Download Unit B – Plants for Food and Fibre

Unit B – Plants for Food and Fibre
Section 1 - Understanding Structures and Life Processes of
Plants Helps us Interpret their Needs
Subsection 1.1 - The Body of Seed Plants
Seed plants are plants that make seeds. Seed plants come in all
shapes and sizes (cottonwood tree, daisy, grass), but they all have 4
major parts that are the same.
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Subsection 1.2 - Plant Processes
Photosynthesis and cellular respiration review.
How Materials Enter and Leave Plants
 The movement of material from the soil into the plant involves
three processes:
A. Transpiration is the evaporation of water from the surface of
the plant. This usually occurs through tiny holes in the leaves
called stomata (stoma).
Water vapor leaves
the leaf through the
stomata.
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B. Diffusion is when materials (usually dissolved in water) will
move from an area of higher concentration to an area of lesser
concentration until equilibrium (a balance) is met. In plants
this happens through the semi-permeable membrane of the root
cells.
The diffusion of water is called osmosis.
Soil
Roots
water
semi-permeable
membrane
C. Capillary action is the attraction of water particles to other
water particles and surfaces. When some particles move by
diffusion to another part of the plant other particles are pulled
along with them.
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Section 1a Assignment – Plant Processes
(In your own words)
1. Explain where, why and how transpiration happens. Use a
diagram to show what you are explaining. /4
2. Explain where, why and how diffusion happens. Use a
diagram to show what you are explaining. /4
3. Explain where, why and how capillary action happens. Use a
diagram to show what you are explaining. /4
4. Identify the four parts that a dandelion and an apple tree have
in common. Describe the function of each part. /4
Subsection 1.3 - Reproduction of Seed Plants
A life cycle refers to the stages of development that an organism
goes through in its life. In plants it looks like this:
seed
Starts to grow.
pollination
seedling
Grows and develops
reproductive structures.
adult
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Seed Plant Reproduction
Plants can reproduce in one of two ways:
1. Asexual Reproduction – Does not involve any exchange of
genetic material from the parent plants. (ex-cutting)
2. Sexual Reproduction – Involves the union of the sperm and egg
cells from the male and female parts of a flower to produce a
seed.
A. Asexual Reproduction in Flowering Plants
Forms of Vegetative Reproduction
1. Cutting – taking part of a
5. Cloning – taking a single
plant (root, leaf) and
cell from an organism and
planting it. This will grow a
generating another organism
genetically identical plant.
identicle to the original.
2. Bulbs – short underground
stems that are rounded or
bulb shaped. (ex – tulips,
onions)
3. Runners – part of the root
system that reaches the
surface and starts a new
plant. (ex – grass, trees)
4. Grafting – a cutting from
one plant is attached to
another plant (ex – apple
trees).
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B. Sexual Reproduction in Flowering Plants
The Male Part of the Plant
Stamen – The stamen is made up of 2 parts:
1. Anther – It produces and stores the pollen grains.
2. Filament – It holds the anther out in the open.
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The Female Part of the Plant
Pistil – the pistil is made up of the following 3 parts:
1. Stigma – Produces a sticky sugar a) so that the pollen grains
will stick to the stigma b) to nourish the pollen grain so that
it grows a pollen tube that reaches the ovary c) to attract
pollinators.
2. Style – The style holds the stigma up in the open in order to
be more exposed to pollen grains and pollinators.
3. Ovary – The ovary houses all of the egg cells. This is
where fertilization occurs.
Other Parts of the Plant
Petal – Coloured brightly to attract pollinators
(birds and insects).
Sepals – Help protect the flower before, during and after
blooming.
Subsection 1.4 - Plant Structures are Adapted to Their
Environment
In order to survive in their environment, plants must be adapted to
that environment. They will have specific behavioural and
structural adaptations that help them survive.
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 Cacti have thick stems and
small spiny leaves to prevent
water loss.
 Sunflowers have large leaves
to take in the most sunlight
possible for photosynthesis.
 Plants like wild mustard that
live in areas with short
growing seasons will
produce seeds very quickly.
 Plants will close their
stomata in hot weather to
prevent water loss through
transpiration.
 Spruce trees have needlelike leaves with thick
coatings to prevent water
loss.
 Most plants will bend
towards the light to get
sufficient energy for
photosynthesis.
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Subsection 1.5 - Plant Needs and Growing Conditions
Seeds need only the proper temperature and the right amount of
water in order to germinate. Why don't seeds need light?
______________________________________________________
______________________________________________________
Plants need the proper amount of light, water, nutrients,
temperature and space. Different species will have their own
specific requirements.
