Plant Reproduction and
Development
Plants are among
the most successful
organisms on the
planet. Their
success can be
attributed to various
biological
adaptations that let
them thrive many
habitats. 2
The ability of
plants to alter
between
reproduction and
development
allowed to
colonize
environments
with diverse
conditions.
3
Plants have also
evolved various
reproductive
structures to Magnolia flower Fern spores
allow them to
increase their
chances of
successful
fertilization and
development.
Gymnosperm cones Passionfruit flower
4
How does the life cycle of a plant
begin?
5
Review of Plant Characteristics
Life cycle with
Multicellular Cellulosic
alternation of
organisms cell wall generations
Photosynthetic Plastids in
capacity cytoplasm
6
Review of Major Plant Groups
Hornworts
Land
Plants
Non-Vascular
Plants
lignified vascular
tissues absent
Liverworts
Mosses
} spore-bearing
non-vascular
spore-bearing
plants
vascular plants
Pteridophytes
Vascular
Plants Gymnosperms
Spermatophyte cone-bearing
lignified vascular plants
tissues present s
seed-bearing Angiosperms
vascular plants
flowering plants7
Review of Major Plant Groups
Bryophytes (Spore-bearing non-vascular
plants)
Hornworts Liverworts Mosses
8
Review of Major Plant Groups
Pteridophytes (Spore-bearing vascular
plants)
Ferns Horsetails Lycophytes
9
Review of Major Plant Groups
Spermatophytes (Seed-bearing vascular
plants)
Gymnosperms Angiosperms Angiosperms
(Monocot) (Dicot)
10
Alternation of Generations
Common life cycle pattern for
green plants
Alternation of haploid and
diploid phases
Sporophyte is the diploid stage,
while gametophyte is haploid
Meiosis forms haploid spores,
mitosis forms haploid gametes
Diploid chromosome number is
restored through fertilization
11
Floral Anatomy
The pistil
consists of
the female
structures in
flowers (i.e.,
stigma,
style, ovary)
12
Floral Anatomy
The stigma
is a
structure
where the
pollen
grains must
land during
pollination.
13
Floral Anatomy
Style is the
stalk of the
stigma that
leads to the
ovary.
Within it is
the pollen
tube.
14
Floral Anatomy
Ovary is the
female
structure in
flowers that
house the
female
gametes.
15
Floral Anatomy
Ovules are
small
structures
within the
ovary. Each
of them
contains an
egg nucleus.
16
Floral Anatomy
Stamen
refers to the
male portion
of the
flower. It
consists of
anthers and
filaments.
17
Floral Anatomy
Anther is the
male
structure
that
produces
and stores
the pollen
grains.
18
Floral Anatomy
Filament is
the staminal
structure
that serves
as the stalk
of the
anther.
19
Floral Anatomy
Petals are
the colorful
leaf-life
structures in
flowers that
primarily
attract
pollinators.
20
Floral Anatomy
Sepals are
green leaf-
like
structures
that protect
the
structures in
a flower
bud.
21
Floral Anatomy
Receptacle
is the
thickened
portion
below the
ovary where
floral
structures
grow.
22
Floral Anatomy
Pedicel is
the stalk of
the flower
which
provides
support to
all floral
parts.
23
Angiosperm Life Cycle
The seeds inside a fruit
contain the developing
embryos. It is the first
sporophyte stage.
24
Angiosperm Life Cycle
The embryos
undergo
development and
differentiation to
become seedlings.
The seeds inside a fruit
contain the developing
embryos. It is the first
sporophyte stage.
25
Angiosperm Life Cycle
Continuous growth and
development allows a
seedling to reach
maturity.
The embryos
undergo
development and
differentiation to
become seedlings.
The seeds inside a fruit
contain the developing
embryos. It is the first
sporophyte stage.
26
Angiosperm Life Cycle
Continuous growth and The adult stage becomes
development allows a sexually mature.
seedling to reach
maturity.
The embryos
undergo
development and
differentiation to
become seedlings.
The seeds inside a fruit
contain the developing
embryos. It is the first
sporophyte stage.
27
Angiosperm Life Cycle
Continuous growth and The adult stage becomes
development allows a sexually mature.
seedling to reach
maturity.
The embryos
undergo
development and The adults now
differentiation to produce gametophytes
become seedlings. in pollens and ovules.
The seeds inside a fruit
contain the developing
embryos. It is the first
sporophyte stage.
28
Angiosperm Life Cycle
Continuous growth and The adult stage becomes
development allows a sexually mature.
seedling to reach
maturity.
