Unit C Section 3.3

Question 1

What is Biomagnification?

Answer 1

Biomagnification is the increase in the concentration of a chemical or element as it moves up the food chain

Question 2

Example of biodegradation?

Answer 2

-The mercury falls onto fresh or saltwater where
bacteria join it to an organic molecule that algae can absorb. (Any one algal organism isn’t affected by the mercury because it takes in very little.)
It enters the food chain and increases when more organisms eat the organisms that contain the mercury

Question 3

What are the two ways mercury can enter the water?

Answer 3

• is from the air as a result of emissions from industrial plants.
• from industrial waste fluids

Question 4

What is crude oil?

Answer 4

• Crude oil is a mixture of many chemicals
• For example, paraffin wax and asphalt are very large hydrocarbon molecules.
• Methane is a small one.
• Some molecules in crude oil contain atoms of nitrogen, oxygen, and sulfur

-it must be processed in an oil refinery.

Question 5

What happened to the Exxon Valdez

Answer 5

The Exxon Valdez spilled approximately 260 000 barrels (41 337 m3) of crude oil into the Prince William Sound.

Question 6

How does the composition of oil change after it is spilled?

Answer 6

• The lighter and smaller molecules disperse into the air or water.
• “Tar balls” of heavy hydrocarbons are washed ashore or sink into the sediment below the water.
• Bacteria are able to degrade some of this oil for use as food.

Question 7

How toxic are hydrocarbons?

Answer 7

some hydrocarbons are toxic in

concentrations as low as 1 pp

Question 8

How harmful is oil to the environment?

Answer 8

oil can persist in the

environment for more than 10 years.

Question 9

What happened to the spilled oil?

Answer 9

50%- biodegraded/degraded by light in water
20%-degraded by light in air
14%-recovered
13%-deposited in subtidal sediment
2%- traveled to the shore
1%-dispersed in water

Question 10

Which organisms were affected by the Exxon Valdez oil spill?

Answer 10

-Floating algae were killed.
-Invertebrates near-shore ( lack of oxygen and food and toxic effects of hydrocarbon
-Fish eggs and young fish (sensitive to the toxic chemicals in the oil.)
-Pacific herring and pink salmon fry died (or were
physically deformed)
-Seabirds and mammals became covered with oil

Question 11

how were people affected by the Exxon Valdez oil spill?

Answer 11

• commercial fishers could no longer fish
• People who relied on wildlife for their food had to purchase more expensive groceries from stores

-The tourist trade decreased dramatically
- (campers and kayakers) chose not to come to the
contaminated area.

Question 12

In Alberta, companies are supposed to report what amount of spills?

Answer 12

In Alberta, companies are required to report spills greater than 2 m.

Companies and governments have emergency response plans in place.