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Unit
5 Reproduction and
Modification in Plants

Pollination in Plant

Learning Objectives
After studying this lesson, students will be able to:
 understand how a flower becomes a fruit with seed through pollination
and fertilization.
 acquire knowledge about pollination and pollinators.
 differentiate self pollination and cross pollination in plants.
 know about the modification of root, stem and leaves.
 understand how these modifications are useful to animal and human being.

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The process by which plants and animals

Introduction
produce young ones and increase their number
We know already that flowering plants have is known as ‘reproduction’. Drumstick tree can
root, stem and leaves. They are called vegetative be grown from both seeds and stem cuttings.
organs. Flowers, fruits and seeds in a plant are When plants are reproduced from the seeds we
called reproductive organs. In earlier classes we call that process as sexual reproduction. All
have seen that new plants can be grown from other ways of reproduction without seed are
seeds. In this lesson, we are going to know
called as asexual reproduction.
how a flower changes itself into a fruit, and the
modifications of root, stem and leaves of a plant.

5.1 Reproduction

ACTIVITY 1
Aim
To raise a new generation of plant from
watermelon and potato.
Materials required
Two pots with soil, potato, watermelon
seeds and water.
Reproduction in plants
Procedure
Fill both pots with soil mixed with compost ACTIVITY 2
or manure. Take a young potato. Ensure Find out how these plants reproduce.
that it is not dried up and the skin still
Reproductive Part
looks fresh. Bury a potato in one pot. Sow Sl. Name of
No. the plant
watermelon seeds in another pot. Pour Seed Stem Cutting Layering
water regularly and maintain the plant. 1. Mango
Observation 2. Potato
After few days, we can see a single plant
3. Banana
arising from a buried potato. Plants arise
from the pot sowed with watermelon 4. Tamarind
seeds. Each seed produces a plant. 5. Rose
6. Mustard
We can see from this activity that
7. Coriander
watermelon plant is produced from that seeds.
Potato plant is not from seed, but from the stem 8. Moringa
tuber (vegetative part). Seed is not only the 9. Pumpkin
source for new generation, even vegetative part 10. Radish
of a plant can be used to produce a new plant.
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5.2  Sexual reproduction Hibiscus flower

Bud Opened flower
Seed is produced from a flower by the Green colour Bright colour
process of pollination and fertilization. This is Sepals Petals
known as sexual reproduction. To understand Dissected Hibiscus flower
how seeds are formed in a flower, first we need Bud Opened flower
to understand parts of a flower. Curled petals Expanded petals
Small tube with Expanded tube with
ACTIVITY 3 yellow lobes - Anthers yellow lobes -Anthers

Take a flower. Dissect it longitudinally

as shown in the figure and find the parts
inside the flower. Can you identify the male
reproductive part, androecium (stamen,
filament and pollen sac)? Carefully observe
Datura flower
the female reproductive part, gynoecium
(ovary, style and stigma). If they are not Bud Opened flower

seen clearly, gently pluck off the sepals and Green colour White colour
petals. Make a drawing of the parts and Sepals Petals
arrange them in your notebook.
Dissected Datura flower
Bud Opened flower
Curled petals Expanded petals
Small yellow lobes- Expanded yellow
Anthers lobes-Anthers

In a bud, we can see a green colour, leaf like

L.S. of a flower showing its parts
structure which cover the whole bud or flower.
Each of these green leaf like structure present as
5.2.1  Parts of flower an outermost layer is called as sepal. This outer
most ring of sepals is known as calyx.
Let us compare few buds and opened
flowers of Hibiscus and Datura. Observe bud Petals are the largest part of flowers.
and opened flower of Hibiscus and Datura. They are often attractive, brightly coloured,
We can tabulate the characteristics of Hibiscus sometimes sweet scented and attract the insects.
and Datura flowers as below. This ring of petals together is called corolla.

