1. Natural Sciences Grade 7
Term 1: Life and Living
Sexual Reproduction in Angiosperms
(PPT 3)

2. Topic 3 Sexual Reproduction
Fertilisation
Natural Sciences – Grade 7

3. Fertilisation
Fertilisation occurs when a male sex cell joins with a female sex cell to start the growth of a new individual.
Natural Sciences - Grade 7
Natural Sciences - Grade 7
Natural Sciences - Grade 7

4. Fertilisation Every pollen contains 2 male sex cells.
The ovule contains the female sex cell (egg).
Natural Sciences - Grade 7
Natural Sciences - Grade 7
Natural Sciences - Grade 7

5. Fertilisation Natural Sciences - Grade 7 Natural Sciences - Grade 7

6. Natural Sciences - Grade 7 Natural Sciences - Grade 7
Go through this slide slowly and use the picture to explain the process of fertilisation.
male gametes = male sex cells
Natural Sciences - Grade 7
Natural Sciences - Grade 7
Natural Sciences - Grade 7

7. Fertilisation Natural Sciences - Grade 7 Natural Sciences - Grade 7
Zygote = fertilised egg
Remember to point out that fertilisation is when FUSION takes place, and not before.
Natural Sciences - Grade 7
Natural Sciences - Grade 7
Natural Sciences - Grade 7

8. Fertilisation Natural Sciences - Grade 7 Natural Sciences - Grade 7

9. Fertilisation
The ovule becomes the seed and the tissue around it becomes the seed coat.
The flower then loses its petals, sepals, stamens and the upper part of the pistil.
As the seed develops, the ovary enlarges and becomes a fruit.
Natural Sciences - Grade 7
Natural Sciences - Grade 7
Natural Sciences - Grade 7

10. Fertilisation Natural Sciences - Grade 7 Natural Sciences - Grade 7
The learners do NOT have to know detail of this drawing. It is important enough for them to see how the process begins with pollination, which results in the formation of a seed/seeds. It is a cycle of events.
Natural Sciences - Grade 7
Natural Sciences - Grade 7
Natural Sciences - Grade 7

11. Fruits with seeds The fruit becomes ripe and is ready to eat.
The seeds develop a pip around it, which gets thrown away after the fruit has been eaten.
Some animals eat the fruit and the pip. The seed is excreted in the droppings.
The seed will germinate when conditions are right.
Natural Sciences - Grade 7
Natural Sciences - Grade 7
Natural Sciences - Grade 7

12. Fertilized ovule becomes the seed inside the fruit.
Natural Sciences - Grade 7
Natural Sciences - Grade 7
Natural Sciences - Grade 7