THE REPRODUCTIVE ORGANS
The Flowers
Structure
Reproductive Parts:
●​ Flower, Pollen Grain, Ovule
●​ Part of the chute
●​ Involves exchange of genetic material
(sexual reproduction)
●​ Root, stems, and leaves may also be
involved (asexual; no exchange of
genetic material); vegetative organs
Flowers
“Androecium”
flower
- composed of Filament
which holds the
- Anther (has pollen grains
that have the reproductive
cells; develops sperms)
Pistil
“Gynoecium”
- Stigma: On top of the
pistil
- Style: Tube-like structure
- Ovary: houses ovule
- Ovule: has reproductive
cells (egg cell and
endosperm cell)
Simple Flowers: A flower is alone or just has 1
stalk and a flower on top “Solitary Flower”
Multiple Flowers: Many flower held by a single
stalk “Infloresence” (cluster of flowers)
Part
Function/Description
Pedicel
Stalk
Receptacle
- can be very fleshy
- can outgrow the ovary in
the process of
development
- not all flowers have it
Sepal
- “Calyx” whirl of leaf-like
structures
- usually green in color
- smaller than inner whirls
- can be considered a
modified leaf (due to
venation)
- not directly involved in
reproduction
Petals
- “Corolla” inner whirl
- bigger and more colorful
than sepals (for attraction
of pollinators)
- can be considered a
modified leaf
- not directly involved in
reproduction
Stamen
- Usually numerous in 1
THE REPRODUCTIVE ORGANS
Complete vs Incomplete Flowers
- Presense or absence of the 4 major parts of
the flower (sepals, petals, stamens, and pistil)
- Complete: has all major parts
- Incomplete: has major parts but is also
missing some major parts
Ovary Position
- Essential plant characteristic
- Hypogynous Flower: ovary “superior ovary”
is situated above the insertion of the other parts
of the flower (sepal, petal, pistil).
- Perigynous: ovary “hemi-inferior” is halfway
the other parts of the flower. (within)
- Epigynous: ovary “inferior ovary” is below the
point of insertion of the other parts. of the flower
Type of Symmery
Perfect vs Imperfect Flowers
- Refer to the 2 essential parts of the flower (for
reproduction); stamen and pistil
- Perfect: stamen and pistil
- Imperfect:
Staminate / Male Flower (missing pistil),
Pistillate /Female flower (missing stamen)
Monoecious vs Dioecious plant
- About the plant bearing flowers
- Can only be Incomplete and Imperfect flowers
- Monoecious: has both male and female flower
in 1 plant
- Dioecious: separate male and female flower;
is either
Male Plant: has only staminate flower
Female Plant: has only pistillate flower
Characterizing flowers based on the:
Nature of Corolla
- Gamopetalous: the petals are partly united
with each other
- Polypetalous: the petals are totally free from
each other (from the pit to the base)
- Apetalous: doesn’t have any petals
- Apopetalous: distinc/separate petals (?)
- Radial Symmetry: any part of the flower looks
exactly the same as the other parts (when cut);
Regular/Actinomorphic Flower
- Bilateral Symmetry: Mirror images; only the
left side will look like the right side;
Irregular/Zygomorphic Flower. (petals can be
given specific terminologies depending on their
characteristics ex.: upper lip and lower lip)
Inflorescence:
- Composite Flowers
- Spadix; Anthurium sp.
- Phallic (monoecious); Amorphophallus sp.
- Amorphophallus titanium (biggest in the world)
Single Flower:
- Rafflesia (biggest); can be male or female
- fragile; woody vines do photosynthesis;
parasitic flower
THE REPRODUCTIVE ORGANS
Stamen and Pistil
- more essential parts of the flower
- Stamen: usually are numerous in 1 flower
- Pistil: solitary; occurring in the middle
Stamen, Anther, Pollen
Structure of Stamen