MONTESSORI INTEGRATED SCHOOL
SECOND QUARTER
NAME: ______________________
SCIENCE 5&6
SUPPLEMENT 4
SECTION: _________ DATE: ___________
NEEDS OF THE PLANTS
We know that plants have certain needs. Plants need sunlight, carbon dioxide,
and water. They also need iron, calcium, nitrate, phosphate, potassium, sulfate,
chloride, magnesium. These minerals are found in the
soil.
Parts of the plants
Leaves
Green leaves are called food factories because
the food-making process takes place mostly in the
leaves. Leaves may differ in size and shape but their
structure is the same. The main parts of a leaf that can
be easily seen are the blade and the leaf stalk, or
petiole is the stem-like part that attaches the leaf to the
stem. The blade is the broad flat part which contains
the green coloring matter called chlorophyll.
Like the
stem and root, the leaf also contains
vascular bundles that appear as veins.
The leaf contains tiny openings called
stomata (singular, stoma). Carbon dioxide
enters the leaves through the stomata.
Water evaporates from the leaves also through the stomata.
KINDS OF RETICULATE VEINS
1. Palmately Reticulate leaf looks like a palm of your hand.
2. Pinnately Reticulate leaf looks like a feather.
Kinds of Leaf
Leaves may be simple or compound.
A simple leaf is a single leaf. It is undivided and
has one blade or lamina attached to a petiole. Some
examples of this kind of leaf are jackfruit, guava and oregano.
A compound leaf consists of many leaf blades attached to a petiole that do the
work of making food. Examples are malunggay, tamarind, fern and acacia.
TYPES OF COMPOUND LEAF
Palmate Reticulate leaf looks like a palm of your
hand. The leaflets of a palmate reticulate are attached
at the same point at the end of the picture.
Pinnate Reticulate leaf looks like a feather. As
you can see the leaflets are opposite to each other.
The main function of plants is to make food. In
some plants, leaves are modified to perform other
functions. The tendrils of the pea plant are modified leaves for support. The Venus
flytrap has very interesting modified leaves. The leaf has sensory hairs at the edges.
When something (such as an insect or even a small frog) touches the hairs, the hairs
trigger the closing of the trap. The spines of the cactus are modified leaves. Their
structure greatly reduces the amount of water evaporating from the plant. They also
protect the animals that might try to eat it.
Roots
Do you wonder how plants get water? Plants eat with their
heads and drink with their feet. It is the roots that suck up the
water from the ground. Water that comes up from the ground
through the roots is slowly taken up to the leaves.
Because roots have a task of finding water in the ground,
the roots have a special sensitivity for water. Wherever there is water, the roots are
going to find it.
In this way, roots help drain water from the ground. In areas without trees and
plants and lots of rain, the land becomes swampy because there are no roots that can
drain the ground.
The part of the root that searches for water is the
root tip. Wherever there is water, the root tip will
grow toward it. If there is an obstacle, the root tip
will go around it. If the obstacle is too big, the roots
will secrete a little acid to break down the
obstacle to make room for them to grow around it.
If we cut the root tip, it can no longer find water. So we can say that the root tip is
like the brain of the root.
To protect this very sensitive root, there is a cap called root cap. The part of the
root that absorbs water is called root hair.
TWO
MAIN
TYPES OF
ROOTS
Roots that grow in bundles are called
fasciculated roots from the Latin word “Facis' '
meaning bundle. An example would be the bean.
On the other hand, roots that grow straight down
are called tap roots. An example would be the
corn.
VARIETIES OF THE ROOTS
In some parts of the earth where there are tropical forests, some roots have
given up living underground. Since on the ground there is a great competition for water.
Some decided to get water from the air. Because of this, they can leave the ground and
take all the water they need. These are called aerial roots.
Some roots, aside from the job of gathering water they also need to get light they need.
They are called root climbers.
In order to climb they need suckers. Some plants where branches are heavy and cannot
grow as pillar roots.
We have another kind which is developed just below the stem; they are called prop
roots.
There are varieties of prop roots called swollen roots that store food for the plant. A
carrot has a conical root, a turnip has a napiform root and a white radish has a fusiform
(shaped like a fish). Another swollen root is a sweet potato. It is a tuberous root.