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SEXUAL REPRODUCTION IN PLANTS

Petal Sepal
Attracts insects and birds
for pollination.
Flower Hold and cover the young
developing flower bud.
The Reproductive organ of a plant.

Stamen
Male part of a flower
that produce pollen grains. Pistil
Female part of the
flower contains
ovary,style
and stigma.
Pollination
The pollen grains reaches
the stigma.

New plant
Seed germinates and
gives rise to a new plant.

Fertilization
Fusion of male and
female gametes.

Seed
Fertilized ovule
becomes seed.

Fruit
Fertilized ovary
becomes fruit.

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This is the ovary. Seeds are produced in this part.

On top of the ovary there is a slender tube like
structure called style. The top most sticky tip of
Petal
the style is stigma. Pollen grains are received by
the stigma. This is the fourth whorl of a flower.
Sepal
5.2.2  Types of flowers
Flowers can be divided into two types.
They are explained below.
Complete Flower
Sepal and Petal
If all the four whorls - calyx, corolla, stamens
Inside corolla, in Hibiscus, we can observe
and pistil are present, then it is called as complete
a long tube on which many stamens are
flower. Complete flowers are bisexual flowers.
arranged. But, in Datura we can see only five
Incomplete Flower
stalked structures, stamens. This ring or whorl
of a flower is called androecium. Each stamens If any of these four whorls is missing, then it
consists of two parts – a stalk called filament and is called as incomplete flower. Incomplete flowers
a lobe called anther. If you touch these lobes in a are unisexual flowers. There are two types of
mature flower, we can get a powdery substance unisexual flowers, male flower and female flower.
called pollen grains (male reproductive part). The flower with androecium and without
gynoecium is called as male flower and the one
with gynoecium and without androecium is
known as female flowers.

Sunflower is not a single flower.

It is a group of flowers clustered
together. A group of flowers
Androecium - Male part of the flower arranged together is called inflorescence.
Inside androecium whorl, we can find a female Tridax procumbens, looks like a single
reproductive part of the flower, called gynoecium. flower, but it is an inflorescence. Leaf juice
You will find this part with a swollen bottom part. of this plant is used to cure wounds and cuts.
Stigma
Style ACTIVITY 4
Make a flower album
Ovary Collect some flowers and press them between
pages of newspaper or book. Place two thick
Ovule sheets and keep a heavy object, such as brick, on
the top to apply pressure. Turn the sides every two
to three days. Allow flowers to dry completely.
Collect the dried flowers and paste them in an
album. Now, your flower album is ready.
Gynoecium – Female reproductive part
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ACTIVITY 5
Using the information from the above diagram complete the following table:
Name of the flower Complete / Incomplete Unisexual / Bisexual Male / Female
Hibiscus
Pumpkin
Rose
Coconut
Jasmine

ACTIVITY 6
Stigma Petal
Style Once flower buds appear, immediately
identify ten female flower buds from a
Ovary Anthar pumpkin plant. Tie a plastic bag around
each bud so that no outside material can
enter inside. Ensure to make small holes
with a pin to allow air flow. Wait for two to
Pedicel Sepal three days to bloom.

Bisexual Flower

Stigma
Style Petal
Female Male
Overy Choose three to four male flowers. Pluck
the stamens of these flowers and dust the
pollen grains in a sheet of paper and collect it.
Open five out of ten bags containing female
Sepal
Pedicel flowers. Brush the collected pollen grains on
the stigma with a soft paint brush. Take care
Unisexual Flower
not to damage the stigma. After few days we
can see that flower in all bags that were not
5.2.3 Pollination
opened at all would wilt without forming
We know that flowers of a fruit, while most of the flowers to which
pumpkin are unisexual - that pollens have been applied bear fruits.
is some flowers are male while
many are female flowers. We The process by which pollen grains reach
can easily identify the male and female flower stigma is called as pollination. The flower that
of pumpkin, even before the buds bloom. To receives pollen grains is called pollinated flower
understand how a flower develops into fruit, let while the one that did not receive pollen grains
us perform an experiment on pumpkin plant. is called as unpollinated flower.
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In the above experiment we transferred the are carried by wind to other flower. Insects,
pollen grains from male flower to the female birds are also agents of pollination. Bees,
flower. This is called as an artificial pollination. butterflies and variety of birds hover around
However, in nature there are many ways in flowers. They help to carry pollen from one
which pollen grains reach the stigma of the flower to another. Pollen grains stick to their
flower and it is called as natural pollination. legs, wings or abdomen when they move from
one flower to another. This is called as cross
pollination

