Transcript Plant Structure and Function

Plant Structure and Function
What’s the Difference?
What In This Unit
 What makes plant cells work?
 What’s the difference between plant and
animal cells
 What’s inside of plants cells
 The breakdown of Stems, Roots, Leaves
and Flowers
For cells in a plant to multiply
or enlarge a plant must have the
following:
Carbon dioxide, water, oxygen,
nitrogen, phosphorus,
potassium and trace elements.
Plants & Animals
There are basically two
differences between plants and
animals.
Plant have the ability to make
their own food.
The second difference is in
their respiration.
Plants take in carbon dioxide
and give off oxygen.
 Plant
Cells
Plant cells consist of the
following:
Cell Wall: non-continuous
structure surrounding the
plasma membrane
Vacuole: cavity in the
cytoplasm filled with cell water
Cytoplasm: total protoplasm in
the cell except the cell nucleus
Mitochondrion: breaks down
compounds for the cell
Nucleus: a small round body
that contains the nucleolus and
chromosomes.
Plant Tissue Systems
Meristematic Tissue: This is
growth tissue where cell
division and enlargement occur
and is found near the tips of
roots and stem buds.
Simple Tissues
Epidermal tissue: This tissue is
one-cell thick and forms the
outer layer of flowers, leaves,
and many types of fruits.
Parenchyma tissue: This tissue
comprises the fleshy part of
fruits, roots, and tubers.
Its ,main function is to store
food and water.
Complex Tissue
Xylem tissue: This tissue is
called “wood” in vascular
plants.
Its principal functions are to
conduct water and support the
plant
Phloem tissue: This tissue also
conducts material in the plant
and gives the plant support.
Its main function is to transfer
food from the leaves to other
parts of the plant
Parts
of
The
Plant
The Plant Roots
The function of the plant’s
roots are to absorb nutrients and
water from the soil and to
anchor the plant.
The root system can makeup
50% of a plants weight.
There are two types of root
systems soilless roots which
include aerial (ivy), and
aquatic(water lily).
Soilborne roots are classified
into tap and fibrous roots.
Tap roots are those roots which
have a long main root such as a
carrot or pine tree.
Fibrous roots spread out such
as grass
Parts of the Root
At the tip is the roots cap,
where cell division occurs and it
pushes down into the soil.
Root hairs are used to help take
in nutrients
The Plant Stem
The major function of the stem
is to join the root and leaf
systems.
Some photosynthesis also takes
place in the stem.
Parts of the Stem
Node- jointed part of the stem
on which leaf or flower buds
develop
Internode- major part of the
stem between the nodes.
Axillary Bud- bud found at the
leaf axil from which flowers
and branches arise.
Terminal Bud- tip or end of the
shoot were growth takes place.
Petiole- is a stem-like leaf
structure that attaches the leaf to
the stem
Woody Stems
Outerbark- protects the interior
of the plant from insects and
diseases and excessive heat and
cold.
Innerbark- carries food
manufactured in leaves to the
branches, trunk, and roots
Cambium- layer of cells
between the bark and wood
where growth is diameter occur
and the formation of annual
rings.
Sapwood(xylem)- carries sap
from the roots to the leaves
Heartwood- is inactive
sapwood which is darker in
color and gives strength to the
plant
Pith- is the dark center in the
heartwood core.
Leaves
 Leaves are the food factory of the plant
producing all food that is used by the plant
and stored for later use by the plant or by an
animal.
 Leaves vary in shape and size; with most of
them being flat
 The arrangement of the leaves differ
alternate, opposite, whorled,
External Leaf Structures
 The petiole is the stalk that attaches the leaf
to the stem
 The blade which is the flat part of the leaf
 The midrib which is the large center vein
from which all veins extend
 The margins which are the edges of the leaf
Internal Leaf Structures
 The skin of the leaf is called the epidermis
which is a single layer of cells. The
epidermis provides protection from water
loss.
 The guard cells open and close a small
space or pore on the underside of the leaf
called the stoma
 The stoma allows the plant to transpire.
This gives off moisture and exchange of
gases.
In the inner part of the leaf are the
chloroplast. The chloroplast are filled
with chlorophyll which give the leaf
it’s green color.
With the use of chlorophyll , minerals,
sugars sunlight and carbon dioxide the
plant goes through photosynthesis
The formula for photosynthesis is the
following:
6CO2 + 6 H2O + 672 Kcals (light
energy) = C6H12O6 (Glucose) + O2
Flower
The purpose of the flower is the
reproduction of the plant. This can be
done through fruits and seed.
The reason flowers are colorful is to
attract insects for pollination
Parts of the Flower
 The sepals are the green leaflike part of the
flower located at the base and are used to
protect the flower bud.
 The petals are actually leaves and are the
most striking part of the flower
 The stamen makes up the male reproductive
part of the plant. This includes the anther
which holds the pollen. The filament is the
slender stalk that holds the anther
The pistil is the female reproductive
part of the flower. This includes the
stigma which is sticky and catches the
pollen, the style which is a long tube
that carries to the ovary, the ovary is
where the egg is produced.
A complete flower has both male and
female parts
An incomplete flower contains only
one of the parts