Plant Reproduction

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Chapter 8 Plant Reproduction and
Response Section 1 Seedless Plants (Ferns,
Horsetails Club Mosses)
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Ferns
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Ferns ?Characteristics 1. most common type of
seedless plant -reproduce with
spores -need a moist environment 2. have
stems (rhizomes), roots and leaves (fronds)
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3. do not have very well developed
xylem and phloem
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?Life Cycle 1. a ferns life cycle is made
of 2 stages or generations 2. one
stage is asexual, the other is sexual
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alternation of generations a reproductive
process with BOTH sexual AND asexual phases
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?Stage 1 ASEXUAL phase - SPOROPHYTE

GENERATION -during this phase, the plant
produces spores that can be seen on the
bottom of the leaves -the spores develop into
the gametophyte (next stage)
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?Stage 2 SEXUAL phase- GAMETOPHYTE

GENERATION -the same plant (gametophyte)
produces both male AND female sex cells
or gametes -male gamete (sex cell) sperm
-female gamete (sex cell)egg
?Stage 1 ASEXUAL phase - SPOROPHYTE
GENERATION -during this phase, the plant
produces spores -the spores can be seen on
the bottom of the leaves -the spores develop
into the next stage
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2. Stages 1) A spore is released
(sporehaploid 1n) 2) The spore develops into
a gametophyte
(gametophytehaploid 1n)
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3) The gametophyte releases BOTH male AND
female gametes 4) The gametes (egg sperm)
fertilize one another
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5) The fertilized gametes (called a
zygote) develop into a
sporophyte (diploid2n) that
grows off the original gametophyte
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6) The sporophyte grows and releases more
spores (sporehaploid 1n) 7) The cycle
starts again!
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?1nhaploid (1 set of chromosomes) -sperm cells
and egg cells each have only 1 set of
chromosomes ex humans egg cell has 23
chromosomes sperm cell has 23 chromosomes
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?2ndiploid (2 sets of
chromosomes) -when
fertilization occurs (sperm egg unite), the
new cell will have a full set of
chromosomes
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ex In humans, when an egg cell (23
chromosomes) is fertilized by sperm cell (23
chromosomes), the resulting zygote then has 46
chromosomes (23 23 46
chromosomes) egg sperm 46
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?sporangia a single case that holds spores
on the bottom of a fern leaf ?sori
groups of brown dot-like spore cases
on the bottom of fern leaves
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sori
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sori
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?rhizoids root-like structures that grow from
a gametophyte into the ground to anchor the
plant and supply it with minerals and water

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?gametophyte the stage of a plants life
cycle when both male and female sex cells or
gametes are produced ?gametes sex cells
produced by the male and female organs male
gamete ? sperm female gamete? egg
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?zygote a fertilized egg produced by
the joining of a sperm and an egg
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