Name ______________________________ Class ___________________ Date __________________
Skills Worksheet
Active Reading
Section: Feeding the World
Read the passage below and answer the questions that follow.
Between 1950 and 1970, Mexico increased its production of wheat eightfold and India doubled its production of rice. Worldwide, increases in crop
yields resulted from the use of new crop varieties and the application of
modern agricultural techniques. These changes were called the green
revolution. Since the 1950s, the green revolution has changed the lives of
millions of people.
However, the green revolution also had some negative effects.
Most new varieties of grain produce large yields only if they receive large
amounts of water, fertilizer, and pesticides. In addition, the machinery,
irrigation, and chemicals required by new crop varieties can degrade the soil
if they are not used properly. As a result of the overuse of fertilizers and
pesticides, yields from green revolution crops are falling in many areas.
Grain production in the United States has decreased since 1990, partly
because the amount of water used for irrigation has decreased during the
same period.
IDENTIFYING MAIN IDEAS
One reading skill is the ability to identify the main idea of a passage. The main
idea is the main focus or key idea. Frequently, a main idea is accompanied by
supporting information that offers detailed facts about main ideas.
Write the letter of the term or phrase in the space provided, that best completes
each statement.
_____ 1. Between 1950 and 1970, the green revolution led to
a. increases in crop yields worldwide.
b. the failure of new crop varieties.
c. water shortages in the United States.
d. grain shortages in Mexico and India.
_____ 2. Irrigation refers to
a. varieties of crop yields. c.fertilizer used to increase crop yields.
b. water used for crops.
d. machinery used to harvest crops.
_____ 3. According to the passage, one problem with the green revolution is that
a. few people have access to new techniques and machinery.
b. it did not last long enough to make a difference in grain production.
c. it led to widespread drought.
d. it led to the overuse of fertilizers and pesticides.
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Food and Agriculture
Name ______________________________ Class ___________________ Date __________________
Active Reading continued
VOCABULARY DEVELOPMENT
Read the following question and write the answer in the space provided.
4. The verb yield means “to bear or bring forth as a natural product.” Use this
information to define crop yield.
_______________________________________________________________
_______________________________________________________________
RECOGNIZING SIMILARITIES AND DIFFERENCES
One reading skill is the ability to recognize similarities and differences between
two phrases, ideas, or things. This is sometimes known as comparing and
contrasting.
Read each question and write the answer in the space provided.
5. How did Mexico benefit from the green revolution between 1950 and 1970?
How did India benefit?
_______________________________________________________________
_______________________________________________________________
6. How was agriculture after the green revolution different from agriculture
before the green revolution?
_______________________________________________________________
_______________________________________________________________
RECOGNIZING CAUSE AND EFFECT
One reading skill is the ability to recognize cause and effect.
Read each question and write the answer in the space provided.
7. What do new varieties of grain require to produce large yields?
_______________________________________________________________
8. Why has grain production in the United States decreased since 1990?
_______________________________________________________________
9. Why are yields from green revolution crops falling in many areas?
_______________________________________________________________
10. What effect do the machinery, irrigation, and chemicals required by new crop
varieties have on soil?
_______________________________________________________________
_______________________________________________________________
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Holt Environmental Science
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Food and Agriculture
TEACHER RESOURCE PAGE
biological control methods will there- fore
not affect non-targeted species.
18 Even if a few individuals are not harmed
by the chemicals, these indi-viduals will
grow and reproduce into a new population
that may be resistant. Then we must
develop new chemicals to kill the newly
resistant population.
19. Mixing organic matter (stems and roots of
previous crops, crops planted to be turned
back into the ground, compost, or manure)
into the soil helps loosen topsoil so water
can soak in and not run off. It also feeds
earthworms, which open the soil, allowing
water to drain into it. Plowing along the
contour and planting contour strips with
grass helps trap any water running
downhill.
20. The most common examples are cat-tle,
sheep, goats, pigs, chickens, horses,
donkeys, and mules. Livestock are raised
for meat, leather, wool, milk, and eggs;
these are the primary uses provided in
developed countries. People in developing
countries are much less likely to use
livestock for meat. Livestock in
developing coun-tries (and sometimes in
developed ones) are often raised to serve
as draft animals, and to provide manure
for fertilizer or to be used as a source of
fuel. In Africa, Masai herders drink blood
from cattle.
8. The amount of water for irrigation is
decreasing.
9. Pesticides and fertilizers are overused.
10. They can degrade the soil if they are used
improperly.
SECTION: CROPS AND SOIL
1. A pest is an organism that exists where it
is not wanted or in large enough numbers
to cause economic damage.
2. insects, plants, fungi, and microorganisms
3. c
4. Insects eat about 25 percent of crops in
Kenya and about 13 percent of crops in
North America.
5. Crop plants grow together in large fields,
providing pests with a one-stop food
source.
6. WP
7. CP
8. WP
9. WP
10. CP
11. Insects in tropical climates grow and
reproduce faster than they do in other
climates.
12. Pest populations cause economic dam-age
and damage to the food supply.
SECTION: ANIMALS AND
AGRICULTURE
1.
2.
3.
4.
5.
Active Reading
SECTION: FEEDING THE WORLD
1. a
2. b
3. d
4. Crop yield refers to how much prod-uct
a crop gives.
5. Mexico increased its wheat production
eight-fold. India doubled its rice
production.
6. After the green revolution, large amounts
of chemicals were used to foster the
growth of new crop vari- eties. Modern
methods and machinery also gained
popularity.
7. large amounts of water, fertilizer, and
pesticides
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
a
c
b
a
Aquaculture involves raising organ- isms
(primarily fish) that live in water.
d
c
a
b
2
5
1
6
3
4
The water brings in oxygen and sweeps
away carbon dioxide and fecal wastes.
They return to reproduce.
Original content Copyright © by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.
Holt Environmental Science
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Food and Agriculture