biotic factors of an ecosystem?

Answer 36

It contaminates pa,nuts through take up and then those plants are eaten by animals. It is also toxic to earthworms and other soil organisms at low levels.

Question 37

What effect does cadmium have on humans?

Answer 37

Cadmium poisoning through smoking, infertility, and damage to central nervous systems, immune systems and DNA

Question 38

How much Mercury is released through natural sources (volcanoes, geothermal springs, and rock weathering) each year?

Answer 38

6000 tonnes

Question 39

What percent of mercury released is from coal burning?

Answer 39

40%

Question 40

How does Mercury effect organisms?

Answer 40

It changes compounds, and bioaccumulates in the brain, heart, kidneys and vertebrates.

Question 41

How does Mercury effect humans?

Answer 41

It effects nerve cells, the heart, kidneys, and the lungs. It also suppresses the immune system.

Question 42

What are some of the causes of amphibian loss?

Answer 42

Prolonged drought, increased ultra violet due to depletion of the ozone layer, habitat loss, pollution, over hunting, parasites, and diseases caused by viruses and fungi.