This instructive YouTube movie examines the enthralling biology of flowers. It begins by describing the fundamental components of a flower, including pistils, stamens, and petals, as well as the meaning behind their various hues and shapes. The process of flower pollination, the involvement of insects in assisting this process, and the components of the flower that are in charge of luring the appropriate insects are next covered in further detail. The film concludes by examining the flower's life cycle and the role that seed dissemination plays in the development of new blossoms. Anyone interested in learning more about the science underlying the beauty of flowers should watch this video.

1. FLOWERS

2. Ancient relics to mordern art,
human history is filled with the
references about flowers

3. what is a flower?
Flower is the main
reproductive part of the
plant.

4. what is a flower?
Angiosperms are plants that
produce flowers.

5. what about those who
don’t produce flower?
They produces cones, sori all short
of things.

6. When did it first floower
bloom?
The fossil record suggest
something, the gentics suggest
something else.
The ‘angiosperm’ gap.

7. “The rapid development as far as we can judge
of all the higher plants within recent
geological times is an abominable mystery”
- Charles Darwin, 1879

8. The oldest flower
in the fossil record
130- million-year-old aquatic
plant Montsechia vidalii
though it may be
Archaefructus liaoningensis
shows dependecy of flowers
on animals

9. Different Parts of
the flower
• Peduncle: This is the stalk of the flower.
• Receptacle: It is that part of the flower to
which the stalk is attached to.
• Sepals: They form the outermost whorl of the
flower. Collectively, sepals are known as the
calyx.
• Petals: They are often bright in colour as
their main function is to attract pollinators
such as insects, butterflies etc to the
flower. The petals are collectively known as
the corolla.
• Stamens: These are the male parts of a flower.
Many stamens are collectively known as the
androecium.
They are structurally divided into two parts:
• Filament: the part that is long and slender
and attached the anther to the flower.
• Anthers: It is the head of the stamen and is
responsible for producing the pollen which is
transferred to the pistil or female parts of
the same or another flower to bring about
fertilization.

10. Different Parts of
the flower
• Pistil: This forms the female parts of a
flower. A collection of pistils is called
the gynoecium.
Pistil consists of four parts
• Style -is a long slender stalk that holds
the stigma.
• Stigma– This is found at the tip of the
style. It forms the head of the pistil.
• Ovary – They form the base of the pistil.
The ovary holds the ovules.
• Ovules– These are the egg cells of a
flower. They are contained in the ovary.

11. Different Parts of the
flower

12. Different types of flowers
• Complete flower - all the 4 whorls are present
• Incomplete flower - any or more than 1 whorls are
absent
• Bisexual / Monoclinous flower - Both abdroecium
ang gynoecium presnt
• Unisexual / Diclinous flower - either the male or
the female whorl present
• Neutrer / Sterile flower - none of the male or
female whorl present
• Nude / achlamydeous flower - calyx and crorolla
absent
• Actinomorphic flower - radial symmetry present
• Zygomorphic flower - bilateral symmetry present
• Cyclic and Acyclic flower - whorls arranged
separately or spirally
• Isomerous flower - whorls are of same numbers or
multiples
• Anisomerous flower - numbers are differnt in

13. Flower is a modified shoot

14. Hypogynous, Perigynous and Epigynous
flowers
• ovary occupies the highest point
• thalamus becomes flat , ovary at the center
• thalamus encloses ovary completely

15. Calyx types
1. Polysepalous
2. Gamosepalous
3. Caducous
4. Decidous
5. Pesistant
Modifications
1. Pappus
2. Leafy
3. Spinous
4. Spurred
5. Hooded

16. Corolla types
1. Polypetalous
2. Gamopetalous
Appendages
1. Saccate
2. Corona
3. Spurred
Forms
1. Cruciform
2. Caryophyllacous
3. Rosaceous
4. Papilionaceous
5. Tublar
6. Campanulate
7. Rotate
8. Hypocrateriform
9. Infundibuliform
10. Urceolate
11. Ligulate
12. Bilabiate

17. Androecium types
1. Monandrous
2. Diandrous
3. Triandrous
4. Polyandous
Number of Stamen whorls
1. Haplostamenous
2. Diplostamenous
3. Obdiplostamenous
4. Polystamenous
Depending on length
1. Isostamenous
2. Didynamous (2 long + 2 short)
3. Tetrastamenous (2 short + 4 long)
4. Heterodynamous
Connective types
1. Discrete
2. Divaricate
3. Distractile
4. Appendiculate
Attachment
1. Adnate, 2. Basifixed, 3. Dorsifixed,
4. Versetile