When you shake stamens, pollen grains

fall. Thus, when wind shakes the flower or
when a butterfly agitates the flower, pollen
grains could fall onto the stigma of the same
flower. Some plants that have both the male
and female parts within a single flower
In some plants like grasses, pollen grains (bisexual) pollinate by this means. This is
are light. Stamens shed pollen grains, and called as self pollination.

Table 5.1  Differences between self pollination and cross pollination.

Self Pollination Cross Pollination

Pollen grains are transferred from the anther Pollen grains are transferred from the anther of
to the stigma of the same flower or to another one flower to the stigma of another flower of the
flower of the same plant. same kind or different plant.
Plants do not need to produce pollen grains in a Plants need to produce pollen grains in larger
large quantity for self pollination quantities to increase the chance of pollination.
It does not produce changes in the characteristics Cross pollination does introduce variations in
of new plants. the characteristics of new plants.

Pollination in Plant

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Beans (Fabaceae) and tomatoes 5.2.4 Fertilization

(Solanaceae) commonly self-pollinate. Even During pollination, pollen grains reach
though, for example, tomato self pollinate, stigma. What happens to them after this?
they need the help of the insects to create Substances produced on the stigma causes
vibrations within the flowers that will the pollen grain to germinate. During
effectively loosen the pollen. Paddy is mostly the germination a tube develops from the
self pollinating using just gentle wind as the pollen grain which carries male gametes and
pollinating agent. The agents that are helping ultimately reaches female gamete inside the
in pollination are called pollinators.
ovary through the style. Male gamete fuses
In many plants, pollens have to come with the female gamete to form zygote. This
from some other flowers. This is obvious process is known as fertilization.
in case of plants which have distinct male
Where is this female gamete located?
and female flowers like pumpkin. In some
Inside the ovary, small rounded structures,
flowers the gynoecium matures first before
the androecium shed pollens. Such plants ovules are present. In these ovules, female
need cross pollination. Plants such as apples, gamete is present. To know more about this,
plums, strawberries, pumpkins use insects for we should cut ovary of a flower in longitudinal
cross-pollination. and transverse ways.

Life cycle
of a plant

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Cut a ovary of a flower both vertically and membranous with some granule like, which
horizontally. Observe the ovules. Compare is edible.
the ovary and ovules from few different
• In mango the outer skin and middle pulpy
flowers. Are there one or more ovules? Can
are edible and sweet. The inner most part is
you see any connection between the number
with single seed.
of ovules in the ovary and number of seeds in
each fruit? • In pea the fruit is not fleshy, but forms a
covering pouch for many seeds.

In all the above fruits, ovary, a lower most

swollen part of pistil develops into a fleshy
fruit. Ovules present inside the ovary gets
transformed into a seed.

Hence, now with these observations, we

Ovary shall list the changes taking place in a flower
after fertilization. These are collectively said to
Ovule
be post fertilization changes

