Fertilization and Formation of Fruit. Level (6) Prepared By: Shumaila Saeed.

Fertilization and Formation of Fruit.

Level (6) Prepared By:

Shumaila Saeed.

OBJECTIVES.

  Analyzing.

To make them understand the process of Pollination and its importance, the teacher will give the definition and explanation of pollination with the help of commonly found pollinators (agent) which plays a very important role in the process of Pollination.

Evaluating.

Teacher will assest the students by giving them worksheets, multiple choice questions (mcq’s) diagrams for labeling, short question answers.

Creating.

At the end of the lesson students will be able to draw the diagrams/ charts showing types of pollination

Pollination is the transfer of pollen from the anthers of one flower to the stigma of that or another flower.

Pollination is the first indispensable step in a process that results in the production of fruits, vegetables, nuts and seeds

There are two types of Pollination:

Self Pollination.

Cross Pollination.

Self Pollination.

This type of pollination occurs when the anther and stigma are either in the same flower, or in different flowers on the same plant

Cross Pollination.

Cross pollination occurs when the two flowers involved are from different plants rather then from the same one.

Fertilization.

Fertilization is the fusion (union) of male and female gametes (sex cells)

Sr no.

Self pollination Cross pollination

1. When pollen grains from a flower are carried to the stigma of the same flower or on the other flower of the same plant, the phenomenon is called self pollination

When the pollen grains from a flower are carried to the stigma of the flower on other plant, the phenomenon is called cross pollination.

2. Flowers exhibiting self pollination, sometimes do not need any pollinating agent

Flowers exhibiting cross pollination need some pollinating agents

3. From the genetical as well as quality point of view Self pollination is less preferable

From the genetical as well as quality point of view Cross pollination is better and more preferable than self pollination

Agents of Pollination.

Sr no.

Insect Pollinated Flowers Wind Pollinated Flowers

1. They are large and attractive The flowers are usually small and green

2. The petals are large and brightly coloured  with lines to guide the insects to the nectar

The petals are small or absent  and do not get in the way of pollen

3. There is scent and nectar to attract the insects

There is no scent  or nectar because there is no need to attract insects

Sr no.

Insect Pollinated Flowers Wind Pollinated Flowers

4. The anthers are inside the flower where an insect will attract them

The anthers hang out of the flower and they can be shaken by the wind

5 The pollen grains are larger and sticky, so they will become attached to an insect

There is a lot of very small,  dry pollen grains which  will fly easily in the wind

6 The stigmas are shorter and sticky, so pollen grains attached to an insect will stick to them

The stigmas hang out of the flowers, they are feathery and sticky and can catch pollen

Insect Pollinated Flowers.

Wind Pollinated Flowers.

The wind pollinates many plants. Usually they have less colourful, unscented flowers and do not produce nectar.

The stamens and pistils of these plants are often long.

Their pollen is usually lighter in weight than other plant pollen. The wind carries the pollen from one plant to another.

Without brightly coloured flowers or sweet nectar to attract bees, wheat relies on the

wind for pollination

Wind plays a major role in pollinating crops such as corn.

Water Pollinated Flowers.

Birds Pollinated Flowers.

Some birds, especially hummingbirds, pollinate plants. The plants that attract birds are generally brightly coloured, with red, orange or yellow flowers, but are often odourless, since birds have a poor sense of smell. The flowers are often long and tubular, with lots of nectar, and are sturdy enough for perching on.

As they fly about in search of sweet nectar, hummingbirds pollinate the flowers they visit.

A fruit is defined as the ripened ovary of a flowering plant and contains seeds , which includes, apples, orange, plum,

etc.

Parts of fruits.

A fruit consists of two main parts:

(i) Pericarp. (ii) Seeds.

Pericarp.

The pericarp develops from the ovary wall.

Seeds.

The seeds develop from the ovules, which are attached to the placenta

Functions of fruit.

The two main functions of fruit are as follows:

To protect seed while they germinate.

To help disperse seed away from the parent plant.

Need and Significance of Pollination.

     If plants were not pollinated they wouldn't be able to reproduce and would die

      Pollination leads to fertilization, forming seeds and fruits, which are used as food by us and other animals.

     In crops, we eat the fruit that develops with the seed, for example citrus fruit and tomatoes.

Significance of Fertilization.

The significance of fertilization are as follows..

It rises to formation of a new organism/In case of plants it develops into a fruit.

It is the successful formation of zygote by the fusion of sexgerm cells that are female and male gametes.

It leads to a successful reproduction attempt.

It ultimately leads to a replication of a new organism as an offspring.

QUIZ. MCQ’SQ1.Choose the best answer from the following options.

/051. _________ type of pollination is very wasteful because very little of the pollen reaches the stigma of flower through it.

a. Water b.Wind. c. Insect.2. The most important pollinating insects are the _________ a. ants. b. moths. c. bees. 3. Humming birds have _______ beaks. a. pointed. b. ugly. c. beautiful.4.________ is defined as a ripened ovary of the flowering plants. a. Vegetables. b. Fruit. c. None of above.5. There are _______ parts of fruit. a. two. b. three. c. four.

Q2. Fill in the blanks. /05

___________ Pollination is better than the self pollination.

The transfer of pollen grains from the anther to the stigma of the flower is called __________.

Fruit _________ seeds while they germinate.

When the pollen sacs are ripe ,they _______ open.

Fertilization and Pollination must take place ________fruits and seeds are produced.

THE END.

THANK YOU.