THE STEM
MAIN FUNCTION OF THE STEM
Since the leaves need sun to make their food and there is great competition for
the plants on the ground, the stem has the job of taking the plants to find light that
enables them to make food. The stem takes the plant up and the roots have the
tendency to grow downward. The stem has the tendency to grow upward. In this way,
the stem may carry the leaves towards the light it needs.
The stem has another job. It carries water and nutrients from the roots up to the
leaves so the leaves can make their own food. It also brings dissolved food from the
leaves to the other parts of the plant. The stem also holds the leaves and the flowers.
TWO KINDS OF STEM
1. Herbaceous stem comes from the Latin word “herba” meaning grass. The stem is
soft and succulent. Examples would be the stems of vegetables.
2. Woody stems grow very tall and live for a very long period of time. Examples
would be the stems of trees.
Parts of Woody Stem
Since the leaves need water in order to make
food, water is carried up to the stem with tubes in
them that have to be protected, so the plants develop
a layer called bark. As these tubes grow, the stem
thickens and this develops rings. Every year the plant
adds a new set of rings and this is how we can tell
the age of the tree.
As the tree grows old, the tube at the center
hardens and the living part or the new tubes move to
the outer part of the stem. This means that the living part of the stem is just inside the
bark.
The innermost part of the stem is hardened tubes. This is where we get our food.
They are very strong and provide support for the tree. The wood is also elastic. When
the wind blows the tree will start to sway and bend.
KINDS OF TUBES
We know that the tube brings water up to the leaves and brings food to the
leaves. These are found inside the bark.
1. Phloem comes from the Greek word “Ploos” meaning
bark. They carry food
and they bring food to the tree.
2. Xylem comes from the Greek word “Xulom” meaning
wood. This is found
inside the part of the stem closer to the wood part. They
carry water from the
roots up to the leaves.
3. Cambium comes from the Latin word “Cambiarre” meaning exchange. This is found
at the center of the tube between the phloem and xylem.
VARIETIES OF STEM
When animals get hungry they go through the bark of trees. They eat the soft
and juicy part of the plants. Sometimes when the weather is too bad, some plants
decide to grow underground for protection, we call these underground stems. But not
all underground stems are alike, an onion is an underground stem we call a bulb.
Another is a tulip. It has succulent and soft leaves. Corm has short-flaky
bulb-like stems. Rhizome is just like ginger. It has root-like stem
that sense out leafy shoots from outer surface and
produces roots from the lower side. Next are tubers, they are short-flaky underground
stems which bear very small scale-like leaves at the axle. Examples: white potato, and
anemones.
Some stems grow erect and tall; they are called erect stems. Stems that grow on
the ground seem lazy; they are called procumbent stems. Stem that is
lying flat with the tip growing upwards is called decumbent stem.
Do you know that stolons, sometimes also called runners. They are
slender, elongated horizontal stems that grow above ground. Next we have the
climbing stem but not all are alike. We have stems that twine around the
branch. We call them a twining stem so they can bring leaves towards the sun.
Example of this is honeysuckle. Another, just hook on towards other branches
and they are called hook climbers.
How does the twining stem climb up to another stem? It makes use of their
tendrils. Tendrils help the plant reach out in order to climb towards the sun. Examples of
this are grapes, ampalaya, patola.
PARTS OF THE FLOWER
1. Corolla is the part of the flower that calls to the insects. It comes from the
Latin word which means “crown”.
2. The flower bud is protected by the calyx which is the Latin word meaning
“bulb”. The calyx is made up of the sepals.
3. Stamen is the part of the flower that make the pollen this is the male part of the
flower. It comes from a Latin word meaning “thread.
PARTS OF THE PARTS
The stamen has anther. The anther makes
the pollen. The filament holds up the anther. The
part of the flower that catches the pollen is the
stigma. Stigma is the sticky and topmost part of the
pistil. The part that holds the stigma is called style.
The pistil houses the ovary. The ovary contains
ovules. Ovules become the seed.
FLOWER TYPES
a. Incomplete /Imperfect Flower
A flower that has either all male parts or all female parts, but not both in the same
flower. Examples: cucumbers, pumpkin, and melons.
b. Complete/Perfect Flower
A flower that has both the male parts and female parts in the same flower. Examples:
roses, lilies, and dandelions.