Plant reproduction can occur through sexual or asexual means. Sexual reproduction involves flowers and production of seeds, while asexual reproduction is vegetative and involves propagation through stems, leaves, or underground structures. The life cycle of flowering plants includes germination of seeds into seedlings, growth and maturation of plants, flowering, pollination and fertilization to produce seeds which then disperse and the cycle continues. Fruits aid in seed dispersal through various adaptations for wind, animal, or explosive dispersal. Genetically modified crops aim to introduce traits like pest resistance, disease resistance, drought tolerance, and increased nutrients, in order to address issues around food security. However, GM crops also face opposition around safety and environmental concerns.

1. Plant Reproduction

2. Reproduction of plants
Plants
Non-
Flowering
flowering
By Flowers & Vegetative Spores
Cones
Seeds reproduction formation

3. Plant Asexual Reproduction
Above ground Stems arch over and
take root at the tips, forming new
plants (Forsythia, Raspberry and
Strawberry)
Horizontal above ground stems are
called stolons

4. Plant Asexual Reproduction
 Underground stems that serve for food storage
and reproduction. Rhizomes, bulbs, corms and
tubers

5. Plant Asexual Reproduction
 Leaves—Mitosis along the meristems at the leaf
margins produce tiny plantlets that fall off and
can take up an independent existence.

6. Advantages Of
Vegetative Propagation
 The young plant uses the food resources
of the parent plant, while it is developing.
 Only one parent plant is involved.
 Good and desirable parental characters
are retained in the offspring.
 The new plant formed matures more
rapidly than the plant which grows from
seeds.
 A large number of desired varieties of
plant are produced in a very short time.

7. Disadvantages Of
Vegetative Propagation
 No new varieties are produced.
 Over crowding of the vegetative produced
plants leads to severe competition for
survival among them.
 Lack of variety leads to reduce resistance
to disease and changes in the
environment.
 Colonization of the new localities is
unlikely. Thus the plants are not widely
distributed.

9. The life cycle of a
flowering plant
4. Pollination
3. Flower
blossom 5. Fertilization
2. Plant
development &
maturation
6. Seed/Fruit
formation
1. Germination
7. Seed
dispersal

10. Seed Structure
Seed coat / Testa
Forms a tough Plumule
protective layer Embryo
shoot
Embryo –
grows into
seedlings
Cotyledon / Food store
Provides the embryo Radicle
plant with food. Embryo
root

11. Seed Germination

12. Plant grow & mature

13. The Parts of a Flower
Most flowers have
four parts:
This is a bisexual plant!!
sepals,
petals,
stamen,
carpels / pistil

14. Carpel
Stamen

15. Petals
Colourful to attract the insects pollinators

16. Sepals
Protect the flower bud
Carry out photosynthesis

17. Nectaries
give out sugary liquid to attract insects

18. Stamen
- Pollen grains
-Anther
- Filament

19. Pistils
- Stigma
- Style
- Ovary
- Ovule
• Receive
Style
• Protect ovule
pollen • Supports • Ovule becomes seed
grains stigma after fertilization
Stigma Ovary

21. Pollen
Pollen grains
Male gametes
Stigma
Pollen tube
Ovary
Ovule
Female gametes

22. Pollination
Pollination involves the transfer of pollen
(male gamete) from the anther to the
stigma (outermost female part)

23. Types of pollination

24. Self pollination
No variation

25. Types of pollination
Cross – Pollination
 Pollen of a plant
pollinates another plant.
 Still genetically the
same, with variations

26. Advantages of Cross Pollination
Better Quality Fruits
Healthier Plants
Resistant to disease

27. Increase the chance of Cross-pollination

28. Plant pollinators - Animals

29. Plant pollinators - Wind

30. Unpollinated Pollinated
Flowers flowers

31. Insect Pollinated Plants

32. Some flowers provide food (e.g., nectar or
pollen) to their pollinators
Honey bee collecting
pollen and nectar

33. Wind Pollinated Plants

34. Pollination Comparison
Structure Wind Insect
Pollinated Pollinated
Size Small Large
Petals dull bright colour
Scent none scented
Pollen light sticky
Stamen dangling outside inside flower
Stigma feathery sticky
Nectar none makes sugar

35. Pollen grain and Fertilisation

36. Formation of Pollen Tube

37. Pollination >>> Fertilization

38. After Fertilisation
Once fertilization has taken place the
zygote (fertilized ovule)becomes a seed,
and the ovary becomes a fruit.
The petals die and fall off.
The plant seeds are in the fruit.

