lesson 2 unit 2

Question 1

water table

Answer 1

the top zone of soil and rock where water fills voids. In other words, it is water under the surface that will eventually make its way into open water sources.

Question 2

dichloro-diphenyl-trichloroethane, better known as DDT

Answer 2

This pesticide was widely used to control insect populations, particularly mosquitos and flies.

Question 3

`ecosystems

Answer 3

a community of interdependent organisms in an environment

Question 4

ozone layer

Answer 4

This layer of air forms a barrier between the Earth’s atmosphere (what we breathe) and the sun. It is about 15 miles above the Earth’s surface. Without the ozone layer, we would be subject to the direct rays of the sun, which would be more than life on Earth could handle. Scientists noticed the thinning of the ozone layer in the early 1970s and have been contemplating how to manage this change ever since. As more sun gets through, the Earth becomes warmer.

Question 5

greenhouse effect

Answer 5

The sunlight goes through the car’s window into the car, but the glass prevents the hot air from leaving the car