Pedicel
™™ Calyx sometimes persist with fruit.
Longitudinal Section Transverse Section ™™ Petals wither / fall off.
of an Ovary of an Ovary
™™ Androecium fall off.
Collect some fruits like tomato, brinjal,
™™ Pistil remain and develops into a fruit.
lady’s finger (vegetable), mango, peas and
custard apple and observe. You can see some ™™ Style and stigma fall off
green part above brinjal and lady’s finger. What ™™ Ovary enlarges to store food materials
are they? and develops into a fruit.
Compare mango, custard apple and peas. ™™ Ovules present inside the ovary develops
All these are single fruits but custard apple into seeds.
has many small parts in it, each with a seed.
Mango has a single seed and pea has many The world’s largest and
seeds. What do you understand from the above heaviest seed is the double
observations? coconut. The seed looks like
• A green part above fruits of brinjal and two coconut fused together. It grows only
lady’s finger are sepals of a flower. In in two islands of the Seychelles. A single
some plants, after fertilization, sepal will seed may be 12 inches long, nearly 3 feet
not fall from fruit and remain or persist in circumference and weighs about 18 kg.
with fruit. Orchids have the smallest seeds in
the plant kingdom. 35 million seeds may
• Custard apple is made up of many fruits,
weight only about 25 gram.
aggregated together. Each fruit part is thin,
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piece of a filament will grow into a new filament

5.3  Asexual reproduction
or individual. Likewise spirogyra produces so
We saw that plants reproduce not only many young ones and this process is known as
from seeds but by other processes as well. fragmentation.
The production of new plants without the
involvement of pollination and fertilization is
known as asexual reproduction. Let us study the
types of asexual reproduction.

5.3.1  Vegetative Propagation

In potato, shoot arise from eyes. Sugar cane
and yam also grow like this. Vegetative parts of
the plants such as root, stem and leaves can
help to produce the plant.
5.3.4  Spore Formation
Scarcity of water, high temperature,
nutrient deficiency in soil etc., are
unfavourable conditions. During these
conditions non-flowering plants like algae,
fungi, moss and ferns produce spores. They
germinate into a new plant when favourable
conditions return.
5.3.2 Budding
When we go to a bakery we see so many
types of cakes and breads. These are very soft
in nature. This is due to the presence of yeast.
Single yeast undergoes asymmetric division. It
produces a small protuberance which gradually
grow and detach from the parent cell. This
process is called budding.
Emerging bud Bud
Nucleus
5.4  Modifications of plant parts
Compare the given plants and discuss with
Vacuole your teacher.
(a) (b) (c) (d)
Parent cell Movement of nucleus

5.3.3 Fragmentation
In a pond we see so many algae. Spirogyra
is a filamentous alga. When it matures, the
filament divides into pieces. Each fragment or Carrot Plant Grass

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pluck it from the ground if you wash them

gently, you will notice small roots dangling
from their surface. All these vegetables are in
fact roots of the plant. Instead of thin slender
roots, they have become a place to store the
Onion Potato
food produced by them. Hence, they are thick
Carefully remove a fresh carrot plant from and swollen. One can notice that the tap root of
the soil and observe it. Look at the part we usually
radish is in the shape of spindle, swollen in the
consume as ‘carrot vegetable’. It is not a unripe
middle and tapering at both ends. Such type of
fruit, but the tap root of the carrot plant. We can
modified roots are called spindle shaped root.
see that the tap root of the carrot is swollen. In the
case of the carrot plant, the tap root has a different
characteristics than the usual plants. Normally,
each plant organ originally evolves to meet certain
needs of the plant. For example, roots evolve
primarily to anchor the plant and also to absorb Radish
water and mineral nutrients from the soil.
At times, like in the case of turnip and beet
Leaves are adapted to optimize root, the tap root can acquire a shape of top, that is
photosynthesis. Stems evolve to reach out to spherical at the base and tapering shortly towards
sunlight and also to conduct water from roots to
the apex. They are called as top shaped root.
leaves. However in certain plant species, specific
parts have evolved further in unusual and
surprising ways to meet certain other specific
needs, In some plants, root, stem, and leaves
change their shape and structure to perform
special functions like storage of food, mechanical
support, protection and other vital functions.
This is known as modification.
What appear as the ‘leaf ’ of a cacti are
Beet Root
actually their stem and what appear as ‘spine’ on
them are actually leaf. Its leaves are modified into In case of carrot, the shape is conical, broad
spines, an adaptation to reduce transpiration. at the apex and tapering gradually towards the
Photosynthesis is performed by the stem part of base and such modified roots are called conical
the plant. In this section let us study about the shaped root.
modification of root, stem and leaves.

