Chapter 24 - Jamestown Public Schools

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Transcript Chapter 24 - Jamestown Public Schools

Exploring Plants
Plant Reproduction
Plant Reproduction
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Reproductive Structure of
Seed Plants
 Male sex cells  pollen grain – has thick
protective wall
 Ovule  female sex cells of a seed plant
 Pollination  transfer of pollen grains
from male reproductive structures to
female reproductive structure
Reproductive Structure of
Seed Plants
 Pollen tube  grows from pollen grain to
ovule, allowing sperm to pass directly to
an egg
Seeds
 Hard, outer cell layers of ovule  seed
coat - protects the embryo
 Cotyledon  seed leaves, part of plant
embryo- transfer nutrients to embryo
Cones
 Sex cells of gymnosperms develop in
cones
 Male cones produce pollen grains,
female cones produce ovules
 Pollen carried by wind
 Seed cones close up after pollination, &
remain closed until seed is mature
Flowers
 In angiosperms, sex cells
(gametophytes) develop in flowers
 Sepal  protects the flower from
damage while in the bud
 Petal  attracts pollinators (very pretty)
 Stamens  produce pollen
 Anther  top of stamen, pollenproducing sac
Flowers
 Pistil  produces ovules
 Ovary  swollen, lower portion of pistil
 Complete flowers have all 4 parts
Flowers
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Flowers & Pollinators
 Flowers have bright colored petals, sugary
nectar, strong odors, & different shapes to
attract animal pollinators
 Flowers are source of food for insects, birds,
and bats.
Pollination & Fertilization
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Vegetative Reproduction
 Asexual reproduction that involves nonreproductive parts: stems, roots, & leaves
 Many structures are modified stems 
runners, bulbs, corms, rhizomes, & tubers
 Vegetative reproduction is faster than sexual
reproduction
 Examples: spider plants, onions, ferns, potato
Examples of Stems Modified for
Vegetative Reproduction
Plant Propagation
 Growing new plants from seed or from
vegetative parts
 Ex: budding,
grafting, cuttings,
cultures