The embryos
undergo
development and The adults now
differentiation to produce gametophytes
become seedlings. in pollens and ovules.
The seeds inside a fruit
contain the developing Fusion of the gametes
embryos. It is the first occurs during
sporophyte stage. pollination.
29
Angiosperm Life Cycle
Continuous growth and The adult stage becomes
development allows a sexually mature.
seedling to reach
maturity.
The embryos
undergo
development and The adults now
differentiation to produce gametophytes
become seedlings. in pollens and ovules.
Thereafter, the ovary
develops into a fruit.
The ovules become
seeds.
The seeds inside a fruit
contain the developing Fusion of the gametes
embryos. It is the first occurs during
sporophyte stage. pollination.
30
Gymnosperm Life Cycle
Female Cones Male Cones
31
Gymnosperm Life Cycle
Embryos develop into
seedlings and into
mature sporophyte.
32
Gymnosperm Life Cycle
Upon reaching
sexual maturity,
gametophytes are
produced in the
male and female
cones.
Embryos develop into
seedlings and into
mature sporophyte.
33
Gymnosperm Life Cycle
Upon reaching
sexual maturity,
gametophytes are
produced in the The pollens from the
male and female male cones pollinate the
cones. ovules in female cones.
Embryos develop into
seedlings and into
mature sporophyte.
34
Gymnosperm Life Cycle
Upon reaching
sexual maturity,
gametophytes are
produced in the The pollens from the
male and female male cones pollinate the
cones. ovules in female cones.
Fertilization
occurs,
which
Embryos develop into
seedlings and into
transforms
mature sporophyte. ovules into
seeds. 35
Fern Life Cycle
Spores at the underside of fertile A heart-shaped, free-living
fronds (sporophyte) of a fern species gametophyte of a fern species 36
Fern Life Cycle
The young
sporophyte
develops into
mature ferns.
37
Fern Life Cycle
Fertile ferns
produce
spores
through
meiotic
division.
The young
sporophyte
develops into
mature ferns.
38
Fern Life Cycle
Fertile ferns
The spores from
produce
the sporangium
spores
develop into
through
gametophytes.
meiotic
division.
The young
sporophyte
develops into
mature ferns.
39
Fern Life Cycle
Fertile ferns
The spores from
produce
the sporangium
spores
develop into
through
gametophytes.
meiotic
division.
The mature
gametophyte
produces
eggs and
sperms.
The young
sporophyte
develops into
mature ferns.
40
Fern Life Cycle
Fertile ferns
The spores from
produce
the sporangium
spores
develop into
through
gametophytes.
meiotic
division.
The mature
gametophyte
produces
eggs and
sperms.
The young Fertilization
sporophyte occurs, which
develops into forms the
mature ferns. zygote.
41
Fern Life Cycle
Fertile ferns
The spores from
produce
the sporangium
spores
develop into
through
gametophytes.
meiotic
division.
The mature
gametophyte
produces
The diploid eggs and
zygote sperms.
develops into
a young
The young sporophyte. Fertilization
sporophyte occurs, which
develops into forms the
mature ferns. zygote.
42
Comparison of Reproductive Structures and
Processes
Structures and Pteridophytes and
Angiosperm Gymnosperm
Processes Bryophytes
Floral Structures Present Absent Absent
Cones Absent Present Absent
Primary Dispersal
Seeds Seeds Spores
Structures
Pollination Present Present Absent
Fruit Formation Present Present Absent
Some sporophyte,
Dominant Stage Sporophyte Sporophyte
some gametophyte
43
Forms of Reproduction in Angiosperms
Asexual Reproduction Sexual Reproduction
44
Forms of Reproduction in Angiosperms
Asexual Reproduction Sexual Reproduction
May either involve single (self-
Requires a single or lone parent
pollination) or two parents
(cross-pollination)
45
Forms of Reproduction in Angiosperms
Asexual Reproduction Sexual Reproduction
May either involve single (self-
Requires a single or lone parent
pollination) or two parents
(cross-pollination)
Does not involve the fusion of Requires the fusion of a sperm
gametes cell and egg cell during
fertilization
46
Forms of Reproduction in Angiosperms
Asexual Reproduction Sexual Reproduction
May either involve single (self-
Requires a single or lone parent
pollination) or two parents
(cross-pollination)
Does not involve the fusion of Requires the fusion of a sperm
gametes cell and egg cell during
fertilization
Offspring are genetically Enhances genetic variation
identical to the parent organism because the parents and
offspring are not genetically
identical 47
Asexual Reproduction: Apomixis
Floral units/flowers Mature fruits and
seeds
Apomixis in some species of dandelions allows the production
of embryos from unfertilized eggs in ovules. 48
Asexual Reproduction: Apomixis
Apomixis is a genetic feature in dandelions, which therefore, allows them to
produce viable seeds without undergoing pollination. 49
Asexual Reproduction: Vegetative
Propagation
Vegetative propagation allows plant parts to produce buds that
can develop into new individuals. 50
Asexual Reproduction: Vegetative
Propagation
Stolon Stolon Stolon
Main Plant Buds Bud
Strawberries (Fragaria sp.) performs vegetative propagation
through the buds that emerge from stolons or runners. 51
Sexual Reproduction: Pollen Grains
Pollen grains contain the male
gametophytes in angiosperms.