5.4.1 Modification of Root

a.  Roots for storage
Look at radish, turnip, beet
root, and carrot. They all grow
under the soil. As soon as you Carrot
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Modification Modification
of Root of Leaf
To perform special functions Leaves have changed themselves
the roots change their size and shape. to adopt to their environment

PLANT
MODIFICATION
Modification
of stem
STORAGE OF FOOD Stem modified for storing the SPINES
e.g. Beet root food materials and for e.g.Opuntia
vegetative propagation.

MECHANICAL SUPPORT TENDRILS

AERIAL MODIFIED
e.g. Banyan tree e.g.Pisum
e.g. Cactus

GASES EXCHANGE SUB-AERIAL MODIFIED PHYLLODE

e.g. Avicennia e.g. Eichhornia e.g. Acacia

SUCKING ROOT UNDERGROUND STEM TRAPS

e.g.Cuscuta e.g. ColoCasia e.g. Nepenthus

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Stilt roots
ACTIVITY 7
In sugar cane and maize, adventitious roots
Aim: To study the modification of root. arise from the nodes in cluster at the base of the
Materials Required: Sample / Charts of stem. These roots are called stilt roots which
radish, carrot, beet root, sweet potato, stilt give additional support.
roots and pneumatophores.
Procedure: Carefully observe the shape of
each specimen.
Observation: Draw the diagram and
observe the morphological differences
between the samples. Stilt roots

b.  Mechanical Support

Look at a banyan tree. It seems to have
many trunk, supporting it. However many of
them are actually roots. As the banyan tree is
large and huge, it needs support so that it does
not tilt and fall down. Many plants require such
additional support. Such plants develop roots Sugar cane
on their aerial parts to provide mechanical
Climbing roots
support. These roots grow downward and act
In betel and black pepper, nodes or
as supportive organs. There are three types of
internodes bear roots which help in climbing.
modified roots for support.

Prop roots
Roots are modified to provide mechanical
support as seen in banyan tree. These roots
grow vertically from horizontal branches of a
tree.

Betel

A root growing from a location

other than the underground,
such as from a stem or leaf is
called as adventitious root
Banyan
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c. Breathing roots or Respiratory roots haustorial roots to penetrate the tissue of the
Avicennia is a tree which grows in host plant and suck nutrients from them. They
mangroves or swamps. They have roots which are usually found in parasitic plants that depend
are seen above the ground for the purpose of on the host plants for nutrients.
gaseous exchange. These roots are erect, peg like
structures with numerous pores through which
air circulates. These roots are called breathing
roots or pneumatophores.

Cuscuta

5.4.2  Modification of stems

Can you guess what is common between
ginger, onion bulb and potatoes. All three
Avicennia
are stems. Some plants have their stems
modified for storing food and for vegetative
Vanda is an epiphytic plant,
propagation. Modified stem may be aerial,
which grows on trees. The
subaerial or underground stems.
velamen tissue present in the
epiphytic root absorbs moisture to perform
a.  Aerial Modifications
photosynthesis.
Phylloclade
In dry climate, conserving water is a
challenge. Water evaporates from the surface.
If the surface area is larger, evaporation would
be more and if the surface area is smaller, the
evaporation will be less. Plants with many
leaves have more surface area. Cactus hence
vanda

Vanda

d. Haustorial roots
Roots may also perform some special
functions. Haustoria or sucking roots, are one
such example. Cuscuta a parasite plant, climb
the trees and other vegetation and use the Cactus
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has a thick stem which does most of the food Sucker

production through photosynthesis and Sucker is a short and weak lateral branch
leaves are reduced to small spines with less that grows diagonally upwards and directly
surface area. gives rise to a new shoot. E.g. Chrysanthemum

b.  Sub – aerial Modifications

Stem of some plants remains sub – aerial
which grow horizontally on the surface of the
soil for the purpose of reproduction. There are
four types.