39. Development of the seed and fruit
Ovule >>>> seed
Tissues of the ovary >>>> fruit

40. Development of the seed and fruit

41. Development of the seed and fruit
There are many kinds of fruits
Carpels
Flower
Stigma
Stamen
Ovule
Carpel
Each
(fruitlet) Stigma segment
develops
Seed
from the
carpel of
Stamen
one flower
Pea
Raspberry Pineapple
Simple fruit - single carpel of Aggregate fruit - many separate Multiple fruit - many carpels
one flower carpels of one flower of many flowers

42. What are fruits like?
The fruits can be:
- soft & fleshy
- hard & dry
• What fruits can you think of?
• What are their seeds like?

43. Soft & Fleshy Fruits

44. Hard & Dry Fruit

45. Seed Dispersal- why?
Seeds must be carried away (dispersed /
scattered) from the parent plant to:
• Reduce overcrowding
• Reduce competition for:
- Water
- Light
- Nutrients

47. How birds and animals help seed
dispersal
Birds and animals
eat the fruits and
excrete the seeds
away from the
parent plant.

48. Development of the seed and fruit
Fruits aid seed dispersal
Many dry fruits are wind dispersed

49. Development of the seed and fruit
Fruits aid seed dispersal
Some dry fruits are animal dispersed

50. Development of the seed and fruit
Fruits aid seed dispersal
Many fleshy fruits are animal dispersed

51. Development of the seed and fruit
Fruits aid seed dispersal
Some fruits disperse seeds explosively
(e.g., some mistletoes)

52. Development of the seed and fruit
Fruits aid seed dispersal
Some fruits make seeds buoyant,
to aid dispersal by water

53. Seed Dispersal
Dispersal Description Seeds/
method Fruits
Wind Seeds are designed to
travel as far as
possible.
May have extensions
which act as
parachutes or wings.
Fruits may be shaken
like a pepper pot.

54. Seed Dispersal
Dispersal Description Seeds/
method Fruits
Animal Some have little hooks
(external) or sticky substances so
they stick onto the
animal’s fur, are
carried away and
rubbed off later.
Some carried away by
animals and dropped.

55. Types of Seeds

56. Dicotyledonous Seed

58. Stages of Seed Germination
Absorption of
Testa Radicle Grows Lateral roots
water through
Ruptures downwards formed
micropyle
Plumule Cotyledons is
Hypocotyl Hypocotyl
exposed to pulled above
straighten lengthens
sunlight ground
1st foliage
Second
leaves Photosynthesis
leaves
exposed

59. Seed Germination Process

61. Cotyledon
Hypogeal remains
underground
Types of
seed
germination
Cotyledon
Epigeal above the
ground

62. Conditions for Seed Germination

66. GM Crops & Foods

67. Food
Crisis

68. Advantages of GM foods
(1) Pesticide alternative Crop loss due to pests can be financially
crippling for farmers which is the reason most farmers use
pesticides. As an alternative to pesticides, crops such as corn and
soybeans can be genetically altered to resist pests - making the
farmer, the consumer and the environmentalist happy.
(2) Disease resistance There are many diseases - including
fungi, viruses and bacteria - that can attack crops. With new GM
technology, scientists can create crops that are genetically resistant to
these attackers.
(3) Cold tolerance In order to prevent cold temperatures from killing
crops, scientists can take a gene that causes cold water fish to produce
"antifreeze", and place it into certain plants that are susceptible to
frost.
(4) Drought resistance Genetically altering crops to resist drought
and grow in otherwise non-ideal conditions (like poor soil
quality), farmers are able to grow crops in areas that were previously
unsuitable for agriculture.
(5) Adding nutritional value Scientists are able to identify
nutritional deficiencies in specific parts of the world, and genetically
enhance the corn in order to satisfy the nutritional need.