Lesson 9: Sexual Reproduction in Flowering Plants
Station 1: Perfect Flower Drawing1. Draw a DETAILED picture of the parts of a perfect flower.
2. Use page 108 or the diagram at the station to help you label all the parts.
Name of Plant: ____Alstroemeria
(tiger lily)________________________
Station 2: Imperfect Flower Drawing1. Draw a DETAILED picture of the parts of a perfect flower.
2. Use page 108 or the diagram at the station to help you label all the parts.
.
Name of Plant: _____Daisy (or, chrysanthemum) ________________________
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Station 3: Pollen Drawing
1. What do you notice about the shape of the
pollen?
The pollen is oval with a small
trough (groove) in the middle, and
has a rough texture.
2. Why do you think this is beneficial to the
pollen?
Allows for aerodynamic flight
through the air; sticks to animals
that can carry it to the stigma.
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Station 4: Ovary Drawing
1. What do you notice about the features of the
ovary?
There are three chambers,
surrounded by a thick outer wall.
2.
Why do you think this is beneficial to the
ovary?
It holds and protects the ovules
(unfertilized seeds) for release.
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The Wonder of Flowering Plants (OMM p. 116-119 )
1. What type of an organ is a flower to a plant?
Flowers are the reproductive organs of certain plants.
2. What is the male reproductive structure on a plant?
Stamen are the male reproductive structures of flowering plants.
a. What parts make up this structure and what do they do?
The top of the stamen is the anther (produces pollen)
The tall pipe-like part is the filament (supports the anther)
3. What is the female reproductive structure on a plant?
The pistil is the female reproductive structure of flowering plants.
a. What parts make up this structure and what do they do?
Stigma: Contains sticky substances so that the pollen can be
collected.
Style: tube-like structure that carries the pollen nuclei down to the
ovary.
Ovary: Contains the eggs.
4. What is the difference between a "perfect" and an "imperfect"
flower?
Perfect flowers contain both male and female reproductive
Organs; imperfect flowers have either one or the other.
(The other reproductive part is on another plant or flower).
5. What is pollination?
Pollination is when the pollen from an anther lands on the stigma.
6. What are the two types of pollination
The two types of pollination are: self-pollination, and crosspollination
a. How do they differ?
Self-pollination happens on the same plant
Cross-pollination happens on different plants
7. How do plants get pollen? Explain the method for each type of
pollination.
Self-pollination can happen by wind, shaking of the plant, gravity,
or a raindrop. Cross-pollination can happen by animals, bees, etc.
Pollen attaches to the animal, and is transferred to another flower.
NOTE: SELF POLLINATION CANNOT HAPPEN ON AN IMPERFECT
FLOWER.
8. What is fertilization?
When the sperm nucleus (pollen) meets the egg nucleus (ovule).
9. How is the endosperm produced?
The endosperm is produced when another sperm nucleus fuses with
the already fertilized egg.
10.
What part of the original flower eventually becomes a fruit?
The ovary matures to become the fruit.
a. What is the function of the fruit?
The function of fruit it to protect and disperse seeds.
11.
Why do flowers need to adapt in order to enhance pollination?
Flowers adapt to be more efficient at pollination, fertilization and
seed production.
12.
How are flowers adapted to encourage pollination?
Flowers are adapted to attract attention so as to encourage
pollination.
Lesson 9 Reflecting
1. Using “The Wonder of Flowering Plants” as a reference, explain
what happens inside the flower after pollination.
AFTER POLLINATION:
a) A tube grows from the pollen grain down to the ovary.
b) Sperm nuclei move down the tube and one unites with the egg
nucleus of an ovule in a process called fertilization.
c) This process begins the formation of a seed.
2. What do you think will develop as the flowers wither? Hint: Think
about the name of the structure that protects the seeds.
As the flower withers, fruit develops, which protects and helps the
dispersal of the seeds.
3. Why do you think some flowers have so many pollen grains and
ovules?
Lots of pollen and ovules makes sure that fertilization can take place, and
that lots of seeds are produced to continue the species.