Runner
The stem which grows laterally on the
surface of the soil, breaks up to produce roots Chrysanthemum
where it touches the ground to give rise to new
Offset
plants. E.g. Centella (Vallarai)
An offset is a short and thick branch that
arises from the axial part of a leaf. It has thick
internodes. It produces a tuft of leaves and
cluster of small roots below. E.g. Eichhornia

Centella
Stolon
Stolon is a slender branch of the stem
that grows upwards to some distance and then
Eichhornia
bends towards the ground. Upon touching the
ground, it gives rise to a new plant. E.g. Wild c. Underground modifications
strawberry
In aerial and sub aerial modifications, stem
has indefinite growth. In underground modified
stem, whole stem is burried under the ground
and it has definite growth. Usually stem grows
above the ground, but there are some stems that
grow under the ground to store food. These
underground stems swell and become thick. There
are four types of underground stems. They are:
1. Rhizome    2. Corm
Wild strawberry 3. Tuber     4. Bulb
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1. Rhizom 4. Bulb

It is an underground thick stem with nodes It is a condensed stem which is disc like
and internodes with scale leaves at the node. It and stores food in the fleshy leaves. The bulb has
grows horizontally and has an irregular shape. two types of leaves.
Rhizome have buds. It gives rise to new stem and
• Fleshy Leaves   • Scaly Leaves
leaves. E.g. Ginger and Turmeric
The upper part of the stem has a terminal
bud and it is covered by many scaly leaves. The
inner fleshy leaves store food as seen in garlic
and onion.

Turmeric
2. Corm
This underground stem is round in shape and
flat at the top and bottom. It is a condensed form of
rhizome and bears one or more buds in the axils of
scale leaves. Daughter plants arise from their buds.
E.g. Colocasia
Onion

ACTIVITY 8

Aim: To study the modification of stem

Materials Required: Specimens of ginger,
potato, onion, mint, bougainvillea, acacia,
Colocasia opuntia and locally available specimens.
3. Tuber Procedure: Observe the external
It is an enlarged, spherical underground stem morphology of each specimen.
that stores food. It has many dormant buds on its
Observation: Draw diagram and bring
surface known as 'eyes'. If we plant a part of tuber
out the differences and their function in
with the bud, it grows into a new plant. E.g. Potato
each type of stem modifications.

5.4.3  Modifications of Leaf

Plants have changed themselves to adapt to
the environment they grow. One of them is the
modification of leaves. Leaves of several plants
get modified into different form based on the
Potato purpose and environment.
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1. Spines 4. Traps
Leaves are reduced to spines, and the stem Plants that grow in nitrogen deficient places
is modified into green succulent part to perform adapt themselves well to get it. In Nepenthes,
photosynthesis. Eg. Opuntia the leaves are modified into a flask like structure,
which is used to attract insects and other tiny
animals. The inner wall of the leaf secretes
digestive enzymes that help to digest the insects
and extract the nitrogen needed for the plant.

Opuntia
2. Tendrils
In climbers, the leaf of plant are modified
into elongated structure to help the plants climb
efficiently.
• Gloriosa superba – Leaf tips are modified
into tendrils.
• Pisum sativum (Pea) –Terminal leaflets are
modified into tendrils.

Nepenthes

Points to Remember

™™ Reproduction is an essential function

of living organisms. In plants there are
two types of reproduction – asexual
Pisum sativum reproduction and sexual reproduction.
3. Phyllode ™™ In flowering plants, flowers are the
In Acacia auriculiformis, petioles expand reproductive organs. They produce
to form leaf like structure. They carry out the fruits and seeds through pollination and
function of leaf (Photosynthesis). fertilization.
™™ The male reproductive organ of a flower is
androecium and the female reproductive
organ of a flower is gynoecium.
™™ Transfer of pollen grains from the anther to
stigma is called pollination. There are two
types of pollination - self pollination and
Acacia cross pollination.

