LSC S1:Reproduction in Plants

Introduction
Reproduction in Plants ,In this chapter, you will acknowledge that the flower is the organ where sexual reproduction occurs leading to the formation of a new plant and that in the other way, the seed can develop into a new and independent plant.
You will also appreciate that the flower is pollinated and fertilised and the seeds formed are also dispersed from one place to another and if the conditions are suitable, they grow into new plants, The aspect of generating new plants from other plant parts that is vegetative propagation will be highlighted in this chapter 8.1 : Pollination and Agents of Pollination
Have you ever seen bees moving from one flower to another? How is their visit important to the plants? Some animals visit flowers as they search for nectar in the process they pollinate the flowers.
For sexual reproduction to occur the male sex cell must fuse with the female sex cell in the ovary. Perform activity 8.1 , to learn more about pollination.
Activity 8.1: Discussing the meaning of pollination and its types

What you need: notebooks, stylus, slate, and perkins brailler and braille papers.

There are a variety of flowers among flowering plants. These flowers have different structures and mode of pollination. The type of pollination of the flower depends on the nature of the flower.
Agents of Pollination
What are pollinators? Why do they visit only coloured flowers? The pollinators of
flowers are important not only to plants but also human beings.
Flowers have different characteristics that enable them to be pollinated by a specific agent of pollination. A pollinator will only visit a specific type of flower. Do activity 8.2, to discover the various agents of pollination.
Activity 8.2: Identifying various agents of pollination
What you need: notebooks, stylus, slate, and perkins brailler and braille papers

What to do
In a group, study Figure. 8.2 and do the tasks that follow.

1. Identify the type of pollinator shown in each picture of Figure. 8.2.
2. Why do these pollinators visit flowers?
3. What are some of the adaptations of the flowers to be pollinated by the pollinators in Figure. 8.2?
4. Apart from pollinators in Figure. 8.2, name other agents of pollination.
   The flowers of flowering plants have some similar basic features. These basic features are modified according to whether they are wind pollinated or insect pollinated. In Activity 8.3, you will understand some of these differences.
   Activity 8.3: Comparing the structures of wind and animal pollinated flowers
   What you need: Panicum inflorescence and hibiscus flower, notebooks, stylus, slate, and perkins brailler, braille papers, flowers and knife What to do: In a group, discuss and do the tasks below:
5. With reason identify the organ of the plant provided.

2. Using a razor blade cut the specimens longitudinally. serve e features using a hand lens.
   Task:
3. Compare the structures of panicum and hibiscus flowers.
4. Describe the appearance of the panicum inflorescence and hibiscus flower.
5. Describe what would transfer pollen grains from the anther to the stigma of each flower.
6. What is the general arrangement of the floral parts of each flower?
7. Compare your findings with that of the other groups.
   Wind pollinated flowers produce a lot of light pollen grains. Why is this so? The chances of pollen grains of wind pollinated flowers landing on the stigma is less compared to insect pollinated flowers.
   8.2: Fertilisation and its Products
   In activity 8.1, you learnt the meaning of pollination. Have you ever wondered what happens after successful pollination? After pollination, the male sex cell in the pollen grain has to join with a female sex cell in the ovary to produce an embryo made up of a plumule and radicle. Do Activity 8.4, to understand more about fertilisation.

Activity 8.4: Discovering the meaning of fertilisation and process of fertilisation in flowering plants
What you need: marker pen, manila paper, notebooks, slate, stylus, perkins brailler and braille papers
In a group:

1. Find out what is meant by the term fertilisation.
2. Outline the process of fertilisation in flowering plants.
3. Find out the products of fertilisation in flowering plants.
4. Compose a poem about the process of fertilisation.
5. Present your findings in class.
   Flowering plants, the pollen grain contains two male sex cells. Why is this so?
   After pollination the pollen grain germinates and fuses with an ovule in the ovary.
   After fertilisation has taken place the ovule develops into a seed. What does the flower develop into?

8.3: Seeds and Fruits
seeds and fruits are the products which develop after fertilisation. Seeds and fruits are without doubt the most important source of food for people and other animals. In activity 8.5, you will discuss the structural difference of seeds and fruits.

Activity 8.5: Comparing seeds and fruits
What you need: bean seed and maize, notebooks, stylus, slate, and perkins brailler and braille papers
What to do
1. From the group of bean seeds and maize grains provided, select out a few from each category.
2.Soak the selected bean seeds and maize grains in water for 30 minutes.
3.Remove the soaked bean seeds and maize grains from water and note their external appearance.
4.Carefully split open the bean seeds and maize grains.
5. Using a hand lens, observe and identify the cotyledons, plumule and radicle.
Task:
1. Why are bean seeds called seeds while maize grains are called fruits?
2.Describe the internal structures of both specimens in your note book.
3.Write or braille the differences between a been seed and maize.
4.Explain how fruits and seeds are important to you. Write or braille your findings.

