C H A P T E R
16
Overall Expectations
Briefly explain each of the following points.
• Plants obtain nutrients from their
environment and provide energy and
nutrition to other organisms. (16.1)
• Soil is composed of broken rock, humus,
and living organisms, and it provides the
essential nutrients needed by plants. (16.1)
• Plants are made of organic matter and they
store carbon in their tissues. (16.1)
• Primary succession is a sequence of changes
in a community that starts with bare rock
and ends with a stable ecosystem. (16.2)
• Secondary succession is a sequence of
changes in a community that begins with a
previously existing but disturbed
community and ends with a stable
ecosystem. (16.2)
• The final stage of succession is called a
climax community. (16.2)
• The agricultural revolution refers to the
change from a nomadic lifestyle of huntergatherers to a lifestyle where humans are
able to control the growth of plants for
food. (16.3)
• Monoculture is the practice of farming large
plots of land with a single crop plant. (16.3)
• Many farming practices deplete minerals in
the soil, so various methods are used to
R E V I E W
replenish those nutrients, including crop
rotation, and farm manure technology. (16.3)
• There are many different technologies for
controlling pest organisms. Each method
has advantages and disadvantages. (16.3)
• Some plants can be grown without soil
using soil-free hydroponics. (16.3)
• Abundance of food resulting from advanced
agricultural processes has shaped our
current society. (16.4)
• Modern agricultural technology is not very
energy efficient. (16.4)
• The use of water for irrigation can have
negative consequences on both the water
and the irrigated soil. (16.4)
Language of Biology
Write a sentence using each of the following words or
terms. Use any six terms in a concept map to show
your understanding of how they are related.
•
•
•
•
•
•
•
•
•
soil
humus
organic matter
carbon sink
primary succession
secondary succession
climax community
agricultural revolution
monoculture
•
•
•
•
soil fertility
crop rotation
biomagnification
integrated pest
management (IPM)
• soil-free horticulture
• hydroponic culture
• aeroponic culture
UNDE RSTAN DIN G CON CEPTS
1. What role does the plant kingdom play in the
biosphere?
(a) Agricultural technology has caused the
productivity of the land to decline.
(b) Nomadic hunter-gatherers invented
agriculture.
2. Write one or two sentences to answer each of
the following questions.
(a) What do plants need for growth?
(b) What do plants do for the biosphere?
(c) What do plants do for us?
(d) What do we have to do to support the
needs of plants?
5. List the nutrients that plants must obtain from
the soil in which they grow. What soil nutrient
cannot be obtained from rock particles? What
nutrient is most likely to be depleted by the
growing of crops?
3. Define “technology.” Give two examples of
plant-based technology, one ancient and one
modern.
6. List some methods of restoring the fertility of
depleted soil. What method is most commonly
used by large factory farms?
4. In your notebook, state whether each of the
following statements is true. Rewrite any false
statement to make it true.
7. Define “pesticide.” Compare the value of
pesticide use to its drawbacks. List some
alternatives to the intensive use of pesticides.
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8. For each of the following pairs of terms, state
what the terms have in common and explain
how they differ.
(a) hydroponic, aeroponic
(b) commercial chemical fertilizer, farm manure
(c) pesticide, fertilizer
(d) pesticide, integrated pest management
9. Why do most farmers use fertilizers either
after harvesting a crop or just before planting
a new one?
10. What is the main goal of all plant technologies?
Describe the impact of these technologies on
the biosphere.
13. List the main components of soil. What role do
plants play in making soil?
14. What is the goal of monoculture? List the main
advantages and disadvantages of this
technology.
15. Explain how the following statements might
contradict each other, even though both are
true.
• Farmland is much more productive than at
any time in the past.
• We are growing more food on less land and
feeding more people yet more people are
going hungry.
16. Modern farming technology is often described
as highly efficient compared to the technology
used 100, 1000, or 10 000 years ago. This claim
is only half true. What aspect of modern
farming is genuinely more efficient? What
aspect is much less efficient?
11. In integrated pest management, what is
integrated? Give some specific examples to
support your answer.
12. According to scholars, when did agriculture
first emerge? Explain why they cannot be
absolutely sure.
