Download How plants reproduce

How plants reproduce
By Ekaterina Zhdanova-Redman
Spring is a wonderful time of a year. Flowers are
everywhere. Blooming trees, bushes, and plants are
beautiful. The air is filled with their sweet fragrances.
Bees and butterflies are flying from one bright flower
to another. Why do they do that?
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You know, of course, that bees produce honey.
They make it from nectar they gather from flowers.
Nectar is a sweet and viscous liquid. It is located in
plants' blossoms, leaves, and stems. Different living
things use nectar as their food--bees, wasps, butterflies, moths, even some
birds and mammals! But they are not the only ones who benefit from it.
Nectar-eating insects and birds also help flowering plants reproduce.
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You may have observed tiny yellow grains inside some flowers. This is
called pollen and it is used by flowers to form seeds. Plants make the pollen
in the saclike anthers of their flowers. The anthers are part of the stamen--the
male part of reproduction. The female part is called the pistil, and it includes
the stigma and the ovary. The stigma receives the pollen and leads it to the
ovary--the egg-bearing part of the plant. The process of moving pollen from
anthers to stigma is called pollination.
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When pollen reaches the egg cell inside the ovary, it causes the cell to
divide. Each cell then becomes a seed embryo and develops into the seed.
This process is called fertilization. Because of fertilization, seeds have
characteristics of both male and female cells. Some plants have both pistils
and stamens on their flowers. They are perfect flowers. They can transfer
pollen from their own anthers to their own stigmas. This process is called
self-pollination.
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It is necessary for self-pollinating flowers to prevent other plants' pollen
from getting into their stigmas. This is why in some flowers the pollination
occurs before the blossom opens. Some other flowers are so constructed that
pollen from other blossoms simply can't enter them. Look at the flowers of
beans, peas, or snapdragons. They grow a kind of a trap door for protection
against other pollens. You may also notice that these flowers have no scent.
Can you tell why?
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But not all flowers are perfect. Some of them have only pistils and are
considered female flowers. Others have only stamens, which makes them
male flowers. These kinds of flowers are called cross-pollinating. They must
depend on wind, insects, birds, or other means to carry their pollen from
male flowers to female ones. This is why they have showy blossoms, a
fragrant scent, and sweet nectar, all of which attract various insects and
birds. They fly from flower to flower and transport sticky pollen on their feet
and bodies.
The type of reproduction you just learned about is called sexual. It
requires female and male parts of plants to reproduce. Some plants have
either male flowers or female flowers. Did you know that some plants have
both male and female flowers on the same plant? Some plants even have all
three kinds of flowers on the same plant--male, female, and perfect ones!
The plants that have female, male, and perfect flowers on the same plant are
called polygamous.
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If some plants do not have flowers, seeds, or fruit, how do they
reproduce? Some plants have special parts that produce tiny one-celled
structures called spores. Each spore either alone or combined with another
spore produces a new plant. The production of plants by means of spores
that do not have male or female parts is called asexual (nonsexual)
reproduction.
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Another type of asexual reproduction is called vegetative. Instead of
involving flowers and seeds, other parts of plants are used for reproduction.
Potatoes, for example, will grow from pieces cut from them and planted.
Other plants, like strawberries, send out trailing ground stew, which take
root to produce new plants. Plants can reproduce from roots, slips, or leaves.
In all those cases a new plant will be just like the old one.
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Gardeners also have learned that a plant may grow from a slip attached
to a stem of a different kind of plant. This process is called grafting. You
may have seen an apple tree in which different branches grow different
kinds of apples. A single apple tree once bore thirty different kinds of
apples!
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Copyright © 2015 edHelper
Name
_____________________________
How plants reproduce
Date
___________________
1. Insects flying from flower to
flower gather _____.
Honey
Seeds
Nectar
Pollen
3. Pollen is used to form _____.
Seeds
Flowers
Fruit
Leaves
5. Pistils are a _____ part of
reproduction.
Male
Female
Neutral
None of the above
7. Perfect flowers have _____.
Both pistil and stamen
Only pistils
Only stamens
None of the above
2. Nectar is located in _____.
Flowers, leaves, and stems
Roots
Seeds
Fruit
4. Stamens are a _____ part of
reproduction.
Male
Female
Neutral
None of the above
6. The process of moving pollen is
called _____.
Cross-pollination
Pollination
Reproduction
Self-pollination
8. The process of growing a new
plant from a slip attached to a
stem of a different plant is called
_____.