Seedless Plants

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Seedless Plants
Nonvascular Seedless Plants
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Mosses, liverworts, hornworts
Grow on soil, bark of trees, rocks
Usually live in places that are damp
Are very small
Each cell of the plant must get water from the
environment
• Some have a rhizoid, a rootlike structure that
helps the plant hold itself in place
Seedless Vascular Plants
• Ferns, horsetails, club mosses
• These plants have vascular tissues that
specialize in moving nutrients around the
plant
• Some of these plants have a rhizome, an
underground stem from which new leaves and
roots grow
Life cycle of Seedless Plants
• Sporophytes release spores into air
• Spores grow into male and female
gametophytes
• Sperm from male plants swims through water
to fertilize eggs
• Eggs grow into sporophyte and the process
repeats
• Water is necessary in the lifecycle of this type
of plant
Seed Plants
• The two groups of vascular seed plants are the
gymnosperms and the angiosperms
• Gymnosperms do not have flowers or fruit
• Angiosperms have flowers and seeds that are
protected by fruit
Characteristics of Seed Plants
• Produce seeds. Seeds nourish and protect young
sporophytes
• Gametophytes and sporophytes do not live
independently of each other. Gametophytes
from within the reproductive structures of the
sporophyte
• Sperm from seed plants is protected and forms
inside pollen. Pollen can be carried by animals or
the wind
• Seed plants can live just about anywhere and are
the most common plants on Earth today
Structure of Seeds
• Seeds form after fertilization
• Seed has three parts, sporophyte, stored food
or cotyledons, seed coat that surrounds and
protects young plant
Gymnosperms Life Cycle
• Evergreens or cone bearing plants and trees
• Seed contains a young sporophyte which grows
into an adult sporophyte
• Spores are produced and they grow into
gametophytes
• Females gametophytes produced eggs and male
gametophytes produce sperm in pollen
• Wind or insects carry pollen to eggs.
• Fertilized egg develop into a seed that contains a
sporophyte
Angiosperms
• Vascular flowering plants that produce flowers
and fruit
• Angiosperms use flowers and fruit to attract
insects and animals to help spread pollen to
eggs
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