Unit b plants for food & fibre

1. Unit B: Plants for
Food & Fibre

2. Parts of a Plant

3. Parts of a Plant
• Flowers
o flower usually has both male and female parts for reproduction
o Bright petals attract insects
• Leaves
o produce food for the plant
o take in carbon dioxide and release oxygen
o allow water to exit the plant

4. Parts of a Plant
• Seeds
o contain an embryo that will form a new plant
o contain a food supply for the embryo
• Cones
o there are separate male and female cones for reproduction

5. Parts of a Plant
• Stems
o provide a pathway for movement of water and food
o support the leaves and reproductive structures
o made of two important tissues:
• 1. Xylem - is used to transport water from the roots to the leaves
• 2. Phloem - transports sugar from the leaves down to the roots
• Roots
o absorb water and dissolved nutrients
o anchor the plant in the soil

6. Seeds
• There are a large number of plants that make seeds.
• Wheat is a seed we eat.
• Dandelion have seeds we play

7. Seeds
• Flowers have seeds.
• So do apples, they grow into apple trees

8. Seeds
• Pine trees have cones
• Cones are also seeds

9. Seed Dispersal Video

10. Plant Processes

11. Transpiration
• Transpiration: is the evaporation of
water from a ​plant, mostly the leaves.
Water particles evaporate from the
surface of the leaves and other water
moves ​up through the plant to take its
place.

12. Capillary Action
• Capillary action: helps to move water
up the tubes ​in the stem of a plant. Like
in a straw water ​molecules are attracted
to the sides of the tube and can ​form a
meniscus. This helps the plant suck up
the ​water like you would use a straw to
suck up a milk ​shake.

13. Diffusion
• Diffusion: is the ​movement of ​particles
from an ​area of high ​concentration to ​an
area of lower ​concentration. Like the
smell of a ​match or a drop of ​perfume.

14. Osmosis
• Osmosis:
o Osmosis is a process where water is moved
into the ​cells of a living organism. If the
concentration of water is greater outside the
cell water will move into the cell to ​make it
equal.
o Osmosis is a form of diffusion with a little
bit extra.
o Osmosis also involves a selectively or semi-
permeable ​membrane.

15. Osmosis
• Semi-permeable membrane:
o It is a ​membrane ​(wall or barrier) ​that will
only ​allow some ​things to pass ​through it,
and ​only at certain ​times.

16. Active vs Passive Transport
• Active Transport
o needs energy because particles ​are moving up, going against gravity! The
farther they ​go, the more energy is required.
o Example: Capillary Action
• Passive Transport
o no energy is required.
o Examples: Diffusion and Osmosis!

17. Photosynthesis
&
Cellular Respiration

18. Photosynthesis
• Photosynthesis
o is a complex reaction. Using energy from the sun, a
plant can transform carbon dioxide and water into
glucose (sugar/food) and oxygen
o Equation:

19. Photosynthesis
• Leaves are the main parts that perform
photosynthesis. Plant cells have small parts that
are called chloroplasts. These chloroplasts have a
green pigment called chlorophyll that helps
capture the sunlight.
• Chloroplasts: part of a plant cell where
photosynthesis happens
• Chlorophyll: green pigment that helps capture
the sunlight.

20. Photosynthesis
• The plant cell is surrounded by a
membrane that has pores, or tiny
openings. Particles of some substances
are able to move in and out of a cell
through these pores. The cell
membrane acts as a filter, keeping
some substances inside the cell and
allowing some substances to move in
and out of the cell. Many processes
take place to move substances in and
out of plant cells.

21. Cellular Respiration
• Cellular Respiration
o Cellular Respiration is a process in which an ​organism
combines glucose (food) with oxygen to ​create energy
and expelling carbon dioxide and water ​as waste. It is
the exact opposite of photosynthesis.
o Equation:

22. Photosynthesis & Cellular Respiration
• Gas Exchange
o is the process of these
gases entering and
leaving the plant.

24. Photosynthesis & Cellular Respiration
• Producers vs. Consumers
o Plants are producers because they make their
own ​food or energy from sun light
through ​Photosynthesis.
o Most other organisms are consumers. Consumers ​need
to eat something else to get energy and most of ​them
use the process of Cellular Respiration.
o Plants also use the process of cellular respiration to
use the ​glucose (food) they have made
through ​Photosynthesis.