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™™ Agents like wind, water, insects and animals ™™ To perform the special function other
are helpful for pollination and are known as than the normal function, the root, stem
pollinators. and leaf externally modify themselves
™™ After pollination, the fusion of male and female according to the environment. So, they
gametes takes place. It is called fertilization. change their size, shape and colour. These
After fertilization, ovary becomes the fruit are called the modification of root, stem
and ovule becomes the seed. and leaves.

Evaluation

I. Choose the appropriate answer. III. S

 tate true or false. If false, correct the
statement.
1. Vegetative propagation by leaves takes place in
1. A complete flower has four whorls.
a. bryophyllum b. fungi
2. The transfer of pollen to the stigma is known
c. virus d. bacteria
as pollination.
2. Asexual reproduction in yeast is
3. Conical shaped root is carrot.
a. spore formation b. fragmentation
4. Ginger is an underground root.
c. pollination d. budding
5. Leaves of aloe vera are fleshy and store
3. Reproductive part of a plant is
water.
a. root   b. stem   c. leaf   d. flower
IV. Match the following
4. Pollinators are
a. wind  b. water  c. insect  d. All the above Petal Opuntia
Fern Chrysanthemum
5. Climbing roots are seen in
Phylloclade Attracts insect
a. betel b. black pepper
Hooks Spore
c. Both of them d. None of them
Sucker Bignonia

II. Fill in the blanks.

V. Answer very briefly.
1. The male reproductive part of a flower is
1. Write two types of reproduction in plants.
__________.
2. What are the two important parts of a
2. __________ is the basal swollen part of the
flower?
gynoecium.
3. Define – Pollination.
3. After fertilization the ovule becomes
4. What are the agents of pollination?
__________.
5. Give example for Corm and Tuber
4. Breathing roots are seen in _________ plants. 6. What is tendril?
5. Onion and garlic are example for __________. 7. What are thorns?
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VI. Answer briefly. a. Assertion is incorrect, Reasoning is correct.

1. Differentiate bisexual flower from unisexual b. Assertion is incorrect, Reasoning is
flower? incorrect.
2. What is cross pollination? c. Assertion is correct, Reasoning is correct.
3. Write notes on phyllode. d. Assertion is correct, Reasoning is incorrect.

VII. Answer in detail. X. Picture based question.

1. Write a brief account on pollination. i. Label the picture
Partsgiven
of a below.
Flower
2. Explain the underground stems.

VIII. Higher Order Questions.

1. Ginger is considered to be a stem, not a
root. Why?
2. What will happen if pollen grain of rose
gets deposited on stigma of lily flower? Will
pollen germination takes place? Why?

IX. C
onsider the following statements and
choose the correct one. ii. Identify the four plants shown in the following
1. Assertion: Pollination and fertilization in table. Name the different modifications in each
flowers produce fruits and seeds. of them.
 Reason: After fertilization the ovary becomes Name Modification
fruit and ovule becomes seed.
Garlic
2. A
 ssertion: An example for conical root is
Turnip
carrot.
Rose plant
Reason: It is an adventitious
 root
modification. Maize

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ICT CORNER

Reproduction and Modification in Plants

Let’s label the parts of the flower.

PROCEDURE :

Step 1: Use the URL to reach stimulation page. Click ‘Run adobe flash’ to launch the
simulation.

Step 2: Select ‘OK’ button to run the activity.

Step 3: Drag a Stamen into the labelled box. Then click ‘OK’ button.

Step 4: Read the instructions at the top of the screen to do the activity.

Step 5: Click ‘Reset’ to refresh.

Step 1 Step 2 Step 3

Step 4
Reproduction plants URL:
http://www.sciencekids.co.nz/gamesactivities/lifecycles.html

*Pictures are indicative only

*If browser requires, allow Flash Player or Java Script to load the page.

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