Slide 1
Structure
of
Plants
&
Reproduction
What do plants need to grow?
Space
Temperature
Sunlight
Water
Nutrients (N, P, K)
Air (CO2)
Time
Plants
1. Photosynthesis – process that provides
energy for almost all life occurs in
chloroplasts. Know the chemical equation.
6CO2
+ 6H2O
Carbon dioxide + Water
Light
C6H12O6 + 6O2
Glucose Oxygen
Plants
2. Chloroplasts – organelles that use light
energy to make carbohydrates from
carbon dioxide and water through the
process of photosynthesis.
Plants
3. Cell wall – surrounds plant cell provides
support and protects from damage made of
protein and carbohydrates, like cellulose.
Plants
4. Central vacuole – stores water and may contain
ions, nutrients, and wastes. Makes the plant
cell rigid and stand upright. (page 66)
Plants
5. Glucose – a single sugar (monosaccharide)
made through photosynthesis
light
6CO2
+ 6H2O
C6H12O6 + 6O2
Carbon dioxide + Water
Glucose Oxygen
Kinds of Plants
Nonvascular Plants
– Small
– Lack vascular tissue
– Examples = moss,
liverworts and hornworts
• t
Moss
Liverworts
Vascular Plants
– Has tissue that moves food
and nutrients around plant
– leaves, stems, and roots
– produces food for plant
only in leaves
Plant Tissue Systems
•3 types of plant tissues
1) Dermal tissue
2) Vascular tissue
3) Ground tissue
Dermal tissue
•Epidermis
– Single layer of cells that make
up outer covering of plants
•Cuticle
– Thick, waxy coating that
protects against water loss and
injury
– Found on most fruits, stems &
leaves
Cuticle and Stoma
Cuticle Cross Section
Stoma
Vascular Tissue
• Transport system; moves water &
nutrients throughout plant
– Xylem
•Carries water upward from roots to
plant structures
– Phloem
•Transports nutrients &
carbohydrates produced by
photosynthesis
Plants
Xylem – vascular tissue of plants that
transport water and minerals.
Xylem zips up!
Plants
Phloem – vascular tissue of plants that
transport organic nutrients.
Phloem =
food down.
Plants
Stomata – (singular stoma) pores that
exchange oxygen and carbon dioxide.
Closed
Plants
Guard cells – specialized cells that border
stoma. Closes & opens pores for gas
exchange.
Ground Tissue
•Cells between dermal and
vascular tissues
•3 types of cells make up
ground tissue
1) Parenchyma cells
2) Collenchyma cells
3) Sclerenchyma cells
Plant Structure
•Major organ systems
•Roots
•Stems
•Leaves
Plants
Shoot (stem) – structure that grows upward.
Shoot also
called the stem
1. Supports plant
2. Holds leaves/ branches upright
3. Houses transport system that carries
water & nutrients through tissues
Plants
Root – structure that grows downward.
Root
Roots
1.
2.
3.
Anchor & support
Absorbs water &
minerals through
tissues
Hold soil in place
Root Hairs
Fibrous Roots
Functions of Leaves
1. Photosynthesis
2. Broad, flat surface increases
surface area for light absorption
3. Have systems to prevent water
loss
• Stomata
• cuticle on surface
4. Gas exchange
• Allow CO2 in and O2 out of
leaf
Elephant Ear Plant
Transpiration
1.
Transpiration: loss
of excess water from plant leaves
2. Significance:
a. Transpiration causes enough
pressure to help pull water
(& required nutrients) up
stem from roots.
b. As part of the water cycle,
trees transpire water back into
the atmosphere.
c. Transpiration provides much
of the daily rain in rainforest.
A
B
A average size maple tree can
transpire 200 liters of water per
hour during the summer.
Transpiration is the #1 driving
force for pulling water up stems
from roots.
Kinds of Plants
Gymnosperms
Angiosperms
– Seed plants that produce
cones
– Ex. Pine trees, giant sequias,
douglas firs, and ginkgo tree
– Seed plants that produce
fruit and flowers.
– Ex. Sunflowers, apple trees,
and grass
Sunflowers
Spores on the
underside of fern
leaves.
Grass
The unique fan-like
leaves of the ginkgo
tree
Angiosperms – 2 Types
1. Monocot
– Produces seeds with
one seed leaf
(cotyledon)
2. Dicot
– Produces seeds with
two seed leaves
(cotyledon)
Plant
Reproduction
Plants
Vegetative propagation – asexual reproduction of
plants from a modified stem, root, or leaf.
Plants
Pollination – transfer of male reproductive
structures (pollen) of a plant to the female
reproductive structures (ovules) of a plant.
• Fertilization:
union of male
and female
gametes to
form a zygote.
Plants
16. Germination – seed breaks from dormancy
(inactivity) and embryo resumes development.
Life Cycle of a
Gymnosperm
 Tree produces male
and female cones.
 Male pollen scattered
by wind and fertilizes
female ovule when
trapped by sticky
substance.
 Wind disperses pine
seeds
 Seed grows into
seedling  tree
Life Cycle of an
Angiosperm
• Pollen grains
produced by
anther land on
stigma
• Pollen tube grows
into ovule
• Sperm cell moves
through tube and
fertilizes the egg.
• Ovule develops
into seed with the
seed’s embryo
inside.
• The ovary
develops into a
fruit.
• Seeds are
dispersed and
grow into a new
plant.
What is the purpose of
flowers for plants?
A. Function of a Flower
1. Attract pollinators2. Site of sexual
such as insects,
reproduction
birds, and bats
3. Forms fruit that
o Brightly colored will carry seeds
(embryos)
o Fragrant
o Produce nectar
Slide # 12
B. Structure of a Flower
1.Pistil: female
reproductive structure
a. Stigma: sticky tip; traps
pollen
b.Style: slender tube;
transports pollen from
stigma to ovary
c. Ovary: contains ovules;
ovary develops into fruit
d.Ovule: egg; develops
into seed when fertilized
Slide # 13
Female Reproductive Leaf
B. Structure of a Flower
2.Stamen: male
reproductive structure
a.Anther: knob-like
structure; produces
pollen
b.Filament: thin stalk;
supports anther
c.Pollen: contains
microscopic cells
that become sperm
cells
Slide # 15
Male Reproductive Leaf
Contains Pollen
B. Structure of a Flower
3.Sepal: encloses &
protects flower
before blooms
(sepals=calyx)
4.Petals: usually
colorful & scented;
attracts pollinators
Slide # 17
C. Cross Pollination
• How does pollination happen?
– Pollen from different anther
fertilizes ovary on another
flower.
• What is the result of pollination?
• A Fruit: An ovary containing
seeds.
• Seed - protect embryo from
damage and water loss;
dispersed away from parent
plant
E. Types of Seed dispersal
What is seed dispersal?
 Method for seeds to spread away
for parents.
Why is seed dispersal important?
• Reduces competition (parents)
• Increases chance for survival
Seed Dispersal
• Wind
– Flight
• Water
– Flotation
• Animal
– Fruits
– Burrs
Can you
identify the
type of seed
dispersal that
may be used by
these plants?
WIND
WATER
WIND
Flower Dissection Lab
• Groups of 4
• Have one person in group get materials.
• Each person will do worksheet.
• Read directions on lab procedure.
• If have questions, make sure answer is
not in lab procedures or other group
members do not know before asking
teacher.
• Look at Ch. 23 and 24 for reference.
– Pg 538