25. Plant Reproduction

26. Plant Life Cycle
• Plants like humans have a life cycle.
• Life Cycle: is the stages that a living thing passes through to go
from one generation to the next.
1. They start as seeds.
2. When a seed starts to grow it becomes a seedling.
3. When seedling grows and develops reproductive ​structures it
becomes an adult plant.
4. When an adult plant is pollinated it then makes its ​own seeds and
restarts the cycle.

27. Plant Life Cycle
• Draw the plant life cycle

28. Stages of a plant
• Plants like humans have a life cycle.
• Seed Stage: A seed has three main parts: the embryo, stored food,
and a seed coat
• Seedling Stage: grow very fast and produce new leaves, roots, and
stems. They produce their own food by photosynthesis and use
nutrient from soil.
• Adult Stage: produces reproductive structures. For seed plants,
these structures are either a flower or a cone.

29. Pollination
• Plants like humans have a life
cycle.
• Pollination: is the transfer of
pollen from a male part of a
plant to a female part of a plant,
later enabling fertilization and
the production of seeds, most
often by an animal or by wind.
• Pollinators: organisms that
carry pollen from one flower to
another

30. Pollination
• Stamen:
o is the male structure.
o The top, the anther, contains the
pollen (sperm).
o The filament is a long stem that
helps the pollen to reach wind or
pollinators.
• Pistil:
o Is the female structure
o Stigma - sticky top that collects
pollen
o Style - long tube part

31. Pollination
• The ovary contain the ​ovule
(the female ​reproductive
organ) The pollen moves
to ​the stigma, from the ​stigma
it travels down ​the pollen
tube to the ​ovule were a
seed ​starts to develop.
• Draw this picture in your
notes

32. Pollination
• Cones produce seeds like
flowers ​(through pollination)
but Coniferous ​trees most
often produce two cones ​a
male and a female. Male
cones are smaller and
produce ​pollen they are on
the tree for less ​then a year.
Female cones produce ovules
and ​store the seeds. They stay
on the ​tree for much longer.
(the cones you ​see on the tree
in winter are female)

33. Reproduction Without Seeds
• There are three other ways
plants reproduce called:
Vegetative reproduction –
Reproduction of plants that
doesn’t involve seeds, plants
are identical
1. Runners - are long stems
that grow along the soil.

34. Reproduction Without Seeds
2. Rhizomes - are long stems that
grow underground.
3. Suckers - are new plants that
grow off the roots or stem of the
parent plant.

35. Reproduction Without Seeds
Cuttings - small pieces of a plant that usually
have a part of the stem and a few leaves
Grafting - attaching a part of one plant onto another
plant. The two sections eventually grow together

36. Reproduction Without Seeds

37. Plant Adaptations

38. Plant Adaptations
Plants have also changed over time.
Plants make changes to be better suited for their ​environment.
Adaptations are features that help an organism to survive and
be successful in their environment.
Physical/Structural - Example: Having wide leaves to gather
more sun.
Behavioral - The corpse flower releases chemicals when flies
have been inside it that triggers the opening of other corpse
flowers of the opposite sex.

39. Plant Adaptations
Why is a Cactus fat and round?
The water is quickly collected by
the roots and stored in thick,
expandable stems for the long
summer drought. The fleshy stems
of the barrel cactus are pleated like
an accordion and shrink as
moisture is used up. These pleats
also channel water to the base of
the plant during rain showers.

40. Plant Adaptations
Cactus Roots
Wide shallow roots - can catch
rain quickly
Deep and long roots - can
access underground water
supplies
(these often involve a tap root.

41. Plant Adaptations
Cactus Spikes
Prevent transpiration
Fend off predators
White dense spines help
reflect sunlight!

42. Plant Adaptations
Tropical Leaves
Grow tall to reach sunlight
Big leaves to get sunlight
Many tropical rainforest leaves have a
drip tip. It is thought that these drip tips
enable rain drops to run off quickly.
Plants need to shed water to avoid growth
of fungus and bacteria in the warm, wet
tropical rainforest.

