Chapter 23 Flashcards Preview

AP Earth Science > Chapter 23 > Flashcards

Flashcards in Chapter 23 Deck (21):
1

pest

is any species that competes with us for food, invades lawns and gardens, destroys wood in houses, spreads disease, invades ecosystems, or is simply a nuisance.

2

natural enemy

(predators, parasites, and disease organisms) control the populations of about 98% of the potential pest species as part of the earth's free ecological services and thus help keep any one species form taking over for very long.

3

pesticides

chemicals to kill or control populations of organisms we consider undesirable.

4

insecticides

chemicals that kill insects by blocking reproduction, clogging their airways, or disrupting their nervous system

5

herbicides

chemicals that kill weeds by disrupting their metabolism and growth

6

fungicides

fungus killers

7

rodenticides

rat and mouse killers

8

biocide

is a more accurate name for these chemicals because most pesticides kill other organisms as well as their pest targets.

9

second generation pesticides

they are composed of synthetic organic compounds.

10

DDT (dichlorodiphenyltrichloroethane)

a synthetic organic used as an insecticide. Tends to persist in the environment and become concentrated in animals at the head of the food chain.

11

broad-spectrum agents

pesticides that are toxic to many species

12

selective or narrow spectrum agents

are effective against a narrowly defined group organisms.

13

persistence

the length of time they remain deadly in the environment

14

pesticide treadmill

whereby farmers pay more and more for a pest control program that often becomes less and less effective.

15

circle of poison

residues of some of these banned or unapproved chemicals exported to other countries can return to the exporting countries on imported food

16

Silent Spring

which warned of the dangers of DDT and other broad-spectrum and persistent pesticides.

17

dirty dozen

list of chemicals that includes DDT and eight other chlorine-containing persistent pesticides.

18

economic threshold

the point at which the economic losses caused by pest damage outweigh the cost of applying a pesticide.

19

cosmetic spraying

extra pesticides are used because most consumers often buy only the best-looking fruits and vegetables even though there is nothing wrong with blemished ones.

20

food irrigation

extends food shelf life and kills insects and parasitic worms (such as trichinae in pork). It also kills harmful bacteria.

21

integrated pest management (IPM)

combined use of biological, chemical, and cultivation methods in proper sequence and timing to keep the size of a pest population below the size that causes economically unacceptable loss of a crop or livestock animal.