IN QU IRY
17. Find out the price per kilogram of fresh
pineapple flown from Hawaii. Using this rate,
calculate how much it would cost for you to
take a return trip to Hawaii. Compare this
calculated rate to advertised return-trip fares.
How can growers afford to transport pineapples
by air?
18. A sign about 30 km from the outskirts of a large
city says “Experimental poplar plantation
planted and raised using reclaimed water and
biosolids.”
(a) Interpret the term “reclaimed water.” What
do you think is the source of the reclaimed
water?
(b) Interpret the term “biosolids.” What do you
think is the source of the biosolids?
(c) In your opinion, what is the point of this
experiment? Give reasons to support your
opinion.
(d) Poplar trees grow quickly, but their wood is
not very strong. What is a possible use for
these trees when they are mature enough to
be harvested?
19. Some flowers were planted outside in spring in
southern Ontario. Each plant was measured
weekly, and the average growth per week and
the average total growth per week were
recorded in the table shown here. When was
the growth of the plants the greatest? Now
create a graph that shows the new growth and
610
MHR • Plants: Anatomy, Growth, and Functions
the total growth of the plants. Can you see on
your graph where the growth of the plants was
greatest? where it was the smallest? What
might explain the lack of growth in Week 3?
New growth each week
(in centimetres)
Total growth
(in centimetres)
Week 1
1
1
Week 2
3
4
Week 3
0
4
Week 4
3
7
Week 5
2
9
Week 6
4
13
Week 7
5
18
Week 8
5
23
Week 9
6
29
Week 10
4
33
Time
COMMU N ICATIN G
20. Soil has been described as “the ultimate
resource.” Develop an argument to support this
statement. Develop a counter-argument in
favour of some other resource that could
reasonably be regarded as the “ultimate” one.
21. Describe the possible places where the calcium
found in your bones may have been. Draw a
nutrient cycle to help explain your answer.
M A KIN G CON N ECTION S
22. Sketch a diagram of secondary and primary
succession. Use these diagrams to compare the
two processes of succession. What does the
final ecosystem resemble in both of these
successional areas? Explain your answer.
23. Create a flowchart that describes the steps a
farmer might take to increase the yield from
her crops if (a) the yield is low because of poor
soil fertility, and (b) the yield is low because
of a pest problem. Be sure to include the steps
that help decide either why the soil is not
fertile, or the steps to determine which pests
are present.
24.
25 ppm in birds
like the osprey
25. An ever-increasing human population size is a
threat to the continued existence of the human
species, Homo sapiens.
(a) Under what conditions is this statement
likely to be true?
(b) What could be done to ensure that this
statement proves to be untrue?
26. Identify trade-offs in the development of food
technologies and explain the motivation
behind the trade-offs. For example, explain
why vegetable growers might prefer varieties
that travel well over those with more flavour or
nutritional value.
27. What trade-off in the development of food
technologies do you find most alarming? State
your reasons. How did the decision to make
this trade-off get made? by whom? Must we
keep on making this trade-off? Could the
original decision be reversed or modified?
28. What unique problems make plant
technologies more difficult to influence or
control than other technologies, such as
computer or communications technologies?
2 ppm in large fish
0.5 ppm in
smaller fish
0.04 ppm in
zooplankton
up to 0.003 ppm in water
Refer to this figure and write an explanation of
what is happening. How could this affect
human populations? Create a diagram of the
process of biomagnification that could occur in
a terrestrial environment.
29. Noted environmentalist and broadcaster David
Suzuki has said that human biology is an
integral part of the global ecosystem. Do you
agree?
30. Imagine it is 2042 and you have just retired.
Your grandchildren want to know what the
biosphere was like when you were growing up.
What will you tell them? What would you
expect to hear if you asked people of your
grandparents’ age that question today?
31. Consumers want fresh produce of consistent
quality at low prices. The agricultural industry
wants crop plants to generate a high yield at
the lowest possible cost. Are these goals
compatible? Or are we making trade-offs that
will eventually prove unfavourable to the
biosphere and our own health for the sake of
low prices and convenient technology? Think
about this issue, and write down your opinion
about it.
Plants and Their Environment • MHR
611