Teaching sequence
Lesson objective
In this lesson students identify organelles that can be seen under a light microscope and describe the functions of the different organelles.
Introduction
Ask students if they have heard of the digestive system. Explain that the system needs to be organised into different parts or organs to work effectively. The stomach is just one of the organs in the system. Just like systems, cells need to be organised too.
Core
- Introduce the idea of organelles and the jobs they perform within a cell. Some organelles are easy to see under a microscope while others are more difficult.
- Complete the worksheets Seeing nuclei and Elodea cells.
- Examine the leaves of a plant cell (Elodea) under the microscope. Ask students to draw a single cell labelling the cell wall, nuclei, cell membrane, cytoplasm and chloroplasts. Concentrated salt solution can be added to the slide to distinguish the cell membrane from the cell wall.
- Students complete the worksheet Cells vs cities.
- Students complete the worksheet Help wanted.
Conclusion
Ask students the following questions.
- What shape/s are all the cells you have looked at?
- Do you think plant and animal cells look the same? (Are humans green from chloroplasts?)
Give students the task of finding pictures of different shaped cells.