43. Plant Adaptations
Different plants need different living condition and
have ​adapted to grow best in their environment under
these ​conditions.
Plants need the right amount of light, water,
nutrients ​and space. This is different for each kind of
plant but ​they all need all four. Seed plants also need to
be ​pollinated.

44. Role of Plants

45. Roles of Plants
What do you think is ​one of
the most ​important plants?
Phytoplankton! (a small
single celled plant that
accounts for over 50% of the
plant growth in ​the world
every year)

46. Roles of Plants
Plants are the key foundation to almost everything in ​our world!
Plants help to meet most of our needs.
1. They provide shelter for us and other animals.

47. Roles of Plants
2. They provide food for us and other animals.
Animals that don’t eat plants get their food from something
that at some time ate plants; so plants are the base of the
food pyramid.

48. Roles of Plants
3. Plants make their own food through photosynthesis
and the waste from photosynthesis is oxygen; everything
else would die without oxygen.

49. Roles of Plants
4. When a plant dies it rebuilds the soil, and helps new life begin.
The roots also help prevent erosion of soil.
Example: The rainforest. If an area of trees are removed in a few
years the soil is waste and can not grow things because there are
not enough nutrients in the soil (which come from the dead tree
leaves).

50. Roles of Plants
How do we use plants? Brainstorm ideas

51. Roles of Plants
5. Fibre: strong pieces of cell wall that plants use to ​connect cells
together. Only plants have cell walls and ​so only plants contain
fibre.

52. Roles of Plants
We have to ​manage living resources. If we use them to quickly we
could damage the ecosystem they naturally come from or we ​could
run out of them.

53. Soil

54. Soil
What is soil?
How is it different from dirt?

55. Soil
Soil is composed of different
types and sizes of particles.
It contains minerals, air, water
and ​organic matter, all of
which are needed for plants ​to
grow.

56. Soil
Minerals are from rocks
Organic matter is from organisms
(things that were living)
Humus is partly decomposed organic
matter. It ​provides the nutrients
plants need and also absorbs ​water.

57. Soil
There are different types of soil and each have different
characteristics. We will look at the characteristics of sandy
soil, loam soil and clay soil.

58. Soil
Sandy Soil:
• light brown
• has few lumps
• won’t stick together very well
• does not hold water very well
• it does not have much humus and so t
is not very good for growing plants.

59. Soil
Clay Soil:
• many colors (based on the minerals
it’s made of)
• has very small particle size
• feels slippery when wet but hard
when it is dry
• has a high mineral content but does
not have very much humus
• can hold water and nutrients but it is
hard for air to get into the soil

60. Soil
Loam Soil:
• is dark brown or black
• is good at holding moisture and air
• is a balance between organic
materials and minerals
• is the best soil to grow most plants

61. Changing the
Quality of Soil

62. Soil
• Soil is made of many things,
sand, clay, minerals, air, ​water
and organic matter (humus).
• Some soil is better then others.

63. Improve / Degrade Soil
• Human activities can improve or degrade soil.
• Improving: Makes soil better for plant growth.
• Degrading: Makes soil harder for plant growth.
• Plants naturally take nutrients from the soil.
Because ​we use plants for food and fibre we stop them
from ​rebuilding the soil naturally. As a result humans
must also do things to improve the soil to keep it
healthy.

64. Fertilizer
• Fertilizer: put nutrients back into the
soil.
• A bag of fertilizer often has three
numbers on it (like ​15 – 30 – 15)
• nitrogen – phosphorus – potassium
• It is often remembered as N-P-K which
are ​the symbols of the elements. The
higher each number is ​the more of each
fertilizer there is up to 100%.

65. Fertilizer
• Nitrogen helps keep the leaves
healthy, green and ​large.
• Phosphorus helps with both
the flowers and roots. ​Growers
often use a fertilizer high in
phosphorus to grow ​super
sized flowers.
• Potassium helps to grow large
fruits and vegetables.

