of a plant
We depend on nature for all our basic need. Plants are one of big groups of nature. They
are autotrophic which means they can make their own food. We obtain many things
from plants such as cereals, pulses, vegetables, fruits, wood, fibre, rubber,
gum, tea, coffee etc.
Plants includes trees, herbs, bushes, grasses, vines,
ferns, mosses, and green algae. The scientific study of plants is known as
botany. Fungi and non-green algae are not considered as plants. Basic parts of plants
are roots, stems, leaves, flowers, fruits, and seeds. Each part of a plant has
a very important function.
Root System- Root is the underground part of the
plants body and grows towards the force of gravity. It fixes the plant within
the soil and absorbs water and mineral nutrients from the soil. It stores
Roots- It consists of one main root growing downwards from
which lateral roots develop which may initially grow horizontally then turn
downward. Taproots are also important adaptations for searching for water and
minerals from deep within the soil. Examples:
sugar beet or carrot etc.
Roots- It consists of a dense mass of slender roots that
arise from the stem. The roots grow downward and outward from the stem,
branching repeatedly to form a mass of fine roots. Example: lilies, grasses, palm etc.
In some plants the roots are modified to do special
tasks. They are called Modified
Some of them are:-
These consist of a thickened roots due to the accumulation of high-energy storage
compounds, usually starch. Example: - carrot, sweet potato, cassava, raddish
These fibrous roots remain aerial, i.e. they do not enter the soil. It performs
special functions such as water retention, photosynthesis, and support. For
example- Old banyan trees have aerial roots hanging down. It provides support
to the tree.
Aquatic Roots - These are specialized roots in some
plants that grow in watery places and which function mainly for water and
nutrient absorption. Its root system consists of long fibrous roots. Example:
Shoot System- It is the aerial part of the plant body
and enables a plant to grow taller to gain access to energy-giving light, and
helps plant to prepare food. It is composed of erect stems on which are
attached leaves, flowers, branches and buds. Leaves are attached to the stem at
regions called nodes.
It supports the upper parts of plants. It carries the water and nutrients
needed for plants to grow from roots to leaves and food produced by the leaves
to other part of plants. Stems also store food for the plant.
Typical stems are located above ground, but there are modified stems
that can be found either above or below ground.
various climbing plants, such as the grapes, some parts of stems are modified
into coil like structures called tendrils. They are weak, so they take the
support of other structures to help the plants to climb up and grow.
Runners or stolons - Stems that grow in a creeping fashion
horizontally above the surface of the soil are called runners, or stolons. Nodes
of these stem if touches soil, give rise to new plant. Example –water melon,
Water storing stem-Some
cacti and a few other kinds of plants have stems that look like leaves. They are
green and thus manufacture and store food.
Underground modified stem-
potato, garlic, onion and ginger are example of underground stem.
are the parts of the plant where food is made by the process of photosynthesis.
That’s why leaves are called the food making factories of green plants. Chlorophyll
(green pigment) present in the leaves uses the energy in sunlight to turn water
(H2O) and carbon dioxide gas (CO2) into sugar and oxygen gas (O2). Leaves are
of different shapes and sizes. The outer
surface of the leaf has a waxy coating which protects the leaf. The flat
surface of the leaf is called leaf blade or lamina. It has veins running across
within the leaf. Tiny opening on the surface of the leaves called stomata helps
in the exchange of gases.
Parts of leaf
are modified as spines in cactus for protection. Due to the scarcity of water
in desert, in some plants leaves are modified to form spines.
are spring like structure that is coiled spirally. They are leaves modified for
support and when they come in contact with any structure, they coil around that
In plants like onion, the leaves are modified as storage organs.
These leaves protect stem at the base of the onion.
most modification in leaves is related to the need of water by the plant.
Needle like leaf modification is seen in plants like pines, firs etc.
Venus fly trap plants are designed to capture and digest insects
between the folds of their specialized leaves.
is a plant with flower-like spring leaves near its flowers.
are the most attractive part of a plant. Each flower types have a different
physical structure, color and scent from those of other flower type plants.
Petals and the flowers smell attract insects and bees to pollinate the
flower. After pollination, the petals
fall off and seeds develop in the part of a flower called the ovary. The ovary itself usually becomes the fruit.
is the process by which pollen is transferred from the anther to the stigma of
the plant. Some of the agents of pollination are insects, wind, birds, mammals,
The parts of a flower that are often brightly colored or unusually shaped to
attract pollinators. They are the most attractive part of the plant.
–These are small and green in color composing the outermost part of a flower.
It encloses and protects the bud and may remain after the fruit forms.
The pistil usually is based in the center of the flower and is consist of three
parts: the stigma, style, and ovary.
Stigma - It is the waxy, sticky bulb in the
center of flowers and is the part which receives pollen.
Style - It is a long, slender stalk that
connects the stigma and the ovary.
Ovary- The ovary is located at the bottom
of the style
It is the pollen-producing part of a flower is consist of two parts: Anthers
Anthers – It is pollen producing structure.
These are generally yellow in color.
Filament – It is a thread like structure
which holds anthers.
Fruit and Seed
The fruit is a fleshy or dry ripened (mature) ovary of a plant, enclosing the
seed or seeds. Most plants grow from seeds. A seed (mature ovule) is a miniature
plant with a protective outer covering called the seed coat, usually with some
Seeds are dispersed either by wind, water or animals. On getting
air, water and sunlight, seed grow into baby plant. Most plants grow in the
ground, with stems above, and roots below.
Seeds dispersal means movement of seeds from parent plant to
another place. Dispersal of seeds is stops overcrowding and to create new
Some seeds are scattered by wind
are usually enclosed in wing-like husks or fluffy coverings that help
them to fly away long distance from the parent plant. For example,
Dandelion seeds develop very light and fluffy parachute-like structures. These
help the seeds to float in the wind and delay their fall to the ground.
Aquatic plant and plants that grow beside water have buoyant,
waterproof coverings that allow them to float and disperse their seeds by
Fruits which float such as those of the water lily and the coconut
palm are carried by water and can travel for long distance.
By Animal and Humans
Seeds with sticky hairs, bristles, hook, or barbs are transported
by sticking to the fur of animals or on the clothing of human beings and are
carried long distance. Birds and other animals eat the fleshy fruits and
discard the seeds or they may eat both but the seeds are not digested and are
passed out as waste, and are ready to grow.
By Explosion of fruit
Some plants distribute their seeds by ejecting them with force when
they are dried in the sun so that they fall well away from the parent plant.
This is explosive dispersal. An example of this is plants which belong to the
Pea Family .They produce seed pods which dry in the sun and suddenly split into
two halves and disperse their seed.
Reproduction is the production of new individuals or offspring in
plants. Not all new plant grows from a seed. There are some plants that employ
vegetative propagation and grow new plants. Vegetative propagation is a process by
which new organisms arise without production of seeds or spores. In this
process only one plant is involved and the offspring (new plant) is genetically
identical to the parent.
New plants grow from parts of the parent plant.
Many parts of
plant are used for the asexual reproduction
Stems- Aerial weak stems when touches the ground, give of adventitious
roots and if it detach from the parent plant, newly formed roots develops into
an independent plant ex- strawberry, grass. Other examples of stem propagation
are ginger, banana, turmeric etc.
Leaves-In some plant, buds develops on leaf margins. These buds
remain dormant till leaf remain attached with plant but develop into new plant
when fall off from the plant and come in the contact of soil. Ex -Bryophyllum
The roots of some plants develop adventitious buds on them. Example:
guava, dahlia & sweet potato. These buds sprout under suitable conditions
and when detached from the parent plant turns into new plant.