Each pollen grain consists of two
sperm nuclei from the generative
nucleus.
The tube nucleus will transport the
sperm during pollination.
52
Sexual Reproduction: Ovules
Each ovule or embryo sac in the
ovary of the flower consist of eight
nuclei.
The primary sex cell that is
fertilized is the egg nucleus or egg
cell.
Only the polar nuclei and egg
nucleus will have descendant in
seeds.
53
Sexual Reproduction: Double Fertilization
Pollen grains land on the stigma of the
pistil. The pollen tube extends itself.
The pollen tube moves down the style
towards alongside two sperm nuclei.
In the embryo sac, one of the sperm
nuclei fertilizes the egg nucleus to
form embryo.
The other sperm nucleus fertilizes the
polar nuclei to produce endosperm.
Double fertilization produces a diploid
embryo and a triploid endosperm.
54
Sexual Reproduction: Double Fertilization
The fate of the sperm nuclei, egg nucleus, and polar nuclei
during double fertilization in angiosperms 55
Plant Development
The shoot apical meristem
allows the continuous
upward growth of the plant.
56
Plant Developmenta
The shoot apical meristem
allows the continuous
upward growth of the plant.
The cambium allows further
growth of stems and roots
by increasing their
thickness.
57
Plant Development
The shoot apical meristem
allows the continuous
upward growth of the plant.
The cambium allows further
growth of stems and roots
by increasing their
thickness.
The root apical meristem
allows the continuous
downward growth of roots.
58
Plant Development: Embryogenesis
The fate of different floral structure upon the maturity into a fruit
59
Plant Development: Embryogenesis
The differentiation of the ovary wall into exocarp, mesocarp,
and endocarp in different types of fruits 60
Plant Development: Organogenesis
During germination, water is imbibed,
which ruptures the seed coat.
The radicle emerges from the seed,
which becomes the root of the plant.
The hypocotyl emerges from the
seed, which become the stem.
The cotyledons serve as the primary
embryonic leaves in the seedlings.
Eventually, the epicotyl from plumule
The fate of plumule, hypocotyl, cotyledons,
gives rise to mature leaves.
radicle, and epicotyl in the developing seedlings 61
How do you think plant cells
develop highly organized
structures like leaves, stems, and
roots?
62
Determine the accuracy of each of the following
statements. Write true if the statement is correct and
false if otherwise.
1. During pollination, the seed imbibes water for activation
and develops and forms a seedling.
2. The embryo in a seed is the first sporophyte stage of a
plant.
3. Flowers are vegetative organs that contain the pollen from
the anther and ovule in the pistil, which are needed for
fertilization.
63
Complete the Venn diagram by comparing and contrasting
the given terms below.
Reproducti Developme
on nt
64
● The life cycle of plants, such as bryophytes,
pteridophytes, and spermatophytes, is characterized
by the alternation of generations. In this
mechanism, a plant alternates between the diploid
sporophyte and haploid gametophyte stages.
65
● In a generalized angiosperm life cycle, a plant starts
as a seed.
○ The seed imbibes water for activation, and it
develops and forms a seedling.
○ The seedling will reach an adult tree that will
bloom and produce flowers.
○ The flowers contain the pollen from the anther
and ovule in the pistil that is needed for
fertilization. 66
● Fertilization happens one the pollen penetrates the
ovary of the flower.
● A fertilized ovule then develops to form a fruit
containing the seeds that must be dispersed to
produce new individuals, which will sexually mature.
67
● Both embryogenesis and organogenesis are
important processes that take place after the
formation of seeds in a plant. They ultimately lead to
the formation of functional organs in a plant body.
68
The general pattern of reproductive and developmental phases of the
plant life cycle 69