8.4: Fruit and Seed Dispersal, Its Agents and Importance to Plant Species and Farming
There are various methods plants use to disperse their seeds and fruits away from the parent plant. Why is this important? Different species of plants have different ways of dispersal. You will learn about these ways in Activity 8.6.
Activity 8.6: Finding out how fruits/seeds are dispersed
What you need: notebooks, stylus, slate, seeds, perkins brailler and braille papers
What to do: In small groups, discuss and complete the cross puzzle on fruit and seed dispersal.

Across

1. Plants disperse fruits and seeds to avoid
2. Disperses by wind
3. Farmer disperses the seeds …….
   on exposure on moisture and humidty
4. The fruits ……
5. Dandelion seeds are carried away by the wind and travel like tiny ……
6. Bears and legumes explode by this method
7. Seeds dispersed by wind are usually tiny …. and dry.
8. Seeds of heavy fruits like apples disperse due to the effect of …..
   Down
9. Phenomenon of carrying seeds to distant areas.
10. Disperses by water.
11. In …. walls of the fruit coil inwards creating a force that throws seeds far away.
    seeds pass out along with the foecal matter.
12. ……
13. Poppy, Tocomo, Moringa and Orchids disperse by …..
14. Plants growing on the banks of rivers disperse by the …… of water.
15. Seeds of this plant are dispersed by birds which consume the fruit.
    Adopted from www.vidyaguide.com
    Task
16. What do you understand by the term fruit/ seed dispersal?
17. Compile a report of your findings. Present your work to the entire class.

Plants have adapted to different ways of dispersal like using water, animals, explosive mechanism and wind. The type of dispersal depend on the nature of the fruit.

Activity 8.7: Finding agents and importance of fruit/seed dispersal to plant species and farming
What you need: Different seeds/fruits, notebooks, stylus, slate, seeds, perkins brailler and braille papers
What to do: In small groups:

Task:
I. Study Figure. 8.3 and answer the questions which follow:

2. Identify the agents of fruit/seed dispersal shown in Figure. 8.3.
3. Whataretheadaptationsoftheeachfruitshown in Figure. 8.3foritsmxieofdispersal?
   Describe what would happen to a given plant species if seeds/fruits dispersal take place over a long period of time.
4. Explain the importance of seed/fruit dispersal to plant species and farming.
5. Compile a report of your findings. Present your work to the entire class.
6. 8.5: Other Parts of a Plant that can Develop into a New Plant of the same Kind
   At home when you want plants to reproduce, most often you plant seed. Apart
   from seeds which other organ of a plant can develop into a new plant? Perform
   activity 8.8 to discover them.
   Activity 8.8: Discovering the different forms of asexual reproduction
   What you need: notebooks, stylus, slate, and perkins brailler, braille papers, plant stems, suckers and root tubers

What to do: Study Figure. 8.4.

1. Identify the forms of reproduction shown in Figure. 8.4.
2. Describe how the plants shown in Figure. 8.4 are propagated.
3. Explain how the plants shown in the pictures in Figure 8.4 develop into new plants.
4. Explain how asexual reproduction is important to the farmers or the society.
   8.6: Vegetative Propagation by Cutting, Grafting and Suckers
   In asexual reproduction an organism reproduces without the involvement Of
   another organism. Both animals and plants can undergo asexual reproduction.
   Some plants can be propagated vegetatively. How?
   Activity 8.9: Discovering how to propagate plants by vegetative means
   What you need: notebooks, slate, stylus, perkins brailler, braille papers, radios and smart phones.
   What to do:
5. Listen to a talk from visiting farmer or agriculturalist about obtaining plants from other plant parts by vegetative reproduction.
6. Individually record the findings during the discussion and compile a report your report should include:

a) How to propagate plants by using cuttings, grafting and suckers. Give
examples in each case.
b)When is it appropriate to propagate plants by vegetative means?
c)Hand in the report to the teacher for further guidance.
Vegetative propagation is economically important.
It allows farmers to grow desired variety of a plant in large numbers and evolving
new variety of plant with desired characteristics.
8.7: Advantages and Disadvantages of Vegetative Propagation
Vegetative propagation methods produce new plants from vegetative parts of the parent plant, such as the roots, stems and leaves. Plants like bananas, sugar cane, potatoes, and yams can be propagated by vegetative propagation. Vegetative propagation has both advantages and disadvantages.

Activity 8.10: Discovering advantages and disadvantages of vegetative
propagation
What you need: notebooks, slate, stylus, perkins brailler, braille papers, radios
and smart phones
What to do:
1.Listen to a simulation or an animation on advantages and disadvantages
of vegetative reproduction.
2.In small groups discuss the advantages and disadvantages of vegetative propagation: Use the following guiding questions:
a)What are the advantages and disadvantages of vegetative propagation.
b)How is vegetative propagation important to a farmer.
c)Describe the role of vegetative reproduction in forest improvement.
d)Compile a report and present to the rest of the class.