18. I can
do this
all day

19. Genetics behind flowering
APETALA1 [AP1] are
necessary for the
formation of the sepals
APETALA3 [AP3] and
PISTILLATA [PI] are
necessary for the
identity of the petals
AGAMOUS [AG] are
necessary for the
establishment of the
stamens
SEEDSTICK (STK) as well
as SHATTERPROOF1 and
SHATTERPROOF2 (SHP1 and
SHP2) SEPALLATA (SEP1,
SEP2, SEP3 and SEP4)
genes
(adapted from Theissen 2001;
Zahn et al. 2005; Dornelas and

20. I didn’t find these genes in
gymnosperms
BLAST yeilded no
similarities when sequence
of SEPALLATA was serched
in Pinus sylvestris
Not enough evidance
found about clonning
these genes in non-
flowering plants.

21. Photoperiodism

22. Perception of day length
Phytochrome initiates huge casecading of protein
expression and gene regulation, including
expression of CONSTANS, downstream someway or
another transcription regulation of flowering gene
takes place. Later studies suggested other factors
like vernalisation, proteins like VIN, FLC, LFY are
also involved in the process. In that process PGR

23. Aestivation

24. Placentation

25. Floral formula and floral diagram

26. Floral formula and floral diagram

27. Floral formula and floral diagram

28. Floral formula and floral diagram
We will do that during the pr
classes

29. Floral formula and floral diagram

30. Double fertilization &
Pollen stigma interaction

31. Pollination
Pollinating Agents
Plants utilise both biotic and
abiotic agents for pollination.
Biotic agents – Animals,
insects, butterflies, etc.
Pollination by insects is called
entomophily and pollination by
birds is called ornithophily.
Pollination by vertebrates is
known as zoophily.
Abiotic agents – Wind and water.
Wind pollination is known as
anemophily and pollination by
water is called hydrophily.

32. Pollination
Means of cross pollination
herkogamy - spatial separation
of sexual organs, including
various types of stylar
polymorphisms
dichogamy - temporal separation
of male and female maturity,
i.e. protandry or protogyny
self-incompatibility systems
heterostyly - having styles of
two or more distinct forms or of
different lengths.

33. Infloresnce
Racemose: In racemose
types of inflorescence,
the main axis grows
continuously and
flowers are present
laterally on the floral
axis. Flowers are
present in an acropetal
manner
Cymose: In the cymose
type of inflorescence,
the main axis does not
grow continuously. A
flower is present
terminally on the main
axis. The flowers are
borne in a basipetal
order. The main axis

34. Taxonomic implication of
flowers • Solanaceae - obliquely placed ovary
• Poaceae - spike and spikelet
• Fabaceae - Papilionaceous aestivation
• Cucurbitaceae- Ovary inferior,
Corolla gamopetalous, valvate,
campanulate, Stamens Synandrous or
syngenesious
• Asteraceae - inflorescence head or
papitulum
• Apiaceae - Inflorescence umbel
• Palme - Inflorescence Spadix
etc.

35. Taxonomic implication of
flowers
back in 2018,
Dr. Debabrata
Maity teaching
me about the
180 degree
twisted
labellum of the
orchid
Dendrobium, in
Lataguri

36. Taxonomic implication of
flowers
before that, in
2015, Dr.
Dibyendu
Talukdar
teaching me how
to identify
plants
depending on
their flowers.

38. Palynology
Pollen can suggest a
lot of things, even
help in solving
criminal cases and
historical mystries.
e.g. Max Frei’s
palynological
studies of shroud of
turin.
pollen isolated by my
student Sarada

39. Palynology

40. Palynology and paleobotany

41. Who came first?
The Flowers or the Bees?
The
beautiful
story of
Mutulism
and
coevolution

42. Use of flowers and what flowers
teaches us about the evolution?
The ranges between size of Rafflesia arnoldii or
Amorphophallus titanum to Wolffia australiana or Scopolamine
produced by Brugmansia to citronellol produced by Cymbopogon
nardus; the flowers and flowering plants shows a huge range in
variety.
And dominance of Angiosperms can be attributed to flower
production. Maybe it is like the thumb to the human in the
evolutionary scale.

43. Use of flowers and what flowers
teaches us about the evolution?
Though we don’t know a lot about what is their fate and
evolutionary future.
Say for example how they will evolve in antropozoic meta-
influences.
Obviously
more
studies
are
needed.

44. Still there is a lot
that we don’t know
and understand
about the flowers
or flowering
plants.

45. "Flowers are the music of the ground...
From earth's lips spoken without sound."
-Edwin Curran

46. Thanks for
watching

47. Thank You
Reference
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