2/6 A/B DayLEQ: What things can change the impactthat a chemical has on a living thing?1. What is a carcinogen?2. What causes FAS?3. What disease is associated with cholesterol?4. What disease is associated with levels ofglucose and insulin in the body?5. What disease is associated with inflamed orswollen bronchi?
Today’s LEQ: What things can change the impact that a chemical has on a living thing?By the end of today, you should be able to…1. Describe how changing the dose, exposure, concentration, potency, and concentration of a chemical can change the impact a chemical has on an organism.2. Explain why the eagle population dropped so dramatically in the United States!
Eagles in trouble…The bald eagle, our national bird, is theonly eagle native to North America.Bald eagles are found throughout most of the UnitedStates. Their most important food source is fish, whichthey catch with their talons. Beginning in the 1950s and60s, the bald eagle population started to decrease, and in1967, the bald eagle was declared an endangeredspecies. Scientists eventually discovered the cause of therapid decline in the bald eagle population, but it wasn’tuntil 2007 that the bald eagle was officially removed fromthe endangered species list. What was the cause of thenear-extinction of bald eagles? Stay tuned to find out!
Possible Killers: Make a hypothesisHunting by humansHunting by other animalsDisappearing food sourceHarmful chemicals in habitatGlobal Warming/Climate changeDisappearing habitat (Deforestation)Disease
1. When was the Bald Eagle population the lowest?2. What do you think caused the Bald Eagle population to suddenly decrease?3. Why do you think it took longer for the Bald Eagle population to go back up again? Eagles (thousands) Number of Bald 1940 ‘50 ’60 ‘70 ‘90 2000 ‘10
Make a FRAYER DIAGRAM for each VOCAB WORD(dose, potency, exposure, susceptibility, concentration) DEFINITION: Sentence: (CREATE YOUR (Write definition of OWN SENTENCE the word from the using the word) station) EXAMPLE: DOSE CLUE!!! Come see me—I will give (Write the example you the clue to help solve of the word from the mystery! Copy all of the station) the important clues here!
Discovery EducationDDT: A Threat to America’s Bald Eagles
Let’s Practice: Fill in the blank! Beginning in the 1950’s, scientists started spraying large DOSES _________ of DDT into the environment. DDT is a chemical with a very high POTENCY meaning it is extremely ________, powerful, even in small amounts. As humans continued to spray DDT into the environment, we quickly learned that the _______________ of the chemical increased as it traveled CONCENTRATION higher up the food chain. Small organisms, like insects, would only have a small percentage of DDT in their bodies, but the organisms at the top of the food chain would eat millions of smaller animals, which would greatly increase the amount of the chemicals in their bodies. OrganismsEXPOSURE to the chemical continued to increase because the ________ chemical did not disappear once it was sprayed into the environment. Because different organisms have a different SUSCEPTIBILITY ______________ to the chemical, not all of the eagles died.
EOG QUESTIONWhich factor best explains why some peoplewill develop cancer and others will not afterbeing exposed to the same high levels of aharmful chemical? a) concentration of the chemical b) potency of the chemical c) individual susceptibility to the chemical d) individual exposure to the chemical
DDT: Pros and ConsDo you think we should lift the bans on DDT? Why or Why not?!
Summarizer:1. Increased exposure to a chemical would [increase/decrease] your chance of getting sick.2. Would you rather be exposed to a high dose of a dangerous chemical or a low dose of a dangerous chemical?3. If everyone is exposed to the same amount of a dangerous chemical, why won’t everyone get sick?4. Eagles have a [higher/lower] concentration of DDT in their bodies than insects do.5. Which would you predict to be more potent: bleach or water? Why?