Introduction to the Kingdom Plantae and plant morphology with examples, images and explanatory diagrams.

1. Pablo León Cruz www.biogeosfera.es
KINGDOM PLANTAE : INTRODUCTION & PLANT MORPHOLOGY

2. What are plants?
Plants are organisms that are....
 Multicellular: They possess thousands of cells.
 Eukaryotic: All cells possess a nucleus.
 Autotrophic: They transform inorganic matter into organic
matter.
 Able to perform photosynthesis.
 In possession of chlorophyl, a green-hued pygment.
 In possession of cells and specialized tissues.
 Fixed on the ground and unable to move.

3. Why are plants so important?
Plants are important for the biosphere because…
 Through photosynthesis they produce the oxygen all living
organisms breathe.
 They absorb carbon dioxide and air pollutants, lowering
their concentration in the atmosphere.
 They regulate the temperature and cool the environment.
 They are the starting point of our planet’s ecosystem’s
chain foods.

4. Why are plants so important?
Plants are important for the biosphere because…
 They create habitats for many organisms, like insects,
worms, small mammals and birds.
 They prevent soil erosion, surrounding it with their roots,
and enriching it by releasing organic remains.
 They provide many resources: food, medicine, wood, fuel,
building materials...
 They are used as decoration for their beauty in parks,
gardens, courtyards, terraces and indoors.

5. Plant morphology
The root
The root is the organ that usually grows underground, forming a
branched structure capable of absorbing nutrients and fixing
the plant to the ground. Their main functions are:
 Nutrient absorption: water and mineral salts.
 Fixing the plant to the ground to prevent its fall.
 Accumulation of reserve substances, like in carrots.

6. Plant morphology
Parts of the root
The roots of plants have the
following parts:
 Neck: Part located at the level of the
soil surface that separates the stem
from the root.
 Main root: Root that grows vertically
downward to anchor the plant in the
substrate.
 Secondary root: Branches that start
from the primary root. Its function is
water and nutrient absorption.
 Absorbent hairs: Small villi usually
present in secondary roots that absorb
water and mineral salts.
 Root cap or calyptra: Capsule that
protects the end of the roots.
Neck
Root Secondary
roots
Absorbent
hairs
Growing
root
Root cap
Main
root
Absorbent
hairs

7. Plant morphology
Root types
Axonomorph
Branched Fasciculated
Tuberous
Napiform Adventitious

8. Plant morphology
The stem
The stem is the organ that supports the aerial part of the plants,
grows in the opposite direction to the root and on it the leaves,
flowers and fruits develop. Its main functions are:
 Nutrient transport inside the plant.
 Hold the leaves, flowers and fruits.
 Contribution of stability to the plant so that it grows upright.

9. Plant morphology
Parts of the stem
Plant stems have the
following parts:
 Node: Bulky area of the stem in
which the buds are found and
from which new stems are born.
 Internode: Portion of the stem
that separates two nodes.
 Axil: Point where the branch or
leaf meets the stem.
 Bud: Small sprout that can lead
to new stems.
 Neck: Part of the stem that joins
the root. v
Leaf
Internode
Internode
Node
Node
Bud
Petiole

10. Plant morphology
Types of plants according to the stem
Depending on the size and type of stem, plants can be classified
into three large groups:
Herbs: Small, soft stem and green color.
Bushes: Woody stems that grow from the base.
Trees: Trunk with woody stems from a certain height.

11. Plant morphology

12. Plant morphology

13. Plant morphology

14. Plant morphology

15. Plant morphology
The leaf
The leaf is the generally flattened organ of plants responsible for
carrying out photosynthesis. The leaves are varied according to
their size, shape and color. Its main functions are:
 Photosynthesis: they synthesize organic substances from
carbon dioxide and water using sunlight and they expel
oxygen.
 Respiration: they absorb oxygen and expel carbon dioxide.
 Evapotranspiration: they expel excess water through
stomata.

16. Plant morphology
The parts of the leaf
The leaves of the plants have the following parts:
 Blade: Flat, thin and widened part of the leaf.
 Upper side: Upper part of the blade.
 Lower side: Lower part of the blade.
 Margin: Leaf contour.
 Petiole: Structure that connects the blade with the stem.
 Veins: Branches of the petiole inside the leaf.
Petiole
Petiole
Base
Base
Margin
Margin
Veins Veins
Upper side
Upper side
Lower side
Bud
Bud
Stem
Blade
Apex
Apex

17. Plant morphology

18. Plant morphology

19. Classificationof
theleaves

20. Plant morphology
The flower
The flower is the structure that contains the reproductive
organs of the plant. Most of the flowers are hermaphrodites:
they have both male and female reproductive organs. Their
main functions are:
 Reproduction of the plant.
 Attraction of pollinating animals through the color of the
petals, the smell of the flower, the nectar...
 Fruit formation after fertilization.
 Seed production, which are inside the fruit.

21. Plant morphology
Parts of the flower
Pedicel
Calyx
Sepal
Petal
Stigma
Style
Ovary
Ovules
Pistil
Anther
Filament
Stamen

22. Plant morphology
Parts of the flower
Plant flowers have the following parts:
 Pedicel: Elongated structure that joins the flower with the
stem.
 Floral wrap: Structures that protect the reproductive organs.
 Calyx: it is formed by sepals, which are green and are on the outer part
of the flower.
 Corolla: It is formed by petals, which are of different colors and have
the function of attracting pollinators.
 Reproductive organs: They produce gametes.
 Stamens: Elongated structures formed by a filament that supports the
anther, where the pollen grains (♂) are.
 Pistil: Bottle-shaped structure. The upper part is called stigma, the
neck is called style and the lower part contains the ovary, which
produces the ovules (♀).

23. Plant morphology

24. Plant morphology

25. Plant morphology

26. Plant morphology

27. Plant morphology

28. Plant morphology

29. Plant morphology
The fruit
The fruit is the organ formed from the fertilized flower that
contains the seeds until they ripen and then contribute to
disseminate them. It can be fleshy or dry. Its main functions are:
 Seed protection.
 Seed dispersion.
Once the ovum has been fertilized, it becomes a seed and the
ovary begins to grow rapidly to become the fruit.

30. Plant morphology
The fruit
The fruits of the plants have the following parts:
 Exocarp: External layer that surrounds the fruit and that corresponds to
the fruit peel.
 Mesocarp: Intermediate layer that forms the edible part of the fruit.
 Endocarp: Internal layer that surrounds the seed.
 Seed: Structures that are part of the fruit that can originate a new plant.
Exocarp Exocarp
Mesocarp Mesocarp
EndocarpEndocarp
Peach Apple OrangeTomato
Pericarp: Exocarp + Mesocarp + Endocarp

31. Plant morphology

32. Plant morphology