Light: ferns require less light than a sunflower.
Water: tropical plants need more water and higher temperatures
than plants in southern Alberta.
Nutrients: desert plants need different nutrients than tropical plants.
Space: a cottonwood tree would need more space than a grass plant.
Section 1 Assignment – Plants for Food and Fibre
1. Seed plants all have four structures that are the same. On a spruce
tree two of those structures are a little bit different. How are those
two structures different from other seed plants?
2. There are three processes that move materials in and out of a seed
plant. Which one is responsible for moving water from the roots to
the leaves? Where does this occur?
3. What is the difference between a seedling and an adult seed plant?
4. How is sexual and asexual reproduction different?
5. Draw and label a flower with its reproductive parts. Describe the
function of each.
6. Describe what a cutting is.
7. If there was a plant that lived in a hot and dry climate, describe two
adaptations it may have that would allow it to survive.
8. Why don’t seeds need light in order to germinate?
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Section 2 - Plants Play an Essential Role in the Environment
and in Meeting Human Needs
Subsection 2.1 - The Role of Plants in The Environment
Textbook page 127
We must make sure the needs of plants are being met so we can
continue to benefit from them now and in the future.
 List and describe how we benefit from plants:
_____________________________________________
_____________________________________________
_____________________________________________
_____________________________________________
_____________________________________________
_____________________________________________
_____________________________________________
_____________________________________________
Subsection 2.2 - We Use Plants in Many Ways
Aboriginals were one of the first to use plants as food and
medicine for such illnesses as rheumatism and scurvy. What are
some other ways aboriginals used plants?
Subsection 2.3 - Managing Living Resources
Living resources are living things that can be used for the benefit
of humans. If we fail to manage the use of these resources then we
may use them up or interfere with their ability to survive.
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Title – Effectiveness of Different types of soil
Problem – How well will different types of soil (peat moss, loam,
sand) provide water, nutrients and oxygen for plants?
Hypothesis –
Variables – Manipulated (1), Responding (1) and Controlled (3)
Demo by the teacher
Observations
Title:
Discussion
1. Which type of soil would be the best to grow a garden in ?
Explain three reasons why.
2. Of the three components of good soil (nutrients, water and
oxygen) can you have too much of any of them? Explain two
reasons why or why not.
Conclusion
a) Restate your hypothesis.
b) Were your predictions correct?
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c) Explain how you know you are right/wrong.
Section 3 - Soil is an Important Resource that Human Activity
Can Protect or Damage
Subsection 3.1 - What is Soil
Components of Soil/Dirt:
1. Weathered rocks and minerals.
2. Humus – partially decomposed material (usually
vegetation).
 Soil must provide 3 main substances for the plant:
1. water
2. nutrients
3. oxygen
Characteristics of
Nutrients Air Water Characteristics of
Nutrients Air Water Characteristics of
Nutrients Air Water -
:
:
:
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Fertilizer Use
We add fertilizer in order to return nutrients to the soil for plant
use. There are two kinds of fertilizers:
a) Organic Fertilizer – such as animal waste (manure) or a crop
that is ploughed under.
b) Inorganic Fertilizer – These are manufactured products made
from a number of chemicals.
 Three of the main nutrients that plants need are:
nitrogen (N) phosphorus (P) potassium (K)
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Title – The effect of different fertilizers on the growth of plants.
(grown in soil or hydroponically)
Problem – Will plants grow differently when provided with a fertilizer
rich in __________________ than one rich in _______________?
Hypothesis –
Variables – Manipulated (1), Responding (1) and Controlled (3)
Procedures – as directed by teacher
Materials
Observations
Title:
Control
Discussion
2. Explain why we grew one plant without any fertilizer at all?
3. Which plant had the healthiest root system?
4. Which plant developed flowers first?
Conclusion
a) restate hypothesis
b) were your predictions correct?
c) What information proved that you were wrong/right?
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Subsection 3.2 - Our Practices Can Improve or Degrade Soil
Advantages of Soil Technology
a) Strip Farming – Alternating strips of land are planted with a
crop. The other strips are left alone for a season. The
unplanted strips have stubble which holds the soil together,
prevents wind erosion and returns nutrients to the soil.
b) Plowing – Plowing involves turning over the top soil. This
breaks up the soil and allows more air spaces.
c) Crop Rotation - Growing alternating crops on the same plot
of land that use different nutrients. This prevents the
depletion of particular nutrients in the soil.
d) Irrigation – A method of providing water when there is not a
sufficient amount to sustain the crops.
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e) Fertilizers - added to the soil to replenish nutrient levels.
f) Zero Tillage – Planting a crop without disturbing the soil at
all. By not disturbing the soil, erosion by the wind or water is
prevented.
Disadvantages of these Technologies
a) Zero Tillage –Allows the soil to absorb too much water. In
this state weeds cannot be controlled as well.
b) Fertilizer – Run off from crops containing fertilizers end up
in ponds, lakes and rivers. This promotes plant life, which
will in turn use up most of the oxygen leaving none for the
other organisms.
c) Irrigation – When water evaporates from the soil or the
surface of the plant salts are left behind. Too much salt in the
soil can prevent the proper growth of plants.
d) Strip Farming - can be expensive because only half of your
land is being harvested each year.
e) Plowing - Allows for the erosion of soil by wind and water
because the soil is broken up.
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Plants for Food and Fibre - Section 3 Assignment
1. What two things is soil made of?
Rocks and minerals, humus (organic material like…dead plant parts)
2. What is the advantage of using organic fertilizers?
Adding minerals and nutrients to the soil, it’s probably healthier
because it’s natural.
Better way of disposing of the poop.
3. Farmers will usually leave stubble behind after they have harvested a
crop. Describe two ways that this will benefit the soil.
1. prevents erosion from taking away the top soil.
2. returns nutrients to the soil.
3. helps retain snow moisture over the winter
4. Explain why it is important for us to gain a knowledge of soil and how
it best suits the needs of plants?
It’s important to gain knowledge of soil so we know which type of soil
will be best for the plant, and so we can minimize crop inputs (water
and fertilizer).
5. Describe an advantage and a disadvantage of crop rotation.
Advantage: different plants draw different nutrients from the soil.
Disadvantage: specialized equipment required
6. A farmer plants the same crop in one area year after year. What may be
a disadvantage of doing that?
The soil will get depleted (the nutrients that plant needs will get used
up)
7. Explain how does an algae bloom happen?
Fertilizer from the fields runs into the lake and feeds algae that covers
the surface of the water.
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8. What type of fertilizer would I use if my plants were not flowering?
Ask the dude. (Mr. Lally)
9. What three things must good soil provide for plants?
1. Nitrogen N
2. Phosphorus P
3. Potassium K
1. Water
2. nutrients
3. oxygen
Section 4 - The Way that Plants are Grown
Subsection 4.1 - Modifying Environments to Increase Yields
The yield refers to the amount of useful material you can get from
one plant. As our populations grow so does our need for greater
yields from plants.
Hydroponics is a method of growing plants without soil. The
plants are placed in a medium that is supportive and water with
dissolved nutrients are pumped through regularly. The advantage
is that every thing is controlled and you can grow anything
anywhere. The disadvantage is that it is very expensive.
4.2 - New Plant Varieties are Developed by Selective Breeding
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Each species of plant may have different varieties. Each variety
will have its own specific characteristics or traits.
New plant varieties are produced to provide us with plants that
have the traits that we need or want.
Selective breeding is a process by which people select plants with
specific characteristics that we like or need and breeding them
together (pg 158 Fig 4.12).
Genetic engineering is a process by which single genes are added
to plant cells so they will develop specific characteristics.
 New varieties can cause new problems in the environment.
4.3 - Controlling Weeds and Pests
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Pest - any organism that humans consider to be a problem.
Pesticides – chemicals designed to get rid of pests.
a) insecticides –designed to get rid of insect pests.
b) herbicides –designed to get rid of plant pests.
c) fungisides –designed to get rid of fungus pests.
Biological Control – the use of other living things to get rid of
pests (ex - cats to control number of mice).
Monoculture is the growth of just one species of plant (a farmer's
crop). Monocultures are easier to manage but may provide an easy
sourse of food for pests.
Section 4 Assignment
1. Exlain how selective breeding and genetic enginering are
different.
Selective breeding, selecting 2 plants to breed. (sexual)
Genetic engineering, isolating genes of 1 plant to develop
desired traits. (asexual)
2. Give three reasons why someone would use selective
breeding?
1. increase yield
2. bigger plant
3. cheaper than G.E.
4. disease resistance
3. Explain two reasons why genetic enginering would benefit
humans.
1. disease and pest resistance
2. increasing yield
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3. speed of production
4. Explain two reasons why genetic enginering may be a bad
thing for us including the environment.
1. cost
2. mistakes
3. risks in developing “super plants.”
4. wipe out a species
5. Do you think selective breeding and genetic enginering are
sustainable technologies?
Yes, because
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