66. Irrigation
• Irrigation: Watering the plants when
they need water helps keep ​them
strong and growing quickly.
• The problem some farmers face is
getting enough ​water and keeping
the lakes and rivers healthy at
the ​same time. The largest problem
with irrigation is using ​too much
water.

67. Clearing the Land
• Clearing the land: Before land can be
used for farming it must first
be ​cleared.
• Removing trees and other plants
makes it ​easier for the crop to get a
good start and grow strong.
• Farmers use tools like ​plows and
seed drills to ​keep air in the soil,
remove ​unwanted plants, plant ​seeds
below old crop ​stubble and prevent
wind ​erosion.

68. Clearing the Land
• Clearing land has advantages and
disadvantages:
• adv - more food, easier to row a
specific crop
• dis - allows erosion to occur more
easily, destroys ecosystems.

69. Crop Rotation
• Crop Rotation: different crops in
different fields at different times
of ​the year.
• This helps the fields because different
plants ​need different nutrients and
one nutrient is not ​completely stripped
from the field.
• One plant uses the ​nutrients the other
plant ​doesn’t need. Because of ​this the
farmer can use ​much less fertilizer.

70. Crop Yields

71. Crop Yields
Investigation Time!
Answer the questions on the handout using the textbook pages.

72. Crop Yields
• Crop Yields: The amount of useful plant
material produced per plant or area
1. Pesticides – Kill insects
2. Fertilizer – Improves nutrients
3. Watering - Irrigation
4. Greenhouse – Provides the perfect
environment for plants to grow.

73. Crop Yields
• Greenhouses:
o Plants in a greenhouse always have the right temperature, light,
and nutrients for their needs.
• Hydroponics:
o is another type of artificial soil environment.
o plants are grown without soil.
o the roots of the plants are buried in gravel or coarse sand.
o Nutrient-rich water is then pumped through this material at
regular intervals.

74. Selective Breeding

75. Selective Breeding
Investigation Time!
Answer the questions on the handout using the textbook pages.

76. Selective Breeding
• Species: a group of organisms with similar traits that can
reproduce successfully. Ex. sunflowers
• Variety: a subset of a species. Ex. granny smith apple vs.
royal gala apple
• Trait: a desirable characteristic of a species. Ex. seedless
vs. non-seedless watermelon

77. Selective Breeding
• Selective Breeding: When humans choose to breed an
organism with desirable traits. Example: trying to breed
roses with the largest flower.
• Genetic Engineering: is a process in which single genes
are added to a plant’s cells.
• Genes: tiny piece of material in a cell’s nucleus. Each
gene in a cell is responsible for the inheritance of certain
traits or characteristics.

78. Selective Breeding

79. Selective Breeding
• Problems associated with a new plant:
o It can attract pests so pesticide is needed
o More fertilizer & water needed
o Expensive
o Cross-pollination creating resistant super weeds

80. Selective Breeding

81. Controlling Weeds

82. Controlling Weeds
• Insects eat a lot of food. For some insects their food is ​plants
and the easiest plants for insects to find are often ​the same
plants we grow for our food.
• How do we stop these unwanted insects… with ​pesticides.

83. Controlling Weeds
• The problem is pesticides also kill other animals that we ​may
not want to harm or can bioaccumulate in the food chain.
• This is an unintended consequence of human involvement in
changing natural environments.

84. Controlling Weeds
• Not all problems are insects or even
animals. Other ​plants also find the soil
in farmers fields to be great ​places to
grow.
• The fields have removed the
competition, and have ​great soil, often
are fertilized and irrigated and
because ​of all these good things weeds
can be a large problem ​for crops.
• Farmers use herbicides to control some
of the unwanted plants but they cannot
kill all unwanted ​plants.

85. Controlling Weeds
• Again there are problems with the
uses of ​herbicides. Some plants grow
resistant to them, they ​degrade the
soil and they cost the farmer
more ​money.

86. Controlling Weeds
• So what is one of the better sources
pest control?
• Biological control is the use of
natural predators to control insects.
• For example ladybugs eat
aphids, ​which are problems for
Tomato growers.