Flowers are the reproductive organs of plants that consist of four main parts - calyx, corolla, stamen, and pistil. The calyx is the collective term for sepals, the corolla for petals, and the pistil is composed of the ovary, style, and stigma. Flowers can be classified based on whether they have complete or incomplete floral parts and if they are perfect or imperfect. There are different types of inflorescences that describe how flowers cluster, such as umbels where flowers spread out from a common point, heads where florets crowd together, and catkins which are pendulous spikes bearing unisexual flowers.

1. FLOWERS
Professor Joan S. Awingan

2. A flower is
 the plant’s reproductive organ specializing
in sexual reproduction
 not a single organ, but is a branch bearing
leaflike and stemlike parts on an axis
 arises from the axil of the leaf
 a typical flower consists of four whorls:
calyx, corolla, stamen & pistil

4. Floral Parts
1. Pedicel – the stalk that holds
the flower
2. Receptacle – somewhat
enlarged tip of the pedicel
from which the floral arise
3. Sepal – leaf-like structures
that make up the outermost
circle of the floral parts;
usually green in color;
protects the flower while
it is still a bud

5. 4. Calyx – collective term
for all the sepals
5. Petal – one of the
colored leaf-like
structures that occurs in
one or more circles
within the sepals for
attracting pollinators
6. Corolla – collective term
for all the petals
7. Perianth - collective
term for the sepals &
petals

6. 8. Pistil (carpel) – seed-
bearing organ of the flower;
usually pear-shaped and
found at the center of the
flower.
It is composed of the ovary,
style, and stigma.
Collectively called
GYNOECIUM
9. Ovary – enlarged basal part
of the pistil with one more
locules (cavities containing
ovules that develop into
seeds after fertilization)

7. 10. Style – long and slender neck-
like part extending from the
ovary and serves as
passageway for the
pollen from stigma to the ovary
11. Stigma – sticky part found at
the tip of the style to which
pollen adheres after pollination
12. Stamen – the essential male
part of the flower consisting
of an
anther – where pollen
grains are produced
filament – slender stalk
that supports the anther

8. CLASSIFICATION OF FLOWERS
PRESENCE or ABSENCE OF FLORAL PARTS:
1.COMPLETE - sepal, petal, stamen, pistil
Ex: rose
2. INCOMPLETE
3. PERFECT – stamen & pistil (also called bisexual) but
may lack sepals or petals
4. IMPERFECT – staminate or pistillate (unisexual)

9. KINDS OF INFLORESCENCE
(clustering / grouping of flowers)
1. Spadix – a spike with a fleshy axis, enclosed by a large,
often brightly-colored bract
Ex: Anthurium, calla lily

10. 2. Catkin – a spike with a long and pendulous axis; bears
unisexual flowers only
Ex: Buntot ng pusa (Acalypha hispida)

11. 3. Umbel – the primary axis is shortened and bears at
its tip a group of flowers which have pedicels of more
or less equal lengths, that they appear to spread out
from a common point

13. 4. Capitulum or Head - main axis is suppressed, becoming almost
flat. The flowers (florets) are without stalk that they become crowded
together on the flat surface of the receptacle. The capitulum is
composed of ray flowers along the margin and disk flowers
crowded at the center of the flower

14. 5. Cyathium – consists of a cup-shaped involucre formed by
fused heads
ex: Euphorbia