1. Multicellular Organisms

2. Watch the video...
and answer the questions.

3. Multicellular Organisms
Multicellular organisms are organisms made up of many different cells.

4. Reproduction Relay! How many words related to reproduction
can you remember?

5. Reproduction
Reproduction is the production of new members of a species. If organisms fail to reproduce the species could become extinct. This can happen sexually or asexually.

6. Reproduction To reproduce sexually, sex cells (gametes) are required.
Draw a labelled diagram of a sperm cell and an egg cell in your jotter.

7. Gametes

8. Fertilisation
In order for reproduction to be successful, fertilisation must take place.
Fertilisation occurs when the nucleus of the sperm fuses with the nucleus of an egg cell to produce a zygote.
A zygote is the first cell formed immediately after fertilisation.

9. Reproductive Systems
You have been given diagrams of the male and female reproductive systems.
Label these as much as you can using your knowledge from S1/2.

10. Question time!
Name the two main ways in which reproduction can take place.
Give another name for sex cells.
State one similarity and one difference between an egg cell and a sperm cell.
Describe what happens during fertilisation.
Name the cell which is formed as a result of fertilisation.

11. Reproduction Recap

12. Reproduction Recap

13. Watch the video clip...
What are the main steps in the process of fertilisation?

14. Fertilisation
Using the sheet provided try to complete the diagram by labelling the steps correctly.

15. Internal Fertilisation
Internal fertilisation occurs when the sperm and egg meet inside the female’s body.
It is essential the fertilisation in land animals takes place internally since there is no water outside to carry the sperm to the egg.

16. The Developing Embryo
After fertilisation the zygote begins to move along the oviduct and divide by doubling.
It then implants in the side of the womb.

17. The Developing Embryo
As the embryo develops it relies on the placenta.
Use your knowledge from S1/2 to complete the sheet about the function of the placenta.

18. One thing you have learned today...

19. External Fertilisation
External fertilisation occurs when the sperm and egg meet in the water surrounding the parents.
This occurs commonly in fish.

20. Internal vs External Fertilisation
Use the table provided to compare internal and external fertilisation.

21. Internal vs External Fertilisation
Internal Fertilisation
External Fertilisation
Examples of organisms
Fertilisation takes place inside or outside of the mother’s body
Inside mothers body
Outside the mothers body
Fertilised eggs released in to water or stay inside the mother
Sperm sprayed on to the eggs or sperm placed inside mother
Few or very many eggs produced
Young develop inside or outside mother’s body
Most or some of the eggs get fertilised
Most or few of the offspring (babies) survive
Eggs or offspring (babies) looked after, or not looked after by parents
Parents build a nest or no nest

22. Problem solving skills.

23. The Developing Embryo
Plot a graph to demonstrate the development of the zygote into an embryo.
Time (mins)
Number of Cells 1 30 2 60 4 90 8
120 16
150 32
180 64

24. Problem Solving Stations
Work your way around the stations practicing your problem solving skills.
You have 10 mins at each station.

25. Sexual Reproduction in Plants

26. Watch the video clip...
What are the main structures found in a flower?

27. Task
Your task is to dissect the flower and label the different structures accurately.
Match the structures to their functions using the sheet provided.

28. Asexual Reproduction Does not involve sex cells or fertilisation.
Only involves one parent.
The offspring are genetically identical to the parent

29. Asexual Reproduction - Examples
Bacteria are one example of asexual reproduction

30. Asexual Reproduction - Examples
Tubers (potato), bulbs (garlic) and runner (strawberry) plants are other examples of asexual reproduction

31. Asexual Reproduction - Examples
Starfish and sea anemones are other examples of asexual reproduction

32. Sexual vs Asexual
Sexual
Asexual