Pesticides

Question 1

Some pesticides have had longer-term harmful effects because they remained in the environment after they were no longer needed, so today most pesticides are designed to last how long? They are broken down by what so that they are no longer toxic?

Answer 1

Only one growing season. Bacteria.

Question 2

Shorter-lasting pesticides may cause what to develop.

Answer 2

Pesticide resistant pests.

Question 3

Example of resistant pests.

Answer 3

Insects reproduce rapidly, so many generations can be exposed to an insecticide in one season. Some of these insects may be resistant to the insecticide. If they survive and reproduce, the whole population could become insecticide-resistant.

Question 4

Scientists are finding that water samples may contain what? Why is it harmful?

Answer 4

Very low concentrations of many different pesticides. Several pesticides together might mix to form a much more toxic or poisonous substance.

Question 5

Define toxicity

Answer 5

Toxicity describes how poisonous a
substance is.