Download Gymnosperms

5/4/2011
What events occur in the xylem and
phloem?
xylem- water and minerals move upward
phloem- food moves to other parts of the plant
Chapter 5
Section 2
What is the most important thing a seed
needs to germinate?
water
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1. Identify the characteristics of
gymnosperms.
2. Describe how gymnosperms reproduce
Characteristics
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Cycads- look like palm trees with cones.
Grow in tropical areas
Conifers- cone-bearing plants. Most diverse
group. “evergreens”
Ginkgoes- only one species Ginkgo biloba.
Gnetophytes- trees, shrubs or vines. Grow in
deserts and tropical rain forests
A seed plant that
produces naked
seeds (not enclosed
by protective fruit)
Many have needlelike or scale like
leaves
Many have deep
growing root
systems
What are the 4 groups of gymnosperms?
Cycads, conifers, ginkgoes, gnetophytes
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Terms:
Steps:
Cone- reproductive structure covered with
scales (male and female)
Pollen (male)- contain cells that will become
sperm
Ovule (female)- contains an egg cell
1.
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The transfer of pollen from a male
reproductive structure to a female
reproductive structure
Pollen collects in the ovule
Pollen is usually carried by the wind
Female cones remain on tree until seeds
mature
Male cones fall off
2.
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4.
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Pollination
Fertilization
Seed development
Seed dispersal
After pollination, the ovule closes and seals
in the pollen
Scales close
Sperm cell fertilizes the egg cell
Egg develops into the embryo part of the
seed
Scales open when seeds are mature
Wind shakes the seeds out of the cones
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What is the reproductive structure of
most gymnosperms called?
Cone
What is pollination?
Transfer of pollen from male to female
structures
First, pollen falls
from a male cone
onto a female
cone. In time, a
sperm cell and an
egg cell join
together in an
ovule on the
female cone.
After fertilization
occurs, the seed
develops on the
scale of the
female cone.
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