2. Explain why the narrator states that "pesticides were not always thought to

be harmful".

3. How does the chemical solution DDT work?.

4. Explain the relationship between Polio, Typhus, WWII and DDT.

What occurs to the cell during mitosis

Which is an important function of normal flora? a. aid with bone marrow production. b. crowd out pathogenic bacteria. c. destroy digestive track pathogens. d. manufacture iron in the bloodstream.

Cathy hypothesized that corn would not grow in mud. to test this hypothesis, she took corn kernels and placed 5 in mud, 3 in soil, and 2 in water. to her surprise, the kernels in the mud grew faster than the kernels in the soil. what error might have caused these unexpected results? a. wrong hypothesis b. not enough variables c